ORCID Profile
0000-0002-1559-330X
Current Organisation
University of Sydney
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Research Topics
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Top 5 Research Topics
ANZSRC Field of Research (FoR)
Materials Engineering | Metals and Alloy Materials | Nanoscale Characterisation | Instruments And Techniques | Materials Engineering Not Elsewhere Classified | Nanotechnology | Composite Materials | Alloy Materials | Condensed Matter Physics | Composite and Hybrid Materials | Functional Materials | Nanotechnology | Nanomaterials | Manufacturing Engineering | Manufacturing Processes and Technologies (excl. Textiles) | Physical Chemistry (Incl. Structural) | Zoology | Materials Engineering not elsewhere classified | Polymers and Plastics | Animal Anatomy And Histology | Optics And Opto-Electronic Physics | Physical Metallurgy | Other Physical Sciences | Physical Sciences Not Elsewhere Classified | Manufacturing Engineering Not Elsewhere Classified | Biomaterials | Condensed Matter Characterisation Technique Development | Structural Chemistry | Optical Physics | Chemical Spectroscopy | Colloid And Surface Chemistry | Physical Chemistry Of Macromolecules | Software Engineering | Communications Technologies | Integrated Circuits | Compound Semiconductors | Electrical Engineering | Ceramics | Bioinorganic Chemistry | Optical And Photonic Systems | Structural Engineering | Computer Communications Networks | Aerospace Materials | Analysis Of Algorithms And Complexity | Interdisciplinary Engineering Not Elsewhere Classified | Process Control And Simulation | Sustainable Agricultural Development | Numerical Modelling and Mechanical Characterisation | Dental Materials and Equipment | Nanofabrication, Growth and Self Assembly | Biological And Medical Chemistry | Ceramics | Computer Software | Polymers | Information Systems | Interorganisational Information Systems | Biological Sciences Not Elsewhere Classified | Information Systems Organisation | Medicinal and Biomolecular Chemistry not elsewhere classified | Data Security | Global Information Systems | Condensed Matter Physics—Other | Biomaterials | Cellular Interactions (incl. Adhesion, Matrix, Cell Wall) | Image Processing | Surfaces and Structural Properties of Condensed Matter | Pharmacology and Pharmaceutical Sciences not elsewhere classified | Electronic and Magnetic Properties of Condensed Matter; Superconductivity | Condensed Matter Imaging
ANZSRC Socio-Economic Objective (SEO)
Structural Metal Products | Physical sciences | Expanding Knowledge in Engineering | Expanding Knowledge in Technology | Chemical sciences | Structural metal products | Expanding Knowledge in the Physical Sciences | Biological sciences | Scientific instrumentation | Other | Treatments (e.g. chemicals, antibiotics) | Information processing services | Metals (composites, coatings, bonding, etc.) | Manufacturing not elsewhere classified | Integrated circuits and devices | Basic Metal Products (incl. Smelting, Rolling, Drawing and Extruding) not elsewhere classified | Scientific Instruments | Telecommunications | Aluminium | Fabricated Metal Products not elsewhere classified | Manufactured products not elsewhere classified | Plastic products (incl. Construction materials) | Other | Diagnostic methods | Machinery and equipment not elsewhere classified | Application tools and system utilities | Air Force | Fabricated metal products not elsewhere classified | Industrial Machinery and Equipment | Ceramics | Ceramics | Technological and organisational innovation | Communication services not elsewhere classified | Polymeric materials (e.g. paints) | Basic Iron and Steel Products | Dental health | Communication equipment not elsewhere classified | Basic Aluminium Products | Iron and steel (e.g. ingots, bars, rods, shapes and sections) | Solar-photoelectric | Neurodegenerative Disorders Related to Ageing | Production of Biofuels (Biomass) | Rehabilitation of degraded farmland | Other | Other | Sheet Metal Products | Prevention—biologicals (e.g. vaccines) | Polymeric Materials (e.g. Paints) | Expanding Knowledge in the Medical and Health Sciences | Sheet metal products | Energy not elsewhere classified | Expanding Knowledge in the Biological Sciences |
Related Links
Publications
An observation of the binder microstructure in WC-(Co+Ru) cemented carbides using transmission Kikuchi diffraction
Publisher: Elsevier BV
Date: 07-2020
A visualization of shear strain in processing by high-pressure torsion
Publisher: Springer Science and Business Media LLC
Date: 02-2010
First-principles investigation of electrical and magnetic properties of ZnO based diluted magnetic semiconductors codoped with H
Publisher: AIP Publishing
Date: 06-2012
DOI: 10.1063/1.4719977
Abstract: Hydrogen (H) behavior in ZnO based diluted magnetic semiconductors (DMSs) was investigated theoretically. It was found that H exhibits erse electronic and structural behavior across a range of different DMSs, depending on the doped transition metal element. For instance in the extensively debated Co doped ZnO system (ZnO:Co), H dopants do not introduce significant carrier concentrations at room temperature thus carrier mediated magnetism is not attainable by H codoping. In this case, magnetism can be manipulated by other mechanisms. In contrast, in the ZnO:V system, H is positively charged for the entire bandgap region, meaning carrier mediated magnetism may be possible.
Introducing transformation twins in titanium alloys: an evolution of α-variants during additive manufacturing
Publisher: Informa UK Limited
Date: 18-12-2020
Properties of TiO2 as photoelectrode for hydrogen generation using solar energy
Publisher: Springer Science and Business Media LLC
Date: 07-2001
DOI: 10.1007/BF02373560
New developments in the characterization of dislocation loops from LACBED patterns
Publisher: Wiley
Date: 09-2006
DOI: 10.1111/J.1365-2818.2006.01631.X
Abstract: The characterization of the Burgers vector of dislocations from large-angle convergent-beam electron diffraction (LACBED) patterns is now a well-established method. The method has already been applied to relatively large and isolated dislocation loops in semiconductors. Nevertheless, some severe experimental difficulties are encountered with small dislocation loops. By using a 2 microm selected-area aperture and a carbon contamination point to mark the loop of interest, we were able to characterize both the plane and the Burgers vector of dislocation loops of a few tens of nanometres in size present in Al-Cu-Mg alloys.
Self-Healing of Fractured GaAs Nanowires
Publisher: American Chemical Society (ACS)
Date: 18-03-2011
DOI: 10.1021/NL104330H
Precipitate characterisation of an advanced high-strength low-alloy (HSLA) steel using atom probe tomography
Publisher: Elsevier BV
Date: 04-2007
Hidden secrets of deformation: Impact-induced compaction within a CV chondrite
Publisher: Elsevier BV
Date: 10-2016
Toward Ubiquitous Environmental Gas Sensors—Capitalizing on the Promise of Graphene
Publisher: American Chemical Society (ACS)
Date: 25-01-2010
DOI: 10.1021/ES902659D
Abstract: Atomically thin sheets of carbon known as "graphene" have captured the imagination of much of the scientific world during the past few years. Although these single sheets of graphite were under our noses for years-within technologies ranging from the humble pencil, which has been around since at least 1565 (Petroski, H. The Pencil: A History of Design and Circumstance Alfred A. Knopf: New York, 1993), to modern nuclear reactors-graphene was merely considered as part of graphite's crystal structure until 2004, when Novoselov, Geim, and colleagues (Science 2004, 306, 666-669) first presented some of the surprising electrical properties of graphene layers they had isolated by mechanically peeling sheets off graphite crystals. Today, graphene's unique electronic structures and properties, bolstered by other intriguing properties discovered in the intervening years, threaten the dominance of carbon nanotubes, a more mature allotrope of carbon, in potential applications from electronics to sensors. In this review, we will consider the promise of graphene for producing small-scale gas sensors for environmental monitoring.
Microstructural evolution, strengthening and thermal stability of an ultrafine-grained Al–Cu–Mg alloy
Publisher: Elsevier BV
Date: 05-2016
Enhanced strength-plasticity combination in an Al–Cu–Mg alloy——atomic scale microstructure regulation and strengthening mechanisms
Publisher: Elsevier BV
Date: 06-2020
On the pitting corrosion of 2205 duplex stainless steel produced by laser powder bed fusion additive manufacturing in the as-built and post-processed conditions
Publisher: Elsevier BV
Date: 12-2021
Elemental diffusion during the droplet epitaxy growth of In(Ga)As/GaAs(001) quantum dots by metal-organic chemical vapor deposition
Publisher: AIP Publishing
Date: 13-01-2014
DOI: 10.1063/1.4859915
Abstract: Droplet epitaxy is an important method to produce epitaxial semiconductor quantum dots (QDs). Droplet epitaxy of III-V QDs comprises group III elemental droplet deposition and the droplet crystallization through the introduction of group V elements. Here, we report that, in the droplet epitaxy of InAs/GaAs(001) QDs using metal-organic chemical vapor deposition, significant elemental diffusion from the substrate to In droplets occurs, resulting in the formation of In(Ga)As crystals, before As flux is provided. The supply of As flux suppresses the further elemental diffusion from the substrate and promotes surface migration, leading to large island formation with a low island density.
Solute clustering in Al–Cu–Mg alloys during the early stages of elevated temperature ageing
Publisher: Elsevier BV
Date: 09-2010
Effects of trace Cu addition on the microstructure and tensile properties of ZK60 alloy
Publisher: Trans Tech Publications, Ltd.
Date: 06-2010
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.654-656.655
Abstract: ZK60 alloy is one of the most important commercial wrought magnesium alloys. However, it suffers from several deficiencies like severe hot crack tendency and relatively low mechanical properties as compared to aluminum alloys. In this discussion, the microstructures of a ZK60-(0, 0.5 Cu, wt.%) alloy at different heat treatment states were examined by various techniques including optical microscopy (OM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The corresponding room temperature tensile properties of the alloys were also tested. The results indicate that trace Cu addition could dramatically improve the casting properties and tensile performance of the ZK60 alloy. In the peak-aged condition, for ex le, the ultimate tensile strength and relative elongation were 261.4 MPa and 17.51% for the current ZK60-0.5Cu alloy, in contrast to 222.9 MPa and 5.97% for the ZK60 alloy, respectively. The improvements could be mainly attributed to the elevated number density and refinement of the dominant strengthening phase β1΄, together with the presence of C15 Laves phase MgZnCu formed in the ZK60-0.5Cu alloy. In addition, no appreciable change in yield strength was observed.
Grain Size Effect on Deformation Twinning and De-Twinning in a Nanocrystalline Ni-Fe Alloy
Publisher: Trans Tech Publications, Ltd.
Date: 12-2011
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.667-669.181
Abstract: The effect of grain size on the deformation twinning and de-twinning in a nanocrystalline Ni-Fe alloy was investigated using transmission electron microscopy. Specimens with different grain sizes were obtained by severely deforming an electrochemically deposited nanocrystalline Ni-20wt.% Fe alloy using high-pressure torsion, which resulted in continuous grain growth from an average grain size of ~ 21 nm in the as-deposited material to ~ 72 nm for the highest strain applied in this study. Results show that deformation de-twinning occurs at very small grain sizes while deformation twinning takes place when the grain size is larger than ~ 45 nm. The mechanism of the observed grain size effect on twinning and de-twinning is briefly discussed.
Atom probe tomography of phosphorus- and boron-doped silicon nanocrystals with various compositions of silicon rich oxide
Publisher: Springer Science and Business Media LLC
Date: 09-2016
DOI: 10.1557/MRC.2016.37
Effect of grain size on the competition between twinning and detwinning in nanocrystalline metals
Publisher: American Physical Society (APS)
Date: 12-2011
The effects of microalloying on the precipitate microstructure at grain boundary regions in an Mg-Zn-based alloy
Publisher: Elsevier BV
Date: 04-2017
Long-Chain Terminal Alcohols through Catalytic CO Hydrogenation
Publisher: American Chemical Society (ACS)
Date: 06-05-2013
DOI: 10.1021/JA402512R
Abstract: We show that long-chain 1-alcohols can be produced with high selectivities using heterogeneous CO hydrogenation catalysis. This breakthrough is achieved through the targeted design of "CoCuMn" nanosized core-shell particles using co-precipitation of metal salts into oxalate precursors and subsequent thermal decomposition. Using stoichiometric CO/H2 feeds, the selectivities to 1-alcohols or combined 1-alcohols/1-alkenes are usually higher than 60% and occasionally up to 95%. The Anderson-Schulz-Flory chain-lengthening probabilities for these products are higher than 0.6, but usually below 0.9 so as to optimize the C8-C14 slate as feedstock for plasticizers, lubricants, or detergents.
Defect chemistry and electrical properties of La1-xSrxCoO3-δ
Publisher: Springer Science and Business Media LLC
Date: 07-2001
DOI: 10.1007/BF02373572
Defect chemistry and electrical properties of La1-xSrxCoO3-δ
Publisher: Springer Science and Business Media LLC
Date: 07-2001
DOI: 10.1007/BF02373571
Defect chemistry and electrical properties of La1−xSrxCoO3−δ IV. Electrical properties
Publisher: Springer Science and Business Media LLC
Date: 07-2001
DOI: 10.1007/BF02373574
Defect chemistry and electrical properties of La1−xSrxCoO3−δ III. Oxygen nonstoichiometry
Publisher: Springer Science and Business Media LLC
Date: 07-2001
DOI: 10.1007/BF02373573
Solution Epitaxy of Halide Perovskite Thin Single Crystals for Stable Transistors
Publisher: American Chemical Society (ACS)
Date: 27-07-2021
Influence of heat treatment on the microstructure, texture and formability of 2024 aluminium alloy
Publisher: Elsevier BV
Date: 08-2012
Microstructural evolution and phase transformation in twinning induced plasticity steel induced by high-pressure torsion
Publisher: Elsevier BV
Date: 05-2016
3D electron backscatter diffraction study of α lath morphology in additively manufactured Ti-6Al-4V
Publisher: Elsevier BV
Date: 11-2020
Influence of field evaporation on Radial Distribution Functions in Atom Probe Tomography
Publisher: Informa UK Limited
Date: 11-04-2009
Magnetoelectric properties of MgB2 superconductor by SiC doping
Publisher: IEEE
Date: 12-2011
An electron tomography algorithm for reconstructing 3D morphology using surface tangents of projected scattering interfaces
Publisher: Elsevier BV
Date: 03-2010
On the role of twinning and stacking faults on the crystal plasticity and grain refinement in magnesium alloys
Publisher: Elsevier BV
Date: 02-2018
Titanate nanotubes and nanorods prepared from rutile powder
Publisher: Wiley
Date: 08-2005
Single crystal forms induced diverse interface structures in TiO2 (B)/anatase dual-phase nanocomposites
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C5CE02411K
Abstract: Two types of TiO 2 (B) single crystal forms (SCF) and the induced TiO 2 (B)/anatase interfaces with different orientation relationships are investigated by TEM. The dominated (001} SCF is confirmed to reveal larger nanotunnels at the interface which suggests an enhanced Li + transport properties.
Electronic and vibrational properties of yttria-stabilised zirconia from first-principles for 10-40 mol% Y2 O3
Publisher: Elsevier BV
Date: 11-2014
In situ analysis of Refractory Metal Nuggets in carbonaceous chondrites
Publisher: Elsevier BV
Date: 11-2017
A new systematic framework for crystallographic analysis of atom probe data
Publisher: Elsevier BV
Date: 07-2015
DOI: 10.1016/J.ULTRAMIC.2015.02.009
Abstract: In this article, after a brief introduction to the principles behind atom probe crystallography, we introduce methods for unambiguously determining the presence of crystal planes within atom probe datasets, as well as their characteristics: location orientation and interplanar spacing. These methods, which we refer to as plane orientation extraction (POE) and local crystallography mapping (LCM) make use of real-space data and allow for systematic analyses. We present here application of POE and LCM to datasets of pure Al, industrial aluminium alloys and doped-silicon. Data was collected both in DC voltage mode and laser-assisted mode (in the latter of which extracting crystallographic information is known to be more difficult due to distortions). The nature of the atomic planes in both datasets was extracted and analysed.
Microstructure and properties of CoCrFeNi-based multi-principal element alloys containing C and Sc
Publisher: Springer Science and Business Media LLC
Date: 05-2022
DOI: 10.1007/S10853-022-07227-3
Abstract: A series of novel CoCrFeNi-based high-entropy alloys containing Sc and C were designed. These HEAs exhibited hardness, fracture toughness and wear resistance comparable or better than a range of selected benchmark systems. Microstructurally, we observed composite microstructures comprising variously a Sc-rich intermetallic phase, a sigma phase and an FCC solid solution phase within which precipitated M 23 C 6 carbides. The Sc-rich intermetallic phase possessed a stoichiometry close to (Co, M) 2 (Sc, M), where M = Ni and Fe. As the carbon content increased, the hardness levels ‘softened’ from 799 VHN (C-free) to 674 VHN (C = 4 at.%), though the fracture toughness was increased ~ 112%. At the same time, the specific wear rate was enhanced from 0.33 × 10 −3 to 0.14 × 10 −3 mm 3 ·(N m) −1 . The effectiveness of these microstructures in balancing high hardness, crack deflection and a relatively low wear rate was attributed to the enhanced stability of the FCC solid phase as the C content was increased. Graphical abstract
Graphene doping to enhance the flux pinning and supercurrent carrying ability of a magnesium diboride superconductor
Publisher: IOP Publishing
Date: 29-06-2010
Stylohyoid Ligament Calcification and Its Association With Dental Diseases
Publisher: Elsevier BV
Date: 02-2023
The effects of intragallery polymerization on the structure of PMMA–clay nanocomposites
Publisher: Elsevier BV
Date: 11-2005
Crystal Facet Effects on Nanomagnetism of Co3O4
Publisher: American Chemical Society (ACS)
Date: 30-04-2018
Abstract: The magnetic performance of nanomaterials depends on size, shape, and surface of the nanocrystals. Here, the exposed crystal planes of Co
Evidence for room temperature ferromagnetism in the In1−xCrxN system
Publisher: Elsevier BV
Date: 06-2006
Observations of decomposition of martensite during heat treatment of steels using atom probe tomography
Publisher: EDP Sciences
Date: 2009
Towards the correlation of fracture toughness in an ex-service power generating rotor
Publisher: Elsevier BV
Date: 02-2000
The future of atom probe tomography
Publisher: Elsevier BV
Date: 04-2012
Predicting solid-state phase transformations during metal additive manufacturing: A case study on electron-beam powder bed fusion of Inconel-738
Publisher: Elsevier BV
Date: 08-2023
The effect of pre-existing defects on the strength and deformation behavior of alpha-Fe nanopillars
Publisher: Elsevier BV
Date: 2013
Chapter 2: Estimation problems and randomised group algorithms
Publisher: Springer London
Date: 26-11-2013
Atom Probe Tomography on Semiconductor Devices
Publisher: Wiley
Date: 06-04-2016
Atom Probe Microscopy of Strengthening Effects in Alloy 718
Publisher: Oxford University Press (OUP)
Date: 04-02-2019
DOI: 10.1017/S1431927618015611
Abstract: Polycrystalline Ni-based superalloys for aerospace and power generation applications are often precipitation hardened to achieve strengthening at elevated temperatures. Here, atom probe microscopy has become an essential tool to study the complex morphology of nanoscale precipitates. This study focuses on Alloy 718, which is hardened by semi-coherent, ordered γ′ (Ni 3 (Al, Ti)) and γ″ (Ni 3 (Nb)) particles. According to previous research, these particles often occur as duplets or triplets with a stacking sequence dependent on prior processing. This creates various interfaces with a strong impact on the mechanical properties, highlighting the importance of quantitative studies which are challenging with electron microscopy. We present atom probe data reconstruction and analysis approaches particularly suited for precipitation hardened superalloys. While voltage atom probe allows for an accurate reconstruction, the acquired data volume is often limited. Laser-assisted atom probe provides statistically significant data, but the loss of crystallographic information requires correlation with voltage-mode datasets. We further describe an advanced iso-surface method where initially arbitrarily chosen concentration thresholds of Al + Ti for γ′ and Nb for γ″ particles are optimized. Recognizing the importance of the precipitate stacking order, the different types of precipitate interfaces are quantified, and these methods may be applicable to other engineering alloys.
Insight into the deformation mechanisms of alpha-Fe at the nanoscale
Publisher: Elsevier BV
Date: 12-2011
Merits of Pr80Ga20 grain boundary diffusion process towards high coercivity‒remanence synergy of Nd‒La‒Ce‒Fe‒B sintered magnet
Publisher: Elsevier BV
Date: 06-2022
Solute clustering and solute nanostructures in an Al–3.5Cu–0.4Mg–0.2Ge alloy
Publisher: Elsevier BV
Date: 06-2013
Development of novel materials through interface engineering
Publisher: Springer Science and Business Media LLC
Date: 07-2001
DOI: 10.1007/BF02373557
Design, synthesis and characterisation of interfaces in engineering materials
Publisher: Springer Science and Business Media LLC
Date: 07-2001
DOI: 10.1007/BF02373559
Hydrogen-Anion-Induced Carrier Recombination in MAPbI3 Perovskite Solar Cells
Publisher: American Chemical Society (ACS)
Date: 28-10-2021
Influence of surface texturing on scratch/mar visibility for polymeric materials: a review
Publisher: Springer Science and Business Media LLC
Date: 23-09-2017
Atom probe tomography of size-controlled phosphorus doped silicon nanocrystals
Publisher: Wiley
Date: 29-11-2017
Ionic Liquid-Assisted Synthesis of Polyaniline/Gold Nanocomposite and Its Biocatalytic Application
Publisher: Springer Science and Business Media LLC
Date: 15-10-2008
DOI: 10.1007/S11671-008-9182-9
Abstract: In this report, a novel chemical synthesis of polyaniline/gold nanocomposite is explored using ionic liquid (IL) 1-Butyl-3-methylimidazolium hexafluorophosphate. The direct chemical synthesis of polyaniline/gold nanocomposite was initiated via the spontaneous oxidation of aniline by AuCl 4 − in IL. A nearly uniform dispersion of polyaniline/Au particles with a diameter of 450 ± 80 nm was produced by this method, which indicates that this method is more suitable for controlling particle dimensions. It was also found that the electrical conductivity of the polyaniline/gold nanocomposite was more than 100 times higher than that of the pure polyaniline nanoparticles. The polyaniline/gold nanocomposite displays superior function in the biocatalytic activation of microperoxidase-11 because of the high surface area of the assembly and the enhanced charge transport properties of the composite material. We also report the possible application of polyaniline/gold nanocomposite as a H 2 O 2 biosensor.
Medium-Mn Martensitic Steel Ductilized by Baking
Publisher: Springer Science and Business Media LLC
Date: 02-07-2019
Identification of the material properties of Al 2024 alloy by means of inverse analysis and indentation tests
Publisher: Elsevier BV
Date: 11-2011
Additively manufactured Haynes-282 monoliths containing thin wall struts of varying thicknesses
Publisher: Elsevier BV
Date: 11-2022
Anelastic Behavior in GaAs Semiconductor Nanowires
Publisher: American Chemical Society (ACS)
Date: 13-06-2013
DOI: 10.1021/NL401175T
Abstract: The mechanical behavior of vertically aligned single-crystal GaAs nanowires grown on GaAs(111)B surface was investigated using in situ deformation transmission electron microscopy. Anelasticity was observed in nanowires with small diameters and the anelastic behavior was affected by the crystalline defects in the nanowires. The underlying mechanism for the observed anelasticity is discussed. The finding opens up the prospect of using nanowire materials for nanoscale d ing applications.
High-resolution TEM study of the Er distribution in Er-doped SiO2 films prepared by laser ablation
Publisher: Elsevier BV
Date: 05-2007
Electrostatic simulations of a local electrode atom probe: The dependence of tomographic reconstruction parameters on specimen and microscope geometry
Publisher: Elsevier BV
Date: 09-2013
DOI: 10.1016/J.ULTRAMIC.2012.12.012
Abstract: We electrostatically model a local electrode atom probe microscope using the commercial software IES LORENTZ 2D v9.0 to investigate factors affecting the reconstruction parameters. We find strong dependences on the specimen geometry and voltage, and moderate dependences on the tip-aperture separation, which confirm that the current approach to atom probe reconstruction overlooks too many factors. Based on our data, which are in excellent agreement with known trends and experimental results, we derive a set of empirical relations which predict the values of the reconstruction parameters. These may be used to advance current reconstruction protocols by enabling the parameters to be adjusted as the specimen geometry changes.
Overcoming challenges in the study of nitrided microalloyed steels using atom probe
Publisher: Elsevier BV
Date: 2012
DOI: 10.1016/J.ULTRAMIC.2011.10.003
Abstract: Nitrided steels are widely used in the engineering field due to their superior hardness and other attractive properties. Atom probe tomography (APT) was employed to study two Nb-microalloyed CASTRIP steels with different N contents. A major challenge of using APT to study this group of materials is the presence of tails after Fe peaks in the mass spectra, which overestimates the composition for alloying elements such as Nb and Cu in the steels. One important factor that contributes to the tails is believed to be delayed field evaporation from Fe²⁺. This artefact of the mass spectrum was observed to be the most severe when voltage pulsing was used. The application of laser pulses with energy ranging from 0.2 to 1.2 nJ successfully reduced the tails and lead to better compositional measurement accuracy. Spatial resolution in the z-direction (along the tip direction) was observed to be less affected by changing laser energy but deteriorates in x-y direction with increasing laser energy. This investigation suggests that pulsed-laser atom probe with ∼0.4 nJ laser energy can be used to study this group of materials with improved mass resolution while still maintaining high spatial resolution.
The effect of dislocation density on the interactions between dislocations and twin boundaries in nanocrystalline materials
Publisher: Elsevier BV
Date: 04-2012
Effect of austenite deformation temperature on Nb clustering and precipitation in microalloyed steel
Publisher: Elsevier BV
Date: 03-2014
Site-specific specimen preparation for atom probe tomography of grain boundaries
Publisher: Elsevier BV
Date: 05-2007
On the nexus between atom probe microscopy and density functional theory simulations
Publisher: Elsevier BV
Date: 12-2018
Germanium-rich “starburst” cores in silica-based optical fibres fabricated by Modified Chemical Vapour Deposition
Publisher: Elsevier BV
Date: 2004
Influence of the wavelength on the spatial resolution of pulsed-laser atom probe
Publisher: AIP Publishing
Date: 11-2011
DOI: 10.1063/1.3657846
Abstract: Modern atom probes typically incorporate an ultrafast pulsed-laser source with wavelength ranging from infrared (IR) to ultraviolet (UV) depending on the specific instrument. In order to estimate the influence of the wavelength on the accuracy of the technique, the achievable in-depth spatial resolution has been measured for atom probe analyses of the same pure W specimen using three different wavelengths and across a range of laser pulse energies. UV illumination is shown to yield superior spatial resolution to both IR and visible (green) wavelengths. We propose that this improvement relates to a faster decay of temperature enabled by light absorption confined to the near apex region.
Phase Transition between Nanostructures of Titanate and Titanium Dioxides via Simple Wet-Chemical Reactions
Publisher: American Chemical Society (ACS)
Date: 15-04-2005
DOI: 10.1021/JA044689+
Abstract: Titanate nanofibers of various sizes and layered structure were prepared from inorganic titanium compounds by hydrothermal reactions. These fibers are different from "refractory" mineral substances because of their dimension, morphology, and significant large ratio of surface to volume, and, surprisingly, they are highly reactive. We found, for the first time, that phase transitions from the titanate nanostructures to TiO(2) polymorphs take place readily in simple wet-chemical processes at temperatures close to ambient temperature. In acidic aqueous dispersions, the fibers transform to anatase and rutile nanoparticles, respectively, but via different mechanisms. The titanate fibers prepared at lower hydrothermal temperatures transform to TiO(2) polymorphs at correspondingly lower temperatures because they are thinner, possess a larger surface area and more defects, and possess a less rigid crystal structure, resulting in lower stability. The transformations are reversible: in this case, the obtained TiO(2) nanocrystals reacted with concentrate NaOH solution, yielding hollow titanate nanotubes. Consequently, there are reversible transformation pathways for transitions between the titanates and the titanium dioxide polymorphs, via wet-chemical reactions at moderate temperatures. The significance of these findings arises because such transitions can be engineered to produce numerous delicate nanostructures under moderate conditions. To demonstrate the commercial application potential of these processes, we also report titanate and TiO(2) nanostructures synthesized directly from rutile minerals and industrial-grade rutiles by a new scheme of hydrometallurgical reactions.
Nanobeam electron diffraction and high resolution imaging analysis of InN films grown on sapphire
Publisher: Wiley
Date: 2007
DOI: 10.1002/JEMT.20398
Abstract: A JEOL JEM-3000F field emission, analytical, high-resolution transmission electron microscope (HRTEM) was used to study InN films grown on sapphire substrates. It was found that, while the InN films maintained the hexagonal (wurtzite) structure, InN nanodomains with a cubic (zincblende) structure were also formed in the films. Nanobeam electron diffraction techniques were applied for identification of the cubic phase. The identification of the cubic InN was confirmed by HRTEM structural imaging. The cubic InN nanodomains are 3-10 nm in diameter, and are orientated in two different orientations with their [110](cubic) and [110](cubic) axes parallel to each other and their (111)(cubic) planes parallel to the (0001)(hex) plane of the hexagonal InN.
Introduction to NANO-MNRF: A modern Australian research facility for microscopy to the nanometer-level
Publisher: Wiley
Date: 2007
DOI: 10.1002/JEMT.20397
Grain size stabilization of mechanically alloyed nanocrystalline Fe-Zr alloys by forming highly dispersed coherent Fe-Zr-O nanoclusters
Publisher: Elsevier BV
Date: 10-2018
Nanocomposites of layered clays and cadmium sulfide: Similarities and differences in formation, structure and properties
Publisher: Elsevier BV
Date: 02-2008
Low-defect graphene–polyamide-6 composites and modeling the filler–matrix interface
Publisher: Wiley
Date: 21-10-2020
DOI: 10.1002/APP.48630
Origins of hardening in aged AlGuMg(Ag) alloys
Publisher: Elsevier BV
Date: 09-1997
Multiple solution-doping in optical fibre fabrication I – Aluminium doping
Publisher: Elsevier BV
Date: 02-2008
A Crystallography-Mediated Reconstruction (CMR) Approach for Atom Probe Tomography: Solution for a Singleton Pole
Publisher: Elsevier BV
Date: 05-2021
Heterogeneous nucleation of β-type precipitates on nanoscale Zr-rich particles in a Mg-6Zn-0.5Cu-0.6Zr alloy
Publisher: Springer Science and Business Media LLC
Date: 08-06-2012
Abstract: Zirconium (Zr) is an important alloying element to Mg-Zn-based alloy system. In this paper, we report the formation of the β-type precipitates on the nanoscale Zr-rich particles in a Mg-6Zn-0.5Cu-0.6Zr alloy during ageing at 180°C. Scanning transmission electron microscopy examinations revealed that the nanoscale Zr-rich [0001] α rods/laths are dominant in the Zr-rich core regions of the as-quenched s le after a solution treatment at 430°C. More significantly, these Zr-rich particles served as favourable sites for heterogeneous nucleation of the Zn-rich β-type phase during subsequent isothermal ageing at 180°C. This research provides a potential route to engineer precipitate microstructure for better strengthening effect in the Zr-containing Mg alloys.
The Emerging Role of Electronic Medical Records in Pharmacogenomics
Publisher: Springer Science and Business Media LLC
Date: 19-01-2011
Networking strategies of the microscopy community for improved utilisation of advanced instruments: (1) The Australian Microscopy and Microanalysis Research Facility (AMMRF)
Publisher: Elsevier BV
Date: 02-2014
Precipitation strengthening in an ultralight magnesium alloy
Publisher: Springer Science and Business Media LLC
Date: 03-2019
DOI: 10.1038/S41467-019-08954-Z
Abstract: Body-centred cubic magnesium-lithium-aluminium-base alloys are the lightest of all the structural alloys, with recently developed alloy compositions showing a unique multi-dimensional property profile. By hitherto unrecognised mechanisms, such alloys also exhibit exceptional immediate strengthening after solution treatment and water quenching, but strength eventually decreases during prolonged low temperature ageing. We show that such phenomena are due to the precipitation of semi-coherent D0 3 -Mg 3 Al nanoparticles during rapid cooling followed by gradual coarsening and subsequent loss of coherency. Physical explanation of these phenomena allowed the creation of an exceptionally low-density alloy that is also structurally stable by controlling the lattice mismatch and volume fraction of the Mg 3 Al nanoparticles. The outcome is one of highest specific-strength engineering alloys ever developed.
Influence of trace Zr on the microstructure and elevated temperature properties of an Al-Si-Cu-Ni-Mg piston alloy
Publisher: IOP Publishing
Date: 22-02-2019
On conventional versus direct ageing of Alloy 718
Publisher: Elsevier BV
Date: 09-2018
Unabridged phase diagram for single-phased FeSex Te1-x thin films
Publisher: Springer Science and Business Media LLC
Date: 02-12-2014
DOI: 10.1038/SREP07273
Cluster hardening in an aged Al-Cu-Mg alloy
Publisher: Elsevier BV
Date: 03-1997
Nanoscale characterization of silica soots and aluminium solution doping in optical fibre fabrication
Publisher: Elsevier BV
Date: 10-2006
The biocompatibility of diamond-like carbon nano films
Publisher: IEEE
Date: 2006
Grain size and reversible beta-to-omega phase transformation in a Ti alloy
Publisher: Elsevier BV
Date: 09-2010
Evolution of solute clustering in Al-Cu-Mg alloys during secondary ageing
Publisher: Elsevier BV
Date: 03-2010
Enhanced solar-driven benzaldehyde oxidation with simultaneous hydrogen production on Pt single-atom catalyst
Publisher: Elsevier BV
Date: 05-2021
Precipitation processes during the early stages of ageing in Al-Cu-Mg alloys
Publisher: Elsevier BV
Date: 03-1996
THE EFFECT OF TRACE ADDITIONS OF SN ON PRECIPITATION IN AL-CU ALLOYS - AN ATOM-PROBE FIELD-ION MICROSCOPY STUDY
Publisher: Springer Science and Business Media LLC
Date: 09-1995
DOI: 10.1007/BF02671236
In situ formation of crystalline flakes in Mg-based metallic glass composites by controlled inoculation
Publisher: Elsevier BV
Date: 12-2011
Sensing sulfur-containing gases using titanium and tin decorated zigzag graphene nanoribbons from first-principles
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C4CP05919K
Abstract: Selective sensing of metal-doped defective zigzag graphene nanoribbons.
Atom probe crystallography
Publisher: Elsevier BV
Date: 09-2012
Quantifying the nucleation effect of correlated matrix grains in sintered Nd-Fe-B permanent magnets
Publisher: Elsevier BV
Date: 03-2020
Defining the Potential of Nanoscale Re-Os Isotope Systematics Using Atom Probe Microscopy
Publisher: Wiley
Date: 07-06-2018
DOI: 10.1111/GGR.12216
Advances in the calibration of atom probe tomographic reconstruction
Publisher: AIP Publishing
Date: 02-2009
DOI: 10.1063/1.3068197
Abstract: Modern wide field-of-view atom probes permit observation of a wide range of crystallographic features that can be used to calibrate the tomographic reconstruction of the analyzed volume. In this study, methodologies to determine values of the geometric parameters involved in the tomographic reconstruction of atom probe data sets are presented and discussed. The influence of the tip to electrode distance and specimen temperature on these parameters is explored. Significantly, their influence is demonstrated to be very limited, indicating a relatively wide regime of experimental parameters space for sound atom probe tomography (APT) experiments. These methods have been used on several specimens and material types, and the results indicate that the reconstruction parameters are specific to each specimen. Finally, it is shown how an accurate calibration of the reconstruction enables improvements to the quality and reliability of the microscopy and microanalysis capabilities of the atom probe.
Atom Probe Microscopy of Self-Assembled Monolayers: Preliminary Results
Publisher: American Chemical Society (ACS)
Date: 18-03-2010
DOI: 10.1021/LA904459K
Abstract: We have achieved three-dimensional imaging of decanethiol self-assembled monolayers (SAMs) on metal surfaces by atom probe tomography (APT). The present Letter provides preliminary results on Ni [001] and Au [111], shows the analytical potential of APT analysis of SAMs, and details developments in specimen preparation and in data-treatment methodologies. Importantly, the investigation of the mass spectra from analysis of the SAMs revealed no combination of sulfur and hydrogen at the interface between the metal substrates and the organic materials, potentially providing insight about the bonding of the thiols on the substrate.
Atom probe specimen fabrication methods using a dual FIB/SEM
Publisher: Elsevier BV
Date: 09-2007
DOI: 10.1016/J.ULTRAMIC.2007.02.024
Abstract: A dual FIB/SEM provides solutions to many challenges in atom probe specimen preparation. When combined with an in situ lift-out capability, the versatility of this tool allows almost any region of interest, in almost any geometry, to be placed at the apex of a specimen tip. Several preparation techniques have been developed in response to specific application requirements for ex le, in cases where materials are not suitable for electropolishing, or where site-specific analysis is required. Two general techniques, with wide-ranging potential applications, are described in detail here. The first is a 'cut-out' technique that provides a relatively quick means of micro-tip specimen preparation from bulk material s les. The second method is a 'lift-out' technique that can be used in an in situ or ex situ mode and does not require the preparation of pre-sharpened mounting points.
High-pressure torsion induced microstructural evolution in a hexagonal close-packed Zr alloy
Publisher: Elsevier BV
Date: 02-2010
Ilmenite FeTiO3 Nanoflowers and Their Pseudocapacitance
Publisher: American Chemical Society (ACS)
Date: 15-08-2011
DOI: 10.1021/JP203345S
Nitriding of a Nb-microalloyed thin strip cast steel at 525°C
Publisher: Trans Tech Publications, Ltd.
Date: 06-2010
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.654-656.106
Abstract: This study investigates the effect of N diffusion on a Nb-microalloyed steel made by twin roll casting at 525o C in a KNO3 salt bath. Nitriding up to 4 h increases the yield strength of the steel by ~50% with only a small drop in ductility, while 6 hours of nitriding causes brittle fracture. The improved mechanical performance after 4 hours of nitriding is thought to be a combined effect of solid solution strengthening of N diffusion and dispersion strengthening from extremely fine Nb-rich precipitates. Coarse features along grain boundaries consistently observed in steel nitrided for 6 hours are considered to be responsible for brittle fracture in s les nitrided for longer.
Yield Strength Enhancement by Carbon Trapping in Ferrite of the Quenching and Partitioning Steel
Publisher: Springer Science and Business Media LLC
Date: 27-11-2017
Precipitation and clustering in the early stages of ageing in Inconel 718
Publisher: Elsevier BV
Date: 11-2010
Experimental Protocols in Field Ion Microscopy
Publisher: Springer New York
Date: 2012
Experimental Protocols in Atom Probe Tomography
Publisher: Springer New York
Date: 2012
Tomographic Reconstruction
Publisher: Springer New York
Date: 2012
Analysis Techniques for Atom Probe Tomography
Publisher: Springer New York
Date: 2012
Field Ion Microscopy
Publisher: Springer New York
Date: 2012
From Field Desorption Microscopy to Atom Probe Tomography
Publisher: Springer New York
Date: 2012
Specimen Preparation
Publisher: Springer New York
Date: 2012
Distribution of boron and phosphorus and roles of co-doping in colloidal silicon nanocrystals
Publisher: Elsevier BV
Date: 10-2019
NUCLEATION AND GROWTH OF THETA' PRECIPITATION IN SN-MODIFIED AL-CU ALLOYS - APFIM/TEM OBSERVATIONS (VOL 87, PG 223, 1995)
Publisher: Elsevier BV
Date: 09-1995
Microscopic origin of highly enhanced supercurrent in 122 pnictide superconductor
Publisher: Elsevier BV
Date: 11-2014
Atom Probe Microscopy and Materials Science
Publisher: Springer New York
Date: 2012
Revealing latent pole and zone line information in atom probe detector maps using crystallographically correlated metrics
Publisher: Elsevier BV
Date: 2023
DOI: 10.1016/J.ULTRAMIC.2022.113640
Abstract: Poles and zone lines observed within atom probe field evaporation images are useful for a range of atom probe crystallography studies, including calibration of the reconstruction and crystallographic characterisation of microstructural features such as grain boundaries. However, this information is not always readily apparent. Techniques for plotting crystallographically correlated metrics contained within atom probe data to enhance pole and zone line contrast across the detector space are developed. This includes consideration of the electric field, molecular ions, lattice structure retained within the reconstruction, specific elemental species, the number of pulses between detection events, and the lateral distance between sequential detection events. These approaches are then applied to experimental atom probe tomography datasets on technically pure Al, nanocrystalline Al, highly doped Si, and additively manufactured Inconel 738, Haynes 282, and Ti-6Al-4V. The results facilitate the extension of atom probe crystallography studies to a broader range of crystalline datasets where crystallographic information is not readily apparent from existing methods, as well as a deeper understanding of field evaporation behaviour during an atom probe experiment.
Precipitation processes in Al-Cu-MS alloys microalloyed with Si
Publisher: Springer Science and Business Media LLC
Date: 11-2000
DOI: 10.1007/BF02830331
On the multiplicity of field evaporation events in atom probe: A new dimension to the analysis of mass spectra
Publisher: Informa UK Limited
Date: 02-2010
Tracking nanostructural evolution in alloys: Large-scale analysis of atom probe tomography data on Blue Gene/L
Publisher: IEEE
Date: 09-2008
DOI: 10.1109/ICPP.2008.73
Endohedral metallofullerenes, M@C60 (M = Ca, Na, Sr): Selective adsorption and sensing of open-shell NOx gases
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C6CP02249A
Abstract: Based on density-functional theory and non-equilibrium Green's function calculations, we demonstrate that endohedral metallofullerenes (EMFs) are reactive to open-shell gases, and therefore have the potential application as selective open-shell gas sensors.
Martensitic transformation in an intergranular corrosion area of austenitic stainless steel during thermal cycling
Publisher: Elsevier BV
Date: 08-2014
Interpretation of the vacancy-ordering controlled growth morphology of Hg5In2Te8 precipitates in Hg3In2Te6 single crystals by TEM observation and crystallographic calculation
Publisher: Elsevier BV
Date: 02-2015
Intergranular precipitation and chemical fluctuations in an additively manufactured 2205 duplex stainless steel
Publisher: Elsevier BV
Date: 10-2022
Evidence of in-situ Cu clustering as a function of laser power during laser powder bed fusion of 17–4 PH stainless steel
Publisher: Elsevier BV
Date: 10-2022
Strain softening in nanocrystalline Ni-Fe alloy induced by large HPT revolutions
Publisher: Elsevier BV
Date: 05-2011
A Novel Thermomechanical Processing on an Experimental Al-Cu-Mg Alloy — Atomic-Scale Microstructure and Strengthening Mechanisms
Publisher: Elsevier BV
Date: 2019
DOI: 10.2139/SSRN.3458121
Effect of Nb microalloying and hot rolling on microstructure and properties of ultrathin cast strip steels produced by the CASTRIP® process
Publisher: Springer Science and Business Media LLC
Date: 15-02-2011
Precipitation processes in an Al-2.5Cu-1.5Mg (wt. %) alloy microalloyed with Ag and Si
Publisher: Elsevier BV
Date: 10-2003
A comparison of the dry sliding wear of single-phase f.c.c. carbon-doped Fe40.4Ni11.3Mn34.8Al7.5Cr6 and CoCrFeMnNi high entropy alloys with 316 stainless steel
Publisher: Elsevier BV
Date: 12-2020
Phase transformation pathways in Ti-6Al-4V manufactured via electron beam powder bed fusion
Publisher: Elsevier BV
Date: 08-2021
Manipulating the size and morphology of aluminum hydrous oxide nanoparticles by soft-chemistry approaches
Publisher: Elsevier BV
Date: 11-2005
On the roles of graphene oxide doping for enhanced supercurrent in MgB2 based superconductors
Publisher: Royal Society of Chemistry (RSC)
Date: 2014
DOI: 10.1039/C4NR00415A
Abstract: Advanced microscopy techniques and computational simulation to reveal the atomic-scale mechanisms for the highest ever recorded enhancement of supercurrent in MgB 2 -based superconductors.
Effect of Austenitising and Deformation Temperatures on Dynamic Recrystallisation in Nb-Ti Microalloyed Steel
Publisher: Trans Tech Publications, Ltd.
Date: 03-2013
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.753.431
Abstract: An investigation into the influence of the reheat temperature and the austenite deformation temperature on Nb precipitation and recrystallisation kinetics was carried out for a steel containing 0.081C–0.021Ti–0.064Nb (wt. %). Thermo-mechanical processing was carried out using a Gleeble 3500 simulator. The austenite grain structure was correlated to the dispersive properties of Nb atom clustering and precipitation. Irrespective of the reheat temperature, deformation to 0.75 strain at 1075 °C produced a fully recrystallised austenitic microstructure. After deformation at 975 °C, only partial recrystallisation was observed in the s les reheated to the higher temperature, whereas s les reheated to the lower temperature were fully recrystallised. The influence of solute drag and particle pinning effects on the recrystallisation rate is discussed.
Effect of solution treatment on precipitation and age-hardening response of an Al–4Mg–1Cu–0.5Si–0.4Ag (wt%) alloy
Publisher: Elsevier BV
Date: 04-2014
Understanding the scratch behaviour of polymeric materials with surface texture
Publisher: Elsevier BV
Date: 05-2018
On the universality of Suzuki segregation in binary Mg alloys from first principles
Publisher: Elsevier BV
Date: 2015
An overview of the effect of Nb in strengthening Castrip® steel
Publisher: Trans Tech Publications, Ltd.
Date: 03-2013
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.753.559
Abstract: Here we review research in which Vickers hardness tests, optical microscopy, electron backscatter diffraction, and atom probe tomography were used to understand the strengthening effects that can be found with Nb in CASTRIP® steels during thermo-mechanical processing and ageing. Nb addition favours the grain refinement of ferrite by inhibiting the austenite recrystallization when hot rolled and provides a strong cluster-hardening effect during ageing.
Characterising the performance of an ultrawide field-of-view 3D atom probe
Publisher: Elsevier BV
Date: 11-2023
Direct observation of nanoscale dynamics of ferroelectric degradation
Publisher: Springer Science and Business Media LLC
Date: 07-04-2021
DOI: 10.1038/S41467-021-22355-1
Abstract: Failure of polarization reversal, i.e., ferroelectric degradation, induced by cyclic electric loadings in ferroelectric materials, has been a long-standing challenge that negatively impacts the application of ferroelectrics in devices where reliability is critical. It is generally believed that space charges or injected charges dominate the ferroelectric degradation. However, the physics behind the phenomenon remains unclear. Here, using in-situ biasing transmission electron microscopy, we discover change of charge distribution in thin ferroelectrics during cyclic electric loadings. Charge accumulation at domain walls is the main reason of the formation of c domains, which are less responsive to the applied electric field. The rapid growth of the frozen c domains leads to the ferroelectric degradation. This finding gives insights into the nature of ferroelectric degradation in nanodevices, and reveals the role of the injected charges in polarization reversal.
3D microstructure analysis of silicon–boron phosphide mixed nanocrystals
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0NR01023E
Abstract: Microstructure study of boron (B) and phosphorus (P) codoped silicon (Si) nanocrystals (NCs), cubic boron phosphide (BP) NCs and their mixed NCs (B x Si y P z NCs).
Characterization of Ni-base superalloys on the atomic scale by atom probe tomography and spherical-aberration corrected analytical electron microscopy techniques
Publisher: Oxford University Press (OUP)
Date: 31-07-2006
DOI: 10.1017/S1431927606065329
Abstract: Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Microstructural and texture evolution of strip cast Nd-Fe-B flake
Publisher: American Chemical Society (ACS)
Date: 10-11-2017
Si-induced precipitation modification and related age-hardening response of an Al–4Mg–1Cu–0.5Si alloy
Publisher: Elsevier BV
Date: 06-2017
On the Formation of Spherical Metastable BCC Single Crystal Spatter Particles during Selective Laser Melting
Publisher: Elsevier BV
Date: 2019
DOI: 10.2139/SSRN.3464657
Atom probe tomography investigation of heterogeneous short-range ordering in the 'komplex' phase state (K-state) of Fe-18Al (at.%)
Publisher: Elsevier BV
Date: 09-2015
High strength ultrafine/nanostructured aluminum produced by back pressure equal channel angular processing
Publisher: AIP Publishing
Date: 16-07-2007
DOI: 10.1063/1.2755923
Abstract: High strength ultrafine/nanograined aluminum materials with ultimate strength up to 740MPa and Vickers microhardness up to 2285MPa were produced using back pressure equal channel angular processing of ultrafine-sized aluminum powder at 400°C. Microstructure analyses revealed that the attained high strength and microhardness were derived from the presence of nanosized aluminum and γ-alumina grains (5–10nm) as well as residual amorphous alumina. The interaction between the severe shear deformation and the preexisting amorphous alumina, concurrent oxidation, and amorphous to γ-alumina transition was considered to be responsible for the formation of such a refined and complex nanostructure.
Manipulation of Nanoscale Domain Switching Using an Electron Beam with Omnidirectional Electric Field Distribution
Publisher: American Physical Society (APS)
Date: 08-07-2016
A three-dimensional Markov field approach for the analysis of atomic clustering in atom probe data
Publisher: Informa UK Limited
Date: 21-04-2010
Microstructure and microchemistry variation during thermal exposure of low alloy steels
Publisher: Elsevier BV
Date: 08-2002
Evolution of microstructure and mechanical properties in 2205 duplex stainless steels during additive manufacturing and heat treatment
Publisher: Elsevier BV
Date: 02-2022
Synthesis and characterization of sodalite–polyimide nanocomposite membranes
Publisher: Elsevier BV
Date: 11-2009
Medium-range order dictates local hardness in bulk metallic glasses
Publisher: Elsevier BV
Date: 04-2021
Effect of niobium clustering and precipitation on strength of an NbTi-microalloyed ferritic steel
Publisher: Elsevier BV
Date: 06-2014
Hardening and microstructural reactions in high-temperature equal-channel angular pressed Mg-Nd-Gd-Zn-Zr alloy
Publisher: Elsevier BV
Date: 07-2010
Indentation and imprint mapping for the identification of material properties in multi-layered systems
Publisher: Elsevier BV
Date: 03-2011
Deformation-induced crystalline-to-amorphous phase transformation in a CrMnFeCoNi high-entropy alloy
Publisher: American Association for the Advancement of Science (AAAS)
Date: 02-04-2021
Abstract: In situ TEM experiments reveal the crystalline-to-amorphous phase transformation in an ultrafine-grained Cantor alloy.
New technique for the quantification of scratch visibility on polymeric textured surfaces
Publisher: Elsevier BV
Date: 08-2017
Ultrahigh transverse rupture strength in tungsten-based nanocomposites with minimal lattice misfit and dual microstructure
Publisher: Elsevier BV
Date: 02-2021
Internal co-precipitation in aged Al–1.7Cu–0.3Mg–0.1Ge (at.%) alloy
Publisher: Elsevier BV
Date: 05-2008
Dynamic reconstruction for atom probe tomography
Publisher: Elsevier BV
Date: 11-2011
DOI: 10.1016/J.ULTRAMIC.2011.08.005
Abstract: Progress in the reconstruction for atom probe tomography has been limited since the first implementation of the protocol proposed by Bas et al. in 1995. This approach and those subsequently developed assume that the geometric parameters used to build the three-dimensional atom map are constant over the course of an analysis. Here, we test this assumption within the analyses of low-alloyed materials. By building upon methods recently proposed to measure the tomographic reconstruction parameters, we demonstrate that this assumption can introduce significant limitations in the accuracy of the analysis. Moreover, we propose a strategy to alleviate this problem through the implementation of a new reconstruction algorithm that dynamically accommodates variations in the tomographic reconstruction parameters.
Atomic-scale observation of parallel development of super elasticity and reversible plasticity in GaAs nanowires
Publisher: AIP Publishing
Date: 13-01-2014
DOI: 10.1063/1.4861846
Abstract: We report the atomic-scale observation of parallel development of super elasticity and reversible dislocation-based plasticity from an early stage of bending deformation until fracture in GaAs nanowires. While this phenomenon is in sharp contrast to the textbook knowledge, it is expected to occur widely in nanostructures. This work indicates that the super recoverable deformation in nanomaterials is not simple elastic or reversible plastic deformation in nature, but the coupling of both.
Enhanced glass forming ability of Fe–Co–Zr–Mo–W–B alloys with Ni addition
Publisher: Elsevier BV
Date: 08-2005
Atom probe trajectory mapping using experimental tip shape measurements
Publisher: Wiley
Date: 04-08-2011
DOI: 10.1111/J.1365-2818.2011.03522.X
Abstract: Atom probe tomography is an accurate analytical and imaging technique which can reconstruct the complex structure and composition of a specimen in three dimensions. Despite providing locally high spatial resolution, atom probe tomography suffers from global distortions due to a complex projection function between the specimen and detector which is different for each experiment and can change during a single run. To aid characterization of this projection function, this work demonstrates a method for the reverse projection of ions from an arbitrary projection surface in 3D space back to an atom probe tomography specimen surface. Experimental data from transmission electron microscopy tilt tomography are combined with point cloud surface reconstruction algorithms and finite element modelling to generate a mapping back to the original tip surface in a physically and experimentally motivated manner. As a case study, aluminium tips are imaged using transmission electron microscopy before and after atom probe tomography, and the specimen profiles used as input in surface reconstruction methods. This reconstruction method is a general procedure that can be used to generate mappings between a selected surface and a known tip shape using numerical solutions to the electrostatic equation, with quantitative solutions to the projection problem readily achievable in tens of minutes on a contemporary workstation.
Bi-objective Build-to-order Supply Chain Problem with Customer Utility
Publisher: International Digital Organization for Scientific Information (IDOSI)
Date: 07-2018
Atom Probe Tomography of Solute Distributions in Mg-Based Alloys
Publisher: Springer Science and Business Media LLC
Date: 19-08-2009
Preparation of site specific atom probe tips using focused ion beam technology
Publisher: Oxford University Press (OUP)
Date: 31-07-2006
DOI: 10.1017/S1431927606062866
Abstract: Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Sintering of binderless TiN and TiCN-based cermet for toughness applications: Processing techniques and mechanical properties: A review
Publisher: Elsevier BV
Date: 12-2019
Introducing a strain-hardening capability to improve the ductility of bulk metallic glasses via severe plastic deformation
Publisher: Elsevier BV
Date: 2012
On the morphology and crystallography of Hg5In2Te8 precipitation in Hg3In2Te6
Publisher: Elsevier BV
Date: 07-2014
LACBED characterization of dislocation loops
Publisher: Informa UK Limited
Date: 11-10-2006
Microstructural evolution of spinodally formed Fe35 Ni15 Mn25 Al25
Publisher: Elsevier BV
Date: 11-2009
Alternating current bias-assisted photoenhanced oxidation of n-GaN in dionized water
Publisher: IEEE
Date: 07-2008
Exploration of atom probe tomography at sub-10K
Publisher: Elsevier BV
Date: 11-2022
DOI: 10.1016/J.ULTRAMIC.2022.113595
Abstract: The operating temperature is a critical parameter in atom probe tomography experiments. It affects the spatial precision, mass resolving power and other key aspects of the field-evaporation process. Current commercially available atom probes operate at a minimum temperature of ∼25 K when measured at the specimen. In this paper, we explore and implement changes to the mechanical design of both the LEAP
Special issue: Microscopy & microanalysis of engineering materials (MMEM2000) - Preface
Publisher: Elsevier BV
Date: 2001
Annealing effects on the structural, magnetic and electrical properties of the nanocrystalline Fe3O4films
Publisher: IOP Publishing
Date: 14-10-2009
Techniques for the Analysis of Clusters and Aggregations within Atom Probe Tomography
Publisher: Oxford University Press (OUP)
Date: 31-07-2006
DOI: 10.1017/S1431927606069030
Abstract: Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2005
Evidence for high-T c
Publisher:
American Physical Society (APS)
Date:
30-11-2009
Publisher: American Physical Society (APS)
Date: 30-11-2009
Contingency table techniques for three dimensional atom probe tomography
Publisher: Wiley
Date: 2007
DOI: 10.1002/JEMT.20412
Abstract: A contingency table analysis procedure is developed and applied to three dimensional atom probe data sets for the investigation of fine-scale solute co-/anti-segregation effects in multicomponent alloys. Potential sources of error and inaccuracy are identified and eliminated from the technique. The conventional P value testing techniques associated with chi(2) are shown to be unsatisfactory and can become ambiguous in cases of large block numbers or high solute concentrations. The coefficient of contingency is demonstrated to be an acceptable and useful basis of comparison for contingency table analyses of differently-conditioned materials. However, care must be taken in choice of block size and to maintain a consistent overall composition between experiments. The coefficient is dependent upon block size and solute composition, and cannot be used to compare analyses with significantly different solute compositions or to assess the extent of clustering without reference to that of the randomly ordered case. It is shown that as clustering evolves into larger precipitates and phases, contingency table analysis becomes inappropriate. Random labeling techniques are introduced to infer further meaning from the coefficient of contingency. We propose the comparison of experimental result, mu(exp), to the randomized value, micro(rand), as a new method by which to interpret the quantity of solute clustering present in a material. It is demonstrated that how this method may be utilized to identify an appropriate size of contingency table analysis blocks into which the data set is partitioned to optimize the significance of the results.
Twinning via the motion of incoherent twin boundaries nucleated at grain boundaries in a nanocrystalline Cu alloy
Publisher: Elsevier BV
Date: 02-2014
Nanoscale pathways for human tooth decay – Central planar defect, organic-rich precipitate and high-angle grain boundary
Publisher: Elsevier BV
Date: 03-2020
DOI: 10.1016/J.BIOMATERIALS.2019.119748
Abstract: Understanding the pathways and mechanisms of human tooth decay is central to the development of both prophylaxes and treatments, but only limited information is presently available about the initiation of caries at the nanoscale. By combining atom probe tomography and high-resolution electron microscopy, we have found three distinct initial sites for human dental enamel dissolution: a) along the central dark line (CDL) within carbonated apatite nanocrystals, b) at organic-rich precipitates and c) along high-angle grain boundaries. 3D maps of the atoms within hydroxyapatite nanocrystallites in sound and naturally-decayed human dental enamel reveal a higher concentration of Mg and Na in the CDL. The CDL is therefore thought to provide a pathway for the exchange of ions during demineralization and remineralization. Mg and Na enrichment of the CDL also suggests that it is associated with the ribbon-like organic-rich precursor in amelogenesis. Organic-rich precipitates and high-angle grain boundaries were also shown to be more vulnerable to corrosion while low-angle grain boundaries remained intact. This is attributed to the lower crystallinity in these regions.
Microscopic bonding mechanism of welding interface with molten Cu-4Zn deposited on solid-state steel
Publisher: Elsevier BV
Date: 05-2008
Cluster strengthening of Nb-microalloyed ultra-thin cast strip steels produced by the CASTRIP® process
Publisher: Elsevier BV
Date: 04-2013
Raman spectroscopy: Alternate method for strain and carbon substitution study in MgB2
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-0012
A Method to Extract Materials Properties from Multilayer Material Systems
Publisher: Trans Tech Publications, Ltd.
Date: 06-2010
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.654-656.2775
Abstract: This article presents an inverse analysis method based on an instrumented indention to extract materials properties from multilayer material systems. In this case, a 12-layers system comprising of two alternate materials is considered. Each layer is 1 μm thick. The material properties selected for the layers are within the range of common commercial aluminium alloys. The yield stress and strain hardening exponent of the two layers were identified based on a power law type equation to define the stress-strain relationship. A 2D axis-symmetric indenter having 70.3 half angle was used, which is representative of a Berkovich or a Vickers indenter. The use of finite element analyses was substituted with a fast and equally accurate approach for the iterative optimization procedure. Thus, the computation time was considerably reduced. The robustness is tested using pseudo-experimental results, in terms of indentation curve and imprint on the material, with added random noises of 2.5%, 5.0%, 7.5% and 10.0%. The proposed approach provides a good estimate of the sought material properties. It is envisaged that this approach can become of assistance in the evaluation of the material properties for multilayer coatings and small devices.
Assessing the Spatial Accuracy of the Reconstruction in Atom Probe Tomography and a New Calibratable Adaptive Reconstruction
Publisher: Oxford University Press (OUP)
Date: 04-2019
DOI: 10.1017/S1431927619000369
Abstract: We define a measure for the accuracy of tomographic reconstruction in atom probe tomography, named here the spatial error index. We demonstrate that this index can be used to compare rigorously the spatial accuracy of various different approaches to the calculation of tomographic reconstruction. This is useful, for ex le, to evaluate the performance of alternate tomographic reconstruction approaches, and ensures that the comparisons are independent of in idual data quality or other instrumental parameters. We then introduce a new “adaptive reconstruction” formalism that uses a progression of reconstruction parameters based on a per-atom correction from the cube root of the inverse of the voltage, along with linear correction factors linked to the evaporation sequence. We apply the measure for spatial accuracy to this new reconstruction protocol.
Role of structural defects on ferromagnetism in amorphous Cr-doped TiO 2 films
Publisher: AIP Publishing
Date: 24-07-2006
DOI: 10.1063/1.2240139
Abstract: Amorphous CrxTi1−xO2 films with different Cr concentrations of 0⩽x⩽0.16 were prepared by cosputtering method at room temperature. All as-deposited s les show hysteresis behavior from 2to340K and the Curie temperatures are well above 390K. The saturation magnetization is about 3.21×10−1μB∕Cr for x=0.05 at 340K and decreases with increasing Cr dopant. After annealing at temperature above 300°C, the films crystallized into anatase structure and lost their ferromagnetic property. The results indicate that the ferromagnetism in amorphous Cr-doped TiO2 films is intrinsic and the structural defects play an important role in the ferromagnetism of Cr:TiO2 system.
Deformation-induced medium-range order changes in bulk metallic glasses
Publisher: American Physical Society (APS)
Date: 25-04-2022
The segregation of transition metals to iron grain boundaries and their effects on cohesion
Publisher: Elsevier BV
Date: 06-2022
On the formation of spherical metastable BCC single crystal spatter particles during laser powder bed fusion
Publisher: Elsevier BV
Date: 03-2020
A Comparison of Statistically Equivalent and Realistic Microstructural Representative Volume Elements for Crystal Plasticity Models
Publisher: Springer Science and Business Media LLC
Date: 28-03-2022
DOI: 10.1007/S40192-022-00257-4
Abstract: Two methods used to construct a microstructural representative volume element (RVE) were evaluated for their accuracy when used in a crystal plasticity-based finite element (CP-FE) model. The RVE-based CP-FE model has been shown to accurately predict the complete tensile stress–strain response of a Ti–6Al–4V alloy manufactured by laser powder bed fusion. Each method utilized a different image-based technique to create a three-dimensional (3D) RVE from electron backscatter diffraction (EBSD) images. The first method, referred to as the realistic RVE (R-RVE), reconstructed a physical 3D microstructure of the alloy from a series of parallel EBSD images obtained using serial-sectioning (or slicing). The second method captures key information from three orthogonal EBSD images to create a statistically equivalent microstructural RVE (SERVE). Based on the R-RVEs and SERVEs, the CP-FE model was then used to predict the complete tensile stress–strain response of the alloy, including the post-necking damage progression. The accuracy of the predicted stress–strain responses using the R-RVEs and SERVEs was assessed, including the effects of each microstructure descriptor. The results show that the R-RVE and the SERVE offer comparable accuracy for the CP-FE purposes of this study.
Strength, grain refinement and solute nanostructures of an Al-Mg-Si alloy (AA6060) processed by high-pressure torsion
Publisher: Elsevier BV
Date: 2014
On the retrieval of crystallographic information from atom probe microscopy data via signal mapping from the detector coordinate space
Publisher: Elsevier BV
Date: 06-2018
DOI: 10.1016/J.ULTRAMIC.2018.02.006
Abstract: Atom probe tomography is a powerful microscopy technique capable of reconstructing the 3D position and chemical identity of millions of atoms within engineering materials, at the atomic level. Crystallographic information contained within the data is particularly valuable for the purposes of reconstruction calibration and grain boundary analysis. Typically, analysing this data is a manual, time-consuming and error prone process. In many cases, the crystallographic signal is so weak that it is difficult to detect at all. In this study, a new automated signal processing methodology is demonstrated. We use the affine properties of the detector coordinate space, or the 'detector stack', as the basis for our calculations. The methodological framework and the visualisation tools are shown to be superior to the standard method of crystallographic pole visualisation directly from field evaporation images and there is no requirement for iterations between a full real-space initial tomographic reconstruction and the detector stack. The mapping approaches are demonstrated for aluminium, tungsten, magnesium and molybdenum. Implications for reconstruction calibration, accuracy of crystallographic measurements, reliability and repeatability are discussed.
A multikinetic approach to apatite fission-track thermal modelling using elemental data: data and model results for a Permian and Devonian sample from northern Yukon
Publisher: Natural Resources Canada/CMSS/Information Management
Date: 2021
DOI: 10.4095/328844
On the understanding of the microscopic origin of the properties of diluted magnetic semiconductors by atom probe tomography
Publisher: Elsevier BV
Date: 04-2009
Microscopic unravelling of nano-carbon doping in MgB2 superconductors fabricated by diffusion method
Publisher: Elsevier BV
Date: 09-2015
Microstructural evolution of Fe-rich particles in an Al-Zn-Mg-Cu alloy during equal-channel angular pressing
Publisher: Elsevier BV
Date: 07-2010
Strain-mediated bandgap engineering of straight and bent semiconductor nanowires
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1CP00457C
Abstract: A simple unit-cell model capable of describing the bandgap evolution of III–V and II–VI semiconductor nanowires under strain is proposed. Three key responses upon strain are found and investigated in both wurtzite and zinc-blende polytypes.
Analysis of dynamic segregation and crystallisation in Mg 65 Cu 25 Y 10 bulk metallic glass using atom probe tomography
Publisher: Elsevier BV
Date: 10-2012
On the microstructure and texture evolution in 17-4 PH stainless steel during laser powder bed fusion: Towards textural design
Publisher: Elsevier BV
Date: 08-2022
Effect of Sn addition in preprecipitation stage in Al-Cu alloys: A correlative transmission electron microscopy and atom probe tomography study
Publisher: Springer Science and Business Media LLC
Date: 21-03-2012
Clustering and precipitation processes in a ferritic titanium-molybdenum microalloyed steel
Publisher: Elsevier BV
Date: 2017
Calibrating the atomic balance by carbon nanoclusters
Publisher: AIP Publishing
Date: 18-01-2010
DOI: 10.1063/1.3284498
Abstract: Carbon atoms are counted at near atomic-level precision using a scanning transmission electron microscope calibrated by carbon nanocluster mass standards. A linear calibration curve governs the working zone from a few carbon atoms up to 34 000 atoms. This linearity enables adequate averaging of the scattering cross sections, imparting the experiment with near atomic-level precision despite the use of a coarse mass reference. An ex le of this approach is provided for layer counting of stacked graphene sheets. Suspended graphene sheets with a size below 100 nm are visualized, providing quantitative measurement in a regime inaccessible to optical and scanning probe methods.
Elemental redistribution in a nanocrystalline Ni-Fe alloy induced by high-pressure torsion
Publisher: Elsevier BV
Date: 09-2011
Five-parameter characterization of intervariant boundaries in additively manufactured Ti-6Al-4V
Publisher: Elsevier BV
Date: 11-2020
NUCLEATION AND GROWTH OF THETA' PRECIPITATION IN SN-MODIFIED AL-CU ALLOYS - APFIM/TEM OBSERVATIONS
Publisher: Elsevier BV
Date: 03-1995
Over-the-Counter Medication Use among Parents in Saudi Arabia
Publisher: MDPI AG
Date: 10-01-2023
Abstract: Introduction: Self-medication is a growing public health concern worldwide. Studies have shown a gap between best practice and the current practice of using over-the-counter (OTC) medications. Despite being a well-recognised problem in Saudi Arabia, few studies have investigated OTC medication use in Saudi Arabia. Therefore, this study aimed to investigate the attitudes and knowledge of parents regarding OTC medication use in the Jeddah region, Saudi Arabia. Method: A cross-sectional study was carried out via an electronic questionnaire sent randomly to parents over four months, from 1 January to 30 April 2022. The participants’ characteristics and categorical variables were represented descriptively by frequency and percentage. A Chi-square test was used to test the relationship between the variables. Results: In total, 211 questionnaires were included in this study. Females represented 54.5% of the participants included in the study. Parents belonging to the 18-to-30-year-old group comprised the highest percentage (37.9%), and most of the parents (72.9%) had received an undergraduate education. Family physicians were the most common source (37.3%) of information about OTC medications, whereas more than half of parents purchased OTC medications from the community pharmacy (58.8%). While almost half of the parents (52.1%) visited a family physician when side effects of OTC medications appeared in their children, only (33.6%) stopped giving their children the OTC medicine. The relationship between the sociodemographic characteristics (including educational level, marital status, and employment status) and OTC drug consumption was significant (p 0.001). Conclusion: Educational c aigns are needed to guide patients about the proper use of OTC medications. Studies on OTC medication use are lacking in Saudi Arabia in terms of its frequency, reasons for use, type of self-medication, and contributing factors.
Precipitation reactions in Al–4.0Cu–0.3Mg (wt.%) alloy
Publisher: Elsevier BV
Date: 05-2008
Effect of laser pulsing on the composition measurement of an Al–Mg–Si–Cu alloy using three-dimensional atom probe
Publisher: Elsevier BV
Date: 04-2009
DOI: 10.1016/J.ULTRAMIC.2008.10.012
Abstract: The effect of laser pulse energy on the composition measurement of an Al-Mg-Si-Cu alloy (AA6111) specimen has been investigated over a base temperature range of 20-80K and a voltage range of 2.5-5kV. Laser pulse energy must be sufficiently higher to achieve pulse-controlled field evaporation, which is at least 0.9nJ with a beam spot size of about 5microm, providing an equivalent voltage pulse fraction, approximately 14% at 80K for the alloy specimen. In contrast to the cluster composition, the measured specimen composition is sensitive to base temperature and laser energy changes. The exchange charge state under the influence of laser pulsing makes the detection of Si better at low base temperature, but detection of Cr and Mn is better at a higher temperature and using higher laser energy. No such effect occurs for detection of Mg and Cu under laser pulsing, although Mg concentration is sensitive to the analysis temperature under voltage pulsing. Mass resolution at full-width half-maximum is sensitive to local taper angle near the apex, but has little effect on composition measurement.
What should the density of amorphous solids be?
Publisher: AIP Publishing
Date: 20-11-2019
DOI: 10.1063/1.5113733
Abstract: A survey of published literature reveals a difference in the density of amorphous and crystalline solids (organic and inorganic) on the order of 10%–15%, whereas for metallic alloys, it is found to be typically less than 5%. Standard geometric models of atomic packing can account for the polymeric and inorganic glasses without requiring changes in interatomic separations (bond lengths). By contrast, the relatively small difference in density between crystalline and glassy metals (and metallic alloys) implies variations in interatomic separations due to merging orbitals giving rise to reduced atomic volumes. To test this hypothesis, quantum density functional theory computations were carried out on ordered and irregular clusters of aluminum. The results point to decreasing interatomic distances with decreasing coordination, from which one can deduce that the geometrical method of random hard sphere packing significantly underestimates the densities of amorphous metallic alloys.
Zeolite crystallization in crosslinked chitosan hydrogels: Crystal size control and chitosan removal
Publisher: Elsevier BV
Date: 12-2008
Detecting and extracting clusters in atom probe data: A simple, automated method using Voronoi cells
Publisher: Elsevier BV
Date: 03-2015
DOI: 10.1016/J.ULTRAMIC.2014.11.015
Abstract: The analysis of the formation of clusters in solid solutions is one of the most common uses of atom probe tomography. Here, we present a method where we use the Voronoi tessellation of the solute atoms and its geometric dual, the Delaunay triangulation to test for spatial/chemical randomness of the solid solution as well as extracting the clusters themselves. We show how the parameters necessary for cluster extraction can be determined automatically, i.e. without user interaction, making it an ideal tool for the screening of datasets and the pre-filtering of structures for other spatial analysis techniques. Since the Voronoi volumes are closely related to atomic concentrations, the parameters resulting from this analysis can also be used for other concentration based methods such as iso-surfaces.
Corrosion of a new class of solid solution Al alloys
Publisher: The Electrochemical Society
Date: 20-03-2009
DOI: 10.1149/1.3091906
Abstract: Aluminum alloys derive their favorable mechanical properties from heterogeneous microstructures. The heterogeneity of these microstructures leads to localized corrosion. Whilst there has been intense research in localized corrosion in the past, a very important question remains unanswered: "How small is too small for microstructural features to behave as unique electrochemical entities or local corrosion hot-spots?" Our prior work has indicated that precipitates on the order of a few nm in size can indeed serve as unique electrochemical entities. In this work, we investigate the corrosion behavior of a new class of Al alloys based on inhomogeneous solid solutions. Through heat treatment, a spectrum of chemical heterogeneities ranging from about a couple of solute atoms to many tens of atoms (atomic clusters) may be formed without local changes in crystal structure. The mechanical properties of these alloys are strongly affected by the atomic scale clustering of solute atoms - whilst in this work we present some results for the corrosion properties (pitting propensity) of such alloys.
In vitro studies of cells grown on the superconductor PrOxFeAs
Publisher: Elsevier BV
Date: 06-2009
DOI: 10.1016/J.MICRON.2008.12.005
Abstract: The recent discovery of arsenic-based high temperature superconductors has reignited interest in the study of superconductor: biological interfaces. However, the new superconductor materials involve the chemistry of arsenic and their toxicity remains unclear [Hand, E., 2008. Nature 452 (24), 922]. In this study the possible adverse effects of this new family of superconductors on cells have been examined. Cell culture studies in conjunction with microscopy and viability assays were employed to examine the influence of arsenic-based superconductor PrO(x)FeAs (x=0.75) material in vitro. Imaging data revealed that cells were well adhered and spread on the surface of the superconductor. Furthermore, cytotoxicity studies showed that cells were unaffected during the time-course of the experiments, providing support for the biocompatibility aspects of PrO(x)FeAs-based superconductor material.
Synthesis of dense, single-crystalline CrO2 nanowire arrays using AAO template-assisted chemical vapor deposition
Publisher: IOP Publishing
Date: 17-02-2011
DOI: 10.1088/0957-4484/22/12/125603
Abstract: High-density, vertically aligned CrO(2) nanowire arrays were obtained via atmospheric-pressure CVD assisted by AAO templates. The CrO(2) nanowire arrays show remarkably enhanced coercivity compared with CrO(2) films or bulk. It was found that the length of the nanowires is greatly influenced by the pore diameter of the AAO template used. The growth mechanism and the pore size dependence of the CrO(2) nanowire arrays are discussed. The present method provides a useful approach for the synthesis of CrO(2) nanowire arrays. Such highly ordered nanowire arrays within an AAO template may have important applications in ultrahigh-density perpendicular magnetic recording devices and the mass production of spintronic nanodevices.
Enhanced age-hardening response of Al–4Mg–1Cu (wt.%) microalloyed with Ag and Si
Publisher: Elsevier BV
Date: 06-2013
Atomic-scale tomography of semiconductor nanowires
Publisher: Elsevier BV
Date: 12-2015
Atomic scale insights into the segregation/partitioning behaviour in as-sintered multi-main-phase Nd-Ce-Fe-B permanent magnets
Publisher: Elsevier BV
Date: 12-2020
Atom Probe Tomography of Encapsulated Hydroxyapatite Nanoparticles
Publisher: Wiley
Date: 13-12-2020
Abstract: Hydroxyapatite nanoparticles (HAP NPs) are important for medicine, bioengineering, catalysis, and water treatment. However, current understanding of the nanoscale phenomena that confer HAP NPs their many useful properties is limited by a lack of information about the distribution of the atoms within the particles. Atom probe tomography (APT) has the spatial resolution and chemical sensitivity for HAP NP characterization, but difficulties in preparing the required needle-shaped s les make the design of these experiments challenging. Herein, two techniques are developed to encapsulate HAP NPs and prepare them into APT tips. By sputter-coating gold or the atomic layer deposition of alumina for encapsulation, partially fluoridated HAP NPs are successfully characterized by voltage- or laser-pulsing APT, respectively. Analyses reveal that significant tradeoffs exist between encapsulant methods/materials for HAP characterization and that selection of a more robust approach will require additional technique development. This work serves as an essential starting point for advancing knowledge about the nanoscale spatiochemistry of HAP NPs.
Self-Assembly and Self-Orientation of Truncated Octahedral Magnetite Nanocrystals
Publisher: Wiley
Date: 18-09-2006
Strengthening from Nb-rich clusters in a Nb-microalloyed steel
Publisher: Elsevier BV
Date: 05-2012
Solute segregation and texture modification in an extruded magnesium alloy containing gadolinium
Publisher: Elsevier BV
Date: 11-2011
Atomistic structure of Cu-containing β″ precipitates in an Al–Mg–Si–Cu alloy
Publisher: Elsevier BV
Date: 03-2014
On the roles of clusters during intragranular nucleation in the absence of static defects
Publisher: Springer Science and Business Media LLC
Date: 06-2002
Novel grain boundary solute architecture in a nanostructured ultra-high strength 7075 aluminium alloy
Publisher: Trans Tech Publications, Ltd.
Date: 04-2009
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.618-619.543
Abstract: In recent years, the pursuit of higher strength metals and alloys has led researchers to nanometer scale grain refinement. New nanocrystalline engineering techniques have successfully increased properties for a wide range of materials. Here we report a nanocrystalline 7075 alloy processed by high-pressure torsion that exhibits ultra-high strength and features a hierarchical solute architecture. The new hierarchy of solute architecture was discovered through high-resolution characterisation using novel techniques we have developed in atom probe tomography. These new techniques – nanotexture and fine scale solute cluster measurements, are the focus of this paper. Our results indicate that nanometer-scale engineering of solid solutions could offer a pathway towards a new generation of super-strong alloys that hold promise for creating entirely new regimes of property-performance space.
Microstructural properties of over-doped GaN-based diluted magnetic semiconductors grown by MOCVD
Publisher: IOP Publishing
Date: 07-2012
In-situ synthesis of Ag nanoparticles by electron beam irradiation
Publisher: Elsevier BV
Date: 12-2015
Effect of cyclic rapid thermal loadings on the microstructural evolution of a CrMnFeCoNi high-entropy alloy manufactured by selective laser melting
Publisher: Elsevier BV
Date: 09-2020
Atomically resolved tomography to directly inform simulations for structure-property relationships
Publisher: Springer Science and Business Media LLC
Date: 19-11-2014
DOI: 10.1038/NCOMMS6501
Abstract: Microscopy encompasses a wide variety of forms and scales. So too does the array of simulation techniques developed that correlate to and build upon microstructural information. Nevertheless, a true nexus between microscopy and atomistic simulations is lacking. Atom probe has emerged as a potential means of achieving this goal. Atom probe generates three-dimensional atomistic images in a format almost identical to many atomistic simulations. However, this data is imperfect, preventing input into computational algorithms to predict material properties. Here we describe a methodology to overcome these limitations, based on a hybrid data format, blending atom probe and predictive Monte Carlo simulations. We create atomically complete and lattice-bound models of material specimens. This hybrid data can then be used as direct input into density functional theory simulations to calculate local energetics and elastic properties. This research demonstrates the role that atom probe combined with theoretical approaches can play in modern materials engineering.
Stress-induced reversible and irreversible ferroelectric domain switching
Publisher: AIP Publishing
Date: 09-04-2018
DOI: 10.1063/1.5020534
Abstract: Ferroelectric materials have been extensively explored for applications in electronic devices because of their ferroelectric/ferroelastic domain switching behaviour under electric bias or mechanical stress. Recent findings on applying mechanical loading to manipulate reversible logical signals in non-volatile ferroelectric memory devices make ferroelectric materials more attractive to scientists and engineers. However, the dynamical microscopic structural behaviour of ferroelectric domains under stress is not well understood, which limits the applications of ferroelectric/ferroelastic switching in memory devices. Here, the kinetics of reversible and irreversible ferroelectric domain switching induced by mechanical stress in relaxor-based ferroelectrics was explored. In-situ transmission electron microscopy investigation revealed that 90° ferroelastic and 180° ferroelectric domain switching can be induced by low and high mechanical stresses. The nucleation and growth of nanoscale domains overwhelm the defect-induced pinning effect on the stable micro-domain walls. This study provides deep insights for exploring the mechanical kinetics for ferroelectric/ferroelastic domains and a clear pathway to overcome the domain pinning effect of defects in ferroelectrics.
Near-Perfect Spin Filtering and Negative Differential Resistance in an Fe(II)S Complex
Publisher: American Chemical Society (ACS)
Date: 04-05-2017
DOI: 10.1021/ACS.JPCLETT.7B00551
Abstract: Density functional theory and nonequilibrium Green's function calculations have been used to explore spin-resolved transport through the high-spin state of an iron(II)sulfur single molecular magnet. Our results show that this molecule exhibits near-perfect spin filtering, where the spin-filtering efficiency is above 99%, as well as significant negative differential resistance centered at a low bias voltage. The rise in the spin-up conductivity up to the bias voltage of 0.4 V is dominated by a conductive lowest unoccupied molecular orbital, and this is accompanied by a slight increase in the magnetic moment of the Fe atom. The subsequent drop in the spin-up conductivity is because the conductive channel moves to the highest occupied molecular orbital, which has a lower conductance contribution. This is accompanied by a drop in the magnetic moment of the Fe atom. These two exceptional properties, and the fact that the onset of negative differential resistance occurs at low bias voltage, suggests the potential of the molecule in nanoelectronic and nanospintronic applications.
Microscale Inhomogeneities in Aluminum Solution-Doping of Silica-Based Optical Fibers
Publisher: Wiley
Date: 2007
Ultrahigh-strength submicron-sized metallic glass wires
Publisher: Elsevier BV
Date: 08-2014
Kinetics of Domain Switching by Mechanical and Electrical Stimulation in Relaxor-Based Ferroelectrics
Publisher: American Physical Society (APS)
Date: 06-12-2017
Determination of Young's Modulus of Ultrathin Nanomaterials
Publisher: American Chemical Society (ACS)
Date: 22-07-2015
DOI: 10.1021/ACS.NANOLETT.5B01603
Abstract: Determination of the elastic modulus of nanostructures with sizes at several nm range is a challenge. In this study, we designed an experiment to measure the elastic modulus of amorphous Al2O3 films with thicknesses varying between 2 and 25 nm. The amorphous Al2O3 was in the form of a shell, wrapped around GaAs nanowires, thereby forming an effective core/shell structure. The GaAs core comprised a single crystal structure with a diameter of 100 nm. Combined in situ compression transmission electron microscopy and finite element analysis were used to evaluate the elastic modulus of the overall core/shell nanowires. A core/shell model was applied to deconvolute the elastic modulus of the Al2O3 shell from the core. The results indicate that the elastic modulus of amorphous Al2O3 increases significantly when the thickness of the layer is smaller than 5 nm. This novel nanoscale material can be attributed to the reconstruction of the bonding at the surface of the material, coupled with the increase of the surface-to-volume ratio with nanoscale dimensions. Moreover, the experimental technique and analysis methods presented in this study may be extended to measure the elastic modulus of other materials with dimensions of just several nanometers.
An atom probe characterisation of grain boundaries in an aluminium alloy processed by equal-channel angular pressing
Publisher: Walter de Gruyter GmbH
Date: 12-2009
DOI: 10.3139/146.110227
Abstract: The segregation of solute elements at the grain boundaries of an Al–Zn–Mg–Cu alloy processed by equal-channel angular pressing was characterised using three-dimensional atom probe tomography. The results show that Mg and Cu segregate strongly to the grain boundaries but Zn shows no clear segregation and even becomes depleted near the boundaries. Trace elements such as Zr, Cr, Si and Mn show no clear segregation at the grain boundaries. An increase in the number of passes leads to a decrease in the grain size but there is no clear effect on the levels of solute segregation at the boundaries. The significant segregation of certain major alloying element at the boundaries of ultrafine-grained alloys implies that the less super-saturation solutes in the matrix will be available for precipitation with a decrease in the average grain size.
Atomic and Molecular Hydrogen Impurities in Hybrid Perovskite Solar Cells
Publisher: American Chemical Society (ACS)
Date: 24-01-2022
Inside Front Cover: Atom Probe Tomography of Encapsulated Hydroxyapatite Nanoparticles (Small Methods 2/2021)
Publisher: Wiley
Date: 02-2021
Breaking the icosahedra in boron carbide
Publisher: Proceedings of the National Academy of Sciences
Date: 06-10-2016
Abstract: The extraordinary hardness of boron compounds is related to their internal structure, which is comprised of 12-atom icosahedra arranged in crystalline lattices. In these hierarchical materials, the icosahedra are easy to image with EM, but in idual atoms are not. Here, we show that laser-assisted atom probe tomography can be used to deduce the atomic structure and relative interatomic bond strengths of atoms in boron carbide. To our surprise, the icosahedra disintegrated during the field evaporation process. Statistical analyses of event multiplicity and stoichiometry in the atom probe dataset substantiate that the icosahedra are less tightly bound than their interconnecting chains. Comparisons with quantum mechanics simulations further suggest that this instability plays a role in the amorphization of boron carbide.
Strength, fracture toughness and microstructure of a selection of all-ceramic materials. Part II. Zirconia-based dental ceramics
Publisher: Elsevier BV
Date: 06-2004
Strength, fracture toughness and microstructure of a selection of all-ceramic materials. Part I. Pressable and alumina glass-infiltrated ceramics
Publisher: Elsevier BV
Date: 06-2004
Atomic-scale investigation of interface-facilitated deformation twinning in severely deformed Ag-Cu nanolamellar composites
Publisher: AIP Publishing
Date: 06-07-2015
DOI: 10.1063/1.4926370
Abstract: We report an atomic-scale investigation of interface-facilitated deformation twinning behaviour in Ag-Cu nanolamellar composites. Profuse twinning activities in Ag supply partial dislocations to directly transmit across the Ag-Cu lamellar interface that promotes deformation twinning in the neighbouring Cu lamellae although the interface is severely deformed. The trans-interface twin bands change the local structure at the interface. Our analysis suggests that the orientation relationship and interfacial structure between neighbouring Ag-Cu lamellae play a crucial role in such special interface-facilitated twinning behaviour.
Nanostructural hierarchy increases the strength of aluminium alloys
Publisher: Springer Science and Business Media LLC
Date: 07-09-2010
DOI: 10.1038/NCOMMS1062
Spatial Resolution in Atom Probe Tomography
Publisher: Oxford University Press (OUP)
Date: 18-01-2010
DOI: 10.1017/S1431927609991267
Abstract: This article addresses gaps in definitions and a lack of standard measurement techniques to assess the spatial resolution in atom probe tomography. This resolution is known to be anisotropic, being better in-depth than laterally. Generally the presence of atomic planes in the tomographic reconstruction is considered as being a sufficient proof of the quality of the spatial resolution of the instrument. Based on advanced spatial distribution maps, an analysis methodology that interrogates the local neighborhood of the atoms within the tomographic reconstruction, it is shown how both the in-depth and the lateral resolution can be quantified. The influences of the crystallography and the temperature are investigated, and models are proposed to explain the observed results. We demonstrate that the absolute value of resolution is specimen specific.
Trapped-Hydrogen-Induced Energy Loss in Tin-Based Hybrid Perovskite Solar Cells
Publisher: American Physical Society (APS)
Date: 29-09-2022
Chemistry of grain boundary environments in nanocrystalline Al 7075
Publisher: Elsevier BV
Date: 04-2010
The role of stacking faults and twin boundaries in grain refinement of a Cu-Zn alloy processed by high-pressure torsion
Publisher: Elsevier BV
Date: 07-2010
Conductive polyolefin-rubber nanocomposites with carbon nanotubes
Publisher: Elsevier BV
Date: 2016
Enhanced oscillatory rectification and negative differential resistance in pentamantane diamondoid-cumulene systems
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C5NR07467C
Abstract: We propose a new functionality for diamondoids in nanoelectronics. Based on the nonequilibrium Green's function formalism and density functional theory, we reveal that when attached to gold electrodes, the pentamantane-cumulene molecular junction exhibits large and oscillatory rectification and negative differential resistance (NDR) - depending on the number of carbon atoms in cumulene (Cn). When n is odd rectification is greatly enhanced where the rectification ratio can reach ∼180 and a large negative differential resistance peak current of ∼3 μA. This oscillatory behavior is well rationalised in terms of the occupancy of the carbon 2p states in Cn. Interestingly, different layers of C atoms in the pentamantane molecule have different contributions to transmission. The first and third layers of C atoms in pentamantane have a slight contribution to rectification, and the fifth and sixth layers have a stronger contribution to both rectification and NDR. Thus, our results suggest potential avenues for controlling their functions by chemically manipulating various parts of the diamondoid molecule, thus extending the applications of diamondoids in nanoscale integrated circuits.
High mobility in α-phosphorene isostructures with low deformation potential
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/C9CP05828A
Abstract: The exceptionally low deformation potential is proposed as the key determinant for the high carrier mobility in ten possible α-phosphorene isostructures.
Light output improvement of oxide-textured InGaN-based light-emitting diodes by bias-assisted photoelectrochemical oxidation with imprint technique
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-2009
Electron microscopy and microanalysis of a YBa2Cu3Ox superconducting oxide
Publisher: AIP Publishing
Date: 17-08-1987
DOI: 10.1063/1.98390
Abstract: The onset of superconductivity at 140 K has been observed in the high Tc Y-Ba-Cu-O system in s les consisting of 90% by volume of a single-phase oxide of average cation ratio Y:Ba:Cu≂1:2:3. A sharp superconducting transition in the resistivity has been measured, where Tc0=140 K, Tc=93.2 K, ΔTc=0.5 K, and ‘‘zero resistance’’ was observed at 92.0 K. Transmission electron microscopy and energy dispersive spectroscopy measurements revealed that the superconducting phase consisted of a large number of microcrystallites of ≂0.5 μm size and that these contained a very high defect microtwinned/faulted structure.
An understanding of hydrogen embrittlement in nickel grain boundaries from first principles
Publisher: Elsevier BV
Date: 12-2021
Finite element simulation of scratch on polypropylene panels
Publisher: Elsevier BV
Date: 02-2018
Super Deformability and Young's Modulus of GaAs Nanowires
Publisher: Wiley
Date: 15-02-2011
Multi-holed clay nanotubes and their modification with a polyaniline nanolayer
Publisher: Springer Science and Business Media LLC
Date: 21-09-2011
Segregation of the major alloying elements to Al3(Sc,Zr) precipitates in an Al–Zn–Mg–Cu–Sc–Zr alloy
Publisher: Elsevier BV
Date: 11-2019
Point-by-point compositional analysis for atom probe tomography
Publisher: Elsevier BV
Date: 2014
Giant tuning of ferroelectricity in single crystals by thickness engineering
Publisher: American Association for the Advancement of Science (AAAS)
Date: 16-10-2020
Abstract: Ferroelectricity is engineered by dimension in nanoscale single-crystal ferroelectrics.
Strain-Engineered Ultrahigh Mobility in Phosphorene for Terahertz Transistors
Publisher: Wiley
Date: 08-01-2019
Quantitative binomial distribution analyses of nanoscale like-solute atom clustering and segregation in atom probe tomography data
Publisher: Wiley
Date: 07-2008
DOI: 10.1002/JEMT.20582
Abstract: The applicability of the binomial frequency distribution is outlined for the analysis of the evolution nanoscale atomic clustering of dilute solute in an alloy subject to thermal ageing in 3D atom probe data. The conventional chi(2) statistics and significance testing are demonstrated to be inappropriate for comparison of quantity of solute segregation present in two or more different sized system. Pearson coefficient, mu, is shown to normalize chi(2) with respect to s le size over an order of magnitude. A simple computer simulation is implemented to investigate the binomial analysis and infer meaning in the measured value of mu over a series of systems at different solute concentrations and degree of clustering. The simulations replicate the form of experimental data and demonstrate the effect of detector efficiency to significantly underestimate the measured segregation. The binomial analysis is applied to experimental atom probe data sets and complementary simulations are used to interpret the results.
Mechanical properties of ultrathin gold nanowires from first principles: Interdependencies between size, morphology, and twin boundaries
Publisher: American Physical Society (APS)
Date: 25-08-2020
Mechanical characterisation of material properties using instrumented indentation experiments
Publisher: Trans Tech Publications, Ltd.
Date: 04-2009
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.618-619.215
Abstract: The proposed work makes use of an inverse analysis approach to identify the mechanical properties of a material s le which can be described by means of the elastic modulus, yield stress and strain-hardening parameter. The particularity of the proposed work is the exploitation of the indentation curve as well as the imprint left by the indenter at the end of the test as input information to the inverse analysis. The numerical simulations required by the analysis are carried out by means of the finite element software Abaqus. This paper describes initial work carried out to validate the robustness of the inverse procedure for stainless steel s les using computer-generated data.
Growth and valence excitations of ZnO:M(Al, In, Sn) hierarchical nanostructures
Publisher: American Chemical Society (ACS)
Date: 05-10-2010
DOI: 10.1021/JP103594M
Quantification of graphene based core/shell quantum dots from first principles
Publisher: AIP Publishing
Date: 31-10-2011
DOI: 10.1063/1.3657488
Abstract: Density functional calculations are performed to study the electronic structure of recently proposed graphene/graphane based core/shell quantum dots, which have a type I band alignment and exhibit quantized carrier energy levels. Strong confinement is robust with shell thickness. The bandgap, band offset, and the number of confined carrier orbitals with different size and geometry are determined. Our findings indicate that these core/shell dots are potentially well suited for the design of advanced diode lasers and room-temperature single electron devices. The proposed method to determine the number of confined orbitals is applicable for other quantum dot systems.
The rise of computational techniques in atom probe microscopy
Publisher: Elsevier BV
Date: 10-2013
Effects of crystallization and dopant concentration on the emission behavior of TiO2:Eu nanophosphors
Publisher: Springer Science and Business Media LLC
Date: 03-01-2012
Atom probe crystallography: Atomic-scale 3-D orientation mapping
Publisher: Elsevier BV
Date: 06-2012
Microstructure and mechanical properties of Mg-6Zn-xCu-0.6Zr (wt.%) alloys
Publisher: Elsevier BV
Date: 02-2011
Atom probe microscopy investigation of Mg site occupancy within delta ' precipitates in an Al-Mg-Li alloy
Publisher: Elsevier BV
Date: 06-2012
Graphene based dots and antidots: A comparative study from first principles
Publisher: American Scientific Publishers
Date: 02-2013
Abstract: Graphene based quantum dots and antidots are two nanostructures of primary importance for their fundamental physics and technological applications, particularly in the emerging field of graphene-based nanoelectronics and nanospintronics. Herein, based on first principles density functional theory calculations, we report a comparative study on the electronic structure of these two structurally complementary entities, where the bandgap opening, edge magnetism and the role of hydrogenation are investigated. Our results show the ersity of electronic structures of various dots and antidots, whose properties are sensitive to the edge detailed geometry (including size and shape and edge type). Hydrogen passivation plays an essential roal in affecting the related properties, in particular, it leads to larger bandgap values and suppress the edge magnetism. The frontier orbital analysis is employed to rationalize and compare the complicated nature of dots and antidots. Based on the specific geometrical consideration and the total energy competition of the ground antiferromagnetic and the ferromagnetic states, some magnetic structures (the unpassivated 42-atom-antidot and 54-atom-dot) are proposed to be useful as magnetic switches.
Cork–PLA composite filaments for fused deposition modelling
Publisher: Elsevier BV
Date: 11-2018
A nexus between 3D atomistic data hybrids derived from atom probe microscopy and computational materials science: A new analysis of solute clustering in Al-alloys
Publisher: Elsevier BV
Date: 04-2017
Effects of thermal annealing on the distribution of boron and phosphorus in p-i-n structured silicon nanocrystals embedded in silicon dioxide
Publisher: IOP Publishing
Date: 26-11-2021
Abstract: Thermal annealing temperature and time dictate the microstructure of semiconductor materials such as silicon nanocrystals (Si NCs). Herein, atom probe tomography (APT) and density functional theory (DFT) calculations are used to understand the thermal annealing temperature effects on Si NCs grown in a SiO 2 matrix and the distribution behaviour of boron (B) and phosphorus (P) dopant atoms. The APT results demonstrate that raising the annealing temperature promotes growth and increased P concentration of the Si NCs. The data also shows that the thermal annealing does not promote the incorporation of B atoms into Si NCs. Instead, B atoms tend to locate at the interface between the Si NCs and SiO 2 matrix. The DFT calculations support the APT data and reveal that oxygen vacancies regulate Si NC growth and dopant distribution. This study provides the detailed microstructure of p-type, intrinsic, and n-type Si NCs with changing annealing temperature and highlights how B and P dopants preferentially locate with respect to the Si NCs embedded in the SiO 2 matrix with the aid of oxygen vacancies. These findings will be useful towards future optoelectronic applications.
Ageing behaviour of an Fe–20Ni–1.8Mn–1.6Ti–0.59Al (wt%) maraging alloy: clustering, precipitation and hardening
Publisher: Elsevier BV
Date: 11-2004
Effect of scanning strategy on variant selection in additively manufactured Ti-6Al-4V
Publisher: Elsevier BV
Date: 12-2020
Macroscopic electrical field distribution and field-induced surface stresses of needle-shaped field emitters
Publisher: Elsevier BV
Date: 05-2011
DOI: 10.1016/J.ULTRAMIC.2011.01.024
Abstract: One major concern since the development of the field ion microscope is the mechanical strength of the specimens. The macroscopic shape of the imaging tip greatly influences field-induced stresses and there is merit in further study of this phenomenon from a classical perspective. Understanding the geometrical, as opposed to localized electronic, factors that affect the stress might improve the quality and success rate of atom probe experiments. This study uses macroscopic electrostatic principles and finite element modelling to investigate field-induced stresses in relation to the shape of the tip. Three two-dimensional idealized models are considered, namely hyperbolic, parabolic and sphere-on-orthogonal-cone the shapes of which are compared to experimental tips prepared by electro-polishing. Three dimensional morphologies of both a nano-porous and single-crystal aluminium tip are measured using electron tomography to quantitatively test the assumption of cylindrical symmetry for electro-polished tips. The porous tip was prepared and studied to demonstrate a fragile specimen for which such finite element studies could determine potential mechanical failure, prior to any exhaustive atom probe investigation.
Correlative study of lattice imperfections in long-range ordered, nano-scale domains in a Fe-Co-Mo alloy
Publisher: Elsevier BV
Date: 09-2019
DOI: 10.1016/J.ULTRAMIC.2019.05.005
Abstract: Recent advancements in data mining methods in atom probe microscopy have enabled new quantitative chemical and microstructural characterization beyond the standard three-dimensional reconstruction. For ex le, spatial distribution maps have been developed to enable visualisation of the local lattice occupation of a selected region of interest. However, the precision of such studies yet remains unknown as correlation with complementary methods would be required. Therefore, a correlative study of atom probe microscopy, neutron diffraction and microstructural modelling of long-range ordered, nano-scale domains in a well-researched Fe-Co-Mo Maraging-type steel is presented here. Its microstructure consists of Mo-enriched µ-phase (Fe,Co)
Effect of a High Density of Stacking Faults on the Young's Modulus of GaAs Nanowires
Publisher: American Chemical Society (ACS)
Date: 22-02-2016
DOI: 10.1021/ACS.NANOLETT.5B05095
Abstract: Stacking faults (SFs) are commonly observed crystalline defects in III-V semiconductor nanowires (NWs) that affect a variety of physical properties. Understanding the effect of SFs on NW mechanical properties is critical to NW applications in nanodevices. In this study, the Young's moduli of GaAs NWs with two distinct structures, defect-free single crystalline wurtzite (WZ) and highly defective wurtzite containing a high density of SFs (WZ-SF), are investigated using combined in situ compression transmission electron microscopy and finite element analysis. The Young's moduli of both WZ and WZ-SF GaAs NWs were found to increase with decreasing diameter due to the increasing volume fraction of the native oxide shell. The presence of a high density of SFs was further found to increase the Young's modulus by 13%. This stiffening effect of SFs is attributed to the change in the interatomic bonding configuration at the SFs.
Observation of precipitation evolution in Fe-Ni-Mn-Ti-Al maraging steel by atom probe tomography
Publisher: Springer Science and Business Media LLC
Date: 23-09-2009
Atom probe specimen fabrication methods using a dual FIB/SEM
Publisher: IEEE
Date: 07-2006
Role of point defects in room-temperature ferromagnetism of Cr-doped ZnO
Publisher: AIP Publishing
Date: 13-08-2007
DOI: 10.1063/1.2772176
Assessing environmental impact of textile supply chain using life cycle assessment methodology
Publisher: Informa UK Limited
Date: 11-02-2018
Methodology exploration of specimen preparation for atom probe tomography from nanowires
Publisher: Elsevier BV
Date: 12-2015
DOI: 10.1016/J.ULTRAMIC.2015.06.003
Abstract: Semiconductor nanowires have been intensively explored for applications in electronics, photonics, energy conversion and storage. A fundamental and quantitative understanding of growth-structure-property relationships is central to applications where nanowires exhibit clear advantages. Atom Probe Tomography (APT) is able to provide 3 dimensional quantitative elemental distributions at atomic-resolution and is therefore unique in understanding the growth-structure-property relationships. However, the specimen preparation with nanowires is extremely challenging. In this paper, two ion beam free specimen preparation methods for APT are presented which are efficient for various nanowires.
Evaluation of carbon incorporation and strain of doped MgB2 superconductor by Raman spectroscopy
Publisher: Elsevier BV
Date: 02-2011
Low temperature bainitic ferrite: Evidence of carbon super-saturation and tetragonality
Publisher: Elsevier BV
Date: 06-2015
Grain growth and dislocation density evolution in a nanocrystalline Ni-Fe alloy induced by high-pressure torsion
Publisher: Elsevier BV
Date: 02-2011
Soft magnetic properties of Ge-doped nanocrystalline Fe–Zr–B alloys
Publisher: Elsevier BV
Date: 2003
Atom probe study of chromium oxide spinels formed during intergranular corrosion
Publisher: Elsevier BV
Date: 04-2015
Three-dimensional shear-strain patterns induced by high-pressure torsion and their impact on hardness evolution
Publisher: Elsevier BV
Date: 06-2011
Rheology and 3D Printability of Percolated Graphene–Polyamide-6 Composites
Publisher: MDPI AG
Date: 03-09-2020
Abstract: Graphene–polyamide-6 (PA6) composites with up to 17.0%·w/w graphene content were prepared via melt mixing. Oscillatory rheometry revealed that the dynamic viscoelastic properties of PA6 decreased with the addition of 0.1%·w/w graphene but increased when the graphene content was increased to 6.0%·w/w and higher. Further analysis indicated that the rheological percolation threshold was between 6.0 and 10.0%·w/w graphene. The Carreau–Yasuda model was used to describe the complex viscosity of the materials. Capillary rheometry was applied to assess the steady shear rheology of neat PA6 and the 17.0%·w/w graphene–PA6 composite. High material viscosity at low shear rates coupled with intense shear-thinning in the composite highlighted the importance of selecting the appropriate rheological characterisation methods, shear rates and rheological models when assessing the 3D printability of percolated graphene–polymer composites for material extrusion (ME). A method to predict the printability of an ME filament feedstock, based on fundamental equations describing material flow through the printer nozzle, in the form of a printing envelope, was developed and verified experimentally. It was found that designing filaments with steady shear viscosities of approximately 15% of the maximum printable viscosity for the desired printing conditions will be advantageous for easy ME processing.
Magnetic, electrochemical and thermoelectric properties of P2-Nax (Co7/8 Sb1/8 )O2
Publisher: Elsevier BV
Date: 11-2017
Investigation of Self-assembled Monolayer by Atom Probe Microscopy
Publisher: Oxford University Press (OUP)
Date: 07-2009
DOI: 10.1017/S1431927609093003
Abstract: Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009
Electrodeposited PEDOT films on ITO with a flower-like hierarchical structure
Publisher: Elsevier BV
Date: 08-2010
Strengthening of an Al–Cu–Mg alloy processed by high-pressure torsion due to clusters, defects and defect–cluster complexes
Publisher: Elsevier BV
Date: 03-2015
Texture evolution in a CrMnFeCoNi high-entropy alloy manufactured by laser powder bed fusion
Publisher: Springer Science and Business Media LLC
Date: 04-03-2022
DOI: 10.1007/S10853-022-07025-X
Abstract: Additive manufacturing (AM) techniques including laser powder bed fusion have been widely used to produce metallic components with microstructures and mechanical properties distinctly different from the conventionally manufactured counterparts. Understanding how AM parameters affect the evolution of microstructure, including texture, of these AM metallic components is critical for appropriate manipulation of their processing and therefore their mechanical properties. Here we conducted a systematic investigation of texture evolution of a face-centred cubic CrMnFeCoNi high-entropy alloy cuboid fabricated using laser powder bed fusion. Our results showed that the texture evolutions along the build direction were different between the corner and central parts of the s le. Detailed analysis suggested that the texture evolution is closely related to local thermal gradient, which is a property that can be manipulated through changing AM parameters. The different textures lead to the significant variations of mechanical properties within the s le.
Resolving the morphology of niobium carbonitride nano-precipitates in steel using atom probe tomography
Publisher: Oxford University Press (OUP)
Date: 29-07-2014
DOI: 10.1017/S1431927614012872
Abstract: Atom probe is a powerful technique for studying the composition of nano-precipitates, but their morphology within the reconstructed data is distorted due to the so-called local magnification effect. A new technique has been developed to mitigate this limitation by characterizing the distribution of the surrounding matrix atoms, rather than those contained within the nano-precipitates themselves. A comprehensive chemical analysis enables further information on size and chemistry to be obtained. The method enables new insight into the morphology and chemistry of niobium carbonitride nano-precipitates within ferrite for a series of Nb-microalloyed ultra-thin cast strip steels. The results are supported by complementary high-resolution transmission electron microscopy.
The anatomy of grain boundaries: Their structure and atomic-level solute distribution
Publisher: Elsevier BV
Date: 10-2013
Bio-composites based on cellulose acetate and kenaf fibers: Processing and properties
Publisher: American Institute of Physics
Date: 2014
DOI: 10.1063/1.4873798
Effect of additions of Si and Ag to ternary Al-Cu-Mg alloys in the α + S phase field
Publisher: Elsevier BV
Date: 10-1996
High-density, vertically aligned crystalline CrO2 nanorod arrays derived from chemical vapor deposition assisted by AAO templates
Publisher: Royal Society of Chemistry (RSC)
Date: 2009
DOI: 10.1039/B905308E
Abstract: Vertically aligned CrO(2) nanorods with an areal density as high as 1.2 x 10(10) cm(-2) were obtained via atmospheric pressure CVD assisted by AAO templates for the first time.
One-Step Synthesis and Structural Features of CdS/Montmorillonite Nanocomposites
Publisher: American Chemical Society (ACS)
Date: 20-01-2005
DOI: 10.1021/JP046541I
Abstract: A novel synthesis method was introduced for the nanocomposites of cadmium sulfide and montmorillonite. This method features the combination of an ion exchange process and an in situ hydrothermal decomposition process of a complex precursor, which is simple in contrast to the conventional synthesis methods that comprise two separate steps for similar nanocomposite materials. Cadmium sulfide species in the composites exist in the forms of pillars and nanoparticles, the crystallized sulfide particles are in the hexagonal phase, and the sizes change when the amount of the complex for the synthesis is varied. Structural features of the nanocomposites are similar to those of the clay host but changed because of the introduction of the sulfide into the clay.
Three-dimensional electrodes for dye-sensitized solar cells: synthesis of indium–tin-oxide nanowire arrays and ITO/TiO2core–shell nanowire arrays by electrophoretic deposition
Publisher: IOP Publishing
Date: 12-01-2009
DOI: 10.1088/0957-4484/20/5/055601
Abstract: Dye-sensitized solar cells (DSSCs) show promise as a cheaper alternative to silicon-based photovoltaics for specialized applications, provided conversion efficiency can be maximized and production costs minimized. This study demonstrates that arrays of nanowires can be formed by wet-chemical methods for use as three-dimensional (3D) electrodes in DSSCs, thereby improving photoelectric conversion efficiency. Two approaches were employed to create the arrays of ITO (indium-tin-oxide) nanowires or arrays of ITO/TiO(2) core-shell nanowires both methods were based on electrophoretic deposition (EPD) within a polycarbonate template. The 3D electrodes for solar cells were constructed by using a doctor-blade for coating TiO(2) layers onto the ITO or ITO/TiO(2) nanowire arrays. A photoelectric conversion efficiency as high as 4.3% was achieved in the DSSCs made from ITO nanowires this performance was better than that of ITO/TiO(2) core-shell nanowires or pristine TiO(2) films. Cyclic voltammetry confirmed that the reaction current was significantly enhanced when a 3D ITO-nanowire electrode was used. Better separation of charge carriers and improved charge transport, due to the enlarged interfacial area, are thought to be the major advantages of using 3D nanowire electrodes for the optimization of DSSCs.
Statistical Tools for the Local Electrode Atom Probe
Publisher: Oxford University Press (OUP)
Date: 31-07-2006
DOI: 10.1017/S1431927606068346
Abstract: Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2005
Magnetotransport dependence on the field magnitude and direction in large area epitaxial graphene film on stretchable substrates
Publisher: AIP Publishing
Date: 04-03-2013
DOI: 10.1063/1.4794868
Abstract: We report the magnetotransport properties of large area graphene on stretchable polyethylene terephthalate substrates. At 2 K, weak localization of electrons introduced negative magnetoresistance at low field a transition to positive magnetoresistance followed as the external field increases. Our results suggest that weak localization contributes to Hall effect at low temperature. At room temperature, only classical Lorentz force contribution can be observed. Angular dependence of the external magnetic field on longitudinal and transverse resistivity is measured to test the interplay between weak localization and Lorentz force contribution. Quantitative simulations based on quantum interference theory produced excellent agreement with the experiments.
Manipulating ferroelectric behaviors via electron-beam induced crystalline defects
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1NR04300E
Abstract: We show a new way to tune ferroelectric behaviors in ferroelectric nanoplates by electron beam irradiation.
New insights into the phase transformations to isothermal ω and ω-assisted α in near β-Ti alloys
Publisher: Elsevier BV
Date: 03-2016
Environmental impact of discarded apparel landfilling and recycling
Publisher: Elsevier BV
Date: 03-2021
Minimizing and Controlling Hydrogen for Highly Efficient Formamidinium Lead Triiodide Solar Cells
Publisher: American Chemical Society (ACS)
Date: 06-04-2022
DOI: 10.1021/JACS.2C00038
Abstract: Formamidinium lead triiodide (FAPbI
Temperature-dependent-composition of η phase in an Al-Zn-Mg-Cu alloy under high pressure torsion: Kinetics and thermodynamics
Publisher: Elsevier BV
Date: 09-2022
Origin of the initial rapid age hardening in an Al-1.7 at.% Mg-1.1 at.% Cu alloy
Publisher: Informa UK Limited
Date: 09-1999
High On/Off Conductance Switching Ratio via H-Tautomerization in Quinone
Publisher: American Chemical Society (ACS)
Date: 07-08-2015
Abstract: Through first-principles electron transport simulations using the nonequilibrium Green's function formalism together with density functional theory, we show that, upon H-tautomerization, a simple derivative of quinone can act as a molecular switch with high ON/OFF ratio, up to 70 at low bias voltage. This switching behavior is explained by the quantum interference effect, where the positional change of hydrogen atoms causes the energies of the transmission channels to overlap. Our results suggest that this molecule could have potential applications as an effective switching device.
Room-temperature ferromagnetism and the scaling relation between magnetization and average granule size in nanocrystalline Zn/ZnO core-shell structures prepared by sputtering
Publisher: IOP Publishing
Date: 16-03-2010
DOI: 10.1088/0957-4484/21/14/145705
Abstract: Ferromagnetism is found in nanocrystalline Zn/ZnO core-shell structures prepared by sputtering pure Zn with subsequent oxidation. The saturation magnetization (M(S)) of the passivated ZnO shells increases with decrease in average particle size (d). The Curie temperature of the s les is above 400 degrees C. It is found that the ferromagnetism has a close relationship with point defects in ZnO shells. The maximum magnetization is estimated to be 28 emu cm(-3) (i.e. 0.14 mu(B) per unit cell) at 300 K, which is over three orders of magnitude larger than that of undoped ZnO nanoparticles or nanorods (10(-3)-10(-2) emu cm(-3)). More importantly, there is a scaling relation of M(s) alpha 1/d(n) (n = 5.20 +/- 0.20) for s les with d <or= 76 nm despite substantial differences in the particle size and shape. The results suggest that defects at the interface of the Zn/ZnO heterostructure make the main magnetic contributions.
Cellulose fibre-cellulose acetate hybrid composites with nanosilica
Publisher: Walter de Gruyter GmbH
Date: 04-2014
DOI: 10.1515/POLYENG-2013-0168
Abstract: Biocomposites incorporating cellulose fibres, a renewable resource, have high modulus and strength and flexibility suitable for structural applications. Solution casting, ultrasonication, and compression moulding methods were used to prepare the specimens. Results show that plasticiser indeed improved the flexibility of the composite and adding fillers further enhanced the performance of the composite.
Enhancement of the catalytic performance of a CNT supported Pt nanorod cluster catalyst by controlling their microstructure
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5RA13373D
Abstract: Novel catalysts with Pt nanorod clusters distributed in both interior and exterior of CNTs were prepared and confirmed by TEM tomography. This structure benefits higher performance due to the CNTs' confinement effect.
Effects of microalloying with Cd and Ag on the precipitation process of Al–4Cu–0.3Mg (wt%) alloy at 200°C
Publisher: Elsevier BV
Date: 2001
Effect of aging and deformation on the microstructure and properties of Fe−Ni−Ti maraging steel
Publisher: Springer Science and Business Media LLC
Date: 03-2004
Microstructural investigation of Ti–Si–N hard coatings
Publisher: Elsevier BV
Date: 07-2010
Applied stress controls the production of nano-twins in coarse-grained metals
Publisher: AIP Publishing
Date: 03-12-2012
DOI: 10.1063/1.4769216
Abstract: We present evidence that the level of the applied stress plays a critical role in deformation twinning in face-centred cubic alloys. While conventional cold rolling of a face-centred cubic structure produces a microstructure with a high-density of extended dislocations, increasing the applied stress using high-pressure torsion gives a nano-twinned coarse-grained structure. This suggests the existence of a critical stress for deformation twinning which thereby delineates an approach for the production of nano-twinned microstructures in coarse-grained materials with superior mechanical properties.
Visualizing plasmon coupling in closely spaced chains of Ag nanoparticles by electron energy-loss spectroscopy
Publisher: Wiley
Date: 27-01-2010
Abstract: Anisotropic plasmon coupling in closely spaced chains of Ag nanoparticles is visualized using electron energy-loss spectroscopy in a scanning transmission electron microscope. For dimers as the simplest chain, mapping the plasmon excitations with nanometer spatial resolution and an energy resolution of 0.27 eV intuitively identifies two coupling plasmons. The in-phase mode redshifts from the ultraviolet region as the interparticle spacing is reduced, reaching the visible range at 2.7 eV. Calculations based on the discrete-dipole approximation confirm its optical activeness, where the longitudinal direction is constructed as the path for light transportation. Two coupling paths are then observed in an inflexed four-particle chain.
Formation of Colloidal Hydroxy-Sodalite Nanocrystals by the Direct Transformation of Silicalite Nanocrystals
Publisher: American Chemical Society (ACS)
Date: 17-02-2006
DOI: 10.1021/CM052731+
An automated method of quantifying ferrite microstructures using electron backscatter diffraction (EBSD) data
Publisher: Elsevier BV
Date: 02-2014
DOI: 10.1016/J.ULTRAMIC.2013.11.003
Abstract: The identification and quantification of the different ferrite microconstituents in steels has long been a major challenge for metallurgists. Manual point counting from images obtained by optical and scanning electron microscopy (SEM) is commonly used for this purpose. While classification systems exist, the complexity of steel microstructures means that identifying and quantifying these phases is still a great challenge. Moreover, point counting is extremely tedious, time consuming, and subject to operator bias. This paper presents a new automated identification and quantification technique for the characterisation of complex ferrite microstructures by electron backscatter diffraction (EBSD). This technique takes advantage of the fact that different classes of ferrite exhibit preferential grain boundary misorientations, aspect ratios and mean misorientation, all of which can be detected using current EBSD software. These characteristics are set as criteria for identification and linked to grain size to determine the area fractions. The results of this method were evaluated by comparing the new automated technique with point counting results. The technique could easily be applied to a range of other steel microstructures.
Hollow nitrogen-containing core/shell fibrous carbon nanomaterials as support to platinum nanocatalysts and their TEM tomography study
Publisher: Springer Science and Business Media LLC
Date: 02-03-2012
Abstract: Core/shell nanostructured carbon materials with carbon nanofiber (CNF) as the core and a nitrogen (N)-doped graphitic layer as the shell were synthesized by pyrolysis of CNF olyaniline (CNF/PANI) composites prepared by in situ polymerization of aniline on CNFs. High-resolution transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared and Raman analyses indicated that the PANI shell was carbonized at 900°C. Platinum (Pt) nanoparticles were reduced by formic acid with catalyst supports. Compared to the untreated CNF/PANI composites, the carbonized composites were proven to be better supporting materials for the Pt nanocatalysts and showed superior performance as catalyst supports for methanol electrochemical oxidation. The current density of methanol oxidation on the catalyst with the core/shell nanostructured carbon materials is approximately seven times of that on the catalyst with CNF/PANI support. TEM tomography revealed that some Pt nanoparticles were embedded in the PANI shells of the CNF/PANI composites, which might decrease the electrocatalyst activity. TEM-energy dispersive spectroscopy mapping confirmed that the Pt nanoparticles in the inner tube of N-doped hollow CNFs could be accessed by the Nafion ionomer electrolyte, contributing to the catalytic oxidation of methanol.
Atom probe tomography of metallic nanostructures
Publisher: Springer Science and Business Media LLC
Date: 2016
DOI: 10.1557/MRS.2015.314
Carbon Nanomaterials in Biosensors: Should You Use Nanotubes or Graphene?
Publisher: Wiley
Date: 15-03-2010
Abstract: From diagnosis of life-threatening diseases to detection of biological agents in warfare or terrorist attacks, biosensors are becoming a critical part of modern life. Many recent biosensors have incorporated carbon nanotubes as sensing elements, while a growing body of work has begun to do the same with the emergent nanomaterial graphene, which is effectively an unrolled nanotube. With this widespread use of carbon nanomaterials in biosensors, it is timely to assess how this trend is contributing to the science and applications of biosensors. This Review explores these issues by presenting the latest advances in electrochemical, electrical, and optical biosensors that use carbon nanotubes and graphene, and critically compares the performance of the two carbon allotropes in this application. Ultimately, carbon nanomaterials, although still to meet key challenges in fabrication and handling, have a bright future as biosensors.
Solid phase mechanochemical synthesis of polyaniline branched nanofibers
Publisher: Elsevier BV
Date: 07-2009
Integrative Atom Probe Tomography Using Scanning Transmission Electron Microscopy-Centric Atom Placement as a Step Toward Atomic-Scale Tomography
Publisher: Oxford University Press (OUP)
Date: 20-01-2021
Electro-synthesis of novel nanostructured PEDOT films and their application as catalyst support
Publisher: Springer Science and Business Media LLC
Date: 27-04-2011
Abstract: Poly(3,4-ethylenedioxythiophene) (PEDOT) films doped with nitric and chlorine ions have been electrochemically deposited simply by a one-step electrochemical method in an aqueous media in the absence of any surfactant. The fabricated PEDOT films were characterized by scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The results indicate that the hierarchical structured PEDOT film doped with nitric ions displays a 'lunar craters' porous morphology consisting of PEDOT nano-sheets with a thickness of less than 2 nm. The effect of counter ions on the electro-polymerization, the electrochemistry, and the morphology of the polymer film was studied. Compared with PEDOT film doped with nitric acid, PEDOT film deposited in the presence of chlorine ions shows irregular morphology and less electrochemical activity. The specific nanostructure of the polymer was further studied as catalyst support for platinum nanoparticles to methanol electro-oxidation.
Local electron tomography using angular variations of surface tangents: Stomo version 2
Publisher: Elsevier BV
Date: 03-2012
Intrinsic Ferromagnetism in the Diluted Magnetic SemiconductorCo :
Publisher:
American Physical Society (APS)
Date:
23-11-2016
Publisher: American Physical Society (APS)
Date: 23-11-2016
Applying computational geometry techniques for advanced feature analysis in atom probe data
Publisher: Elsevier BV
Date: 09-2013
DOI: 10.1016/J.ULTRAMIC.2013.03.004
Abstract: In this paper we present new methods for feature analysis in atom probe tomography data that have useful applications in materials characterisation. The analysis works on the principle of Voronoi subvolumes and piecewise linear approximations, and feature delineation based on the distance to the centre of mass of a subvolume (DCOM). Based on the coordinate systems defined by these approximations, two ex les are shown of the new types of analyses that can be performed. The first is the analysis of line-like-objects (i.e. dislocations) using both proxigrams and line-excess plots. The second is interfacial excess mapping of an InGaAs quantum dot.
The effects of a trace addition of silver upon elevated temperature ageing of an Al–Zn–Mg alloy
Publisher: Elsevier BV
Date: 2001
Dynamic precipitation, segregation and strengthening of an Al-Zn-Mg-Cu alloy (AA7075) processed by high-pressure torsion
Publisher: Elsevier BV
Date: 2019
Decomposition behaviour of amorphous Fe89 xZr7B3Cu1Gexalloys
Publisher: IOP Publishing
Date: 11-02-2004
Ultrafine pure aluminium through back pressure equal channel angular consolidation (BP-ECAC) of particles
Publisher: Springer Science and Business Media LLC
Date: 04-01-2007
Multiferroic crossover in perovskite oxides
Publisher: American Physical Society (APS)
Date: 29-04-2016
Investigating the microstructure and composition of cold gas-dynamic spray (CGDS) Ti powder deposited on Al 6063 substrate
Publisher: Elsevier BV
Date: 08-2010
Precipitation behaviors of cubic and tetragonal Zr-rich phase in Al-(Si-)Zr alloys
Publisher: Elsevier BV
Date: 07-2016
Reconstructing deep-time histories from integrated thermochronology: An example from southern Baffin Island, Canada
Publisher: Wiley
Date: 04-04-2019
DOI: 10.1111/TER.12386
Estimating the physical cluster-size distribution within materials using atom-probe
Publisher: Wiley
Date: 2011
DOI: 10.1002/JEMT.20958
Abstract: A limiting characteristic of the atom-probe technique is the nondetection of ions and this embodies a significant "missing information" problem in investigations of atomic clustering phenomena causing difficulty in the interpretation of any atom-probe experiment. It is shown that the measurable cluster-size distribution can be modeled by a mixed binomial distribution. A deconvolution method based upon expectation-maximization (EM) algorithm is presented to obtain the original physical distribution from an efficiency-degraded distribution, thereby providing means to calculate accurate cluster number densities from atom probe results. The accuracy of this restoration was predominantly dependent upon the detector efficiency and was proved to be highly accurate in the case of conventional atom-probe detector efficiencies (ε = 57%). Such considerations and measures are absolutely necessary when the number density of clusters and small precipitates is in any way regarded as important. We conclude that limitations in detector efficiency are more limiting for cluster-finding analyses via atom-probe techniques than spatial resolution issues, and therefore the current endeavors for improving detector technologies are well found.
Nanostructured Al-Al2O3 composite formed in situ during consolidation of ultrafine Al particles by back pressure equal channel angular pressing
Publisher: Elsevier BV
Date: 08-2009
Antiferromagnetic-coupling-induced magnetoresistance enhancement in Fe x (TiO2 )1-x films
Publisher: AIP Publishing
Date: 05-06-2006
DOI: 10.1063/1.2209880
Abstract: Fe-incorporated amorphous TiO2 films with different Fe volume fractions of 0.46⩽x⩽0.76 were deposited by cosputtering iron and Ti targets in an Ar+O2 mixture. X-ray diffraction and x-ray photoelectron spectroscopy analyses give a structure of nanosized Fe particles embedded in amorphous TiO2 matrix for the Fex(TiO2)1−x films. Magnetic measurements show antiferromagnetic coupling between nanoscaled Fe granules when x& .60. The magnetoresistance of Fe0.46(TiO2)0.54 is about −7.6% at room temperature, which increases dramatically with decreasing temperature below ∼100K and reaches −29.3% at 3K. This significant enhancement of magnetoresistance can be qualitatively explained by antiferromagnetic coupling between Fe granules.
Attractive-domain-wall-pinning controlled Sm-Co magnets overcome the coercivity-remanence trade-off
Publisher: Elsevier BV
Date: 02-2019
Quantitative measurement for the microstructural parameters of nano-precipitates in Al-Mg-Si-Cu alloys
Publisher: Elsevier BV
Date: 08-2016
Extreme Room Temperature Compression and Bending in Ferroelectric Oxide Pillars
Publisher: Research Square Platform LLC
Date: 06-2021
DOI: 10.21203/RS.3.RS-342103/V1
Abstract: Plastic deformation in ceramic materials is normally only observed in nanometre-sized s les. However, we have observed unprecedented levels of plasticity ( % plastic strain) and excellent elasticity (6% elastic strain) in perovskite oxide Pb(In 1/2 Nb 1/2 )O 3 -Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 (PIN-PMN-PT), under compression along pc pillars up to 2.1 μm in diameter. The extent of this deformation is much higher than has previously been reported for ceramic materials, and the s le size at which plasticity is observed is almost an order of magnitude larger. Bending tests also revealed over 8% flexural strain. Plastic deformation occurred by slip along {110} . Calculations indicate that the resulting strain gradients will give rise to extreme flexoelectric polarization. First principles models predict that a high concentration of oxygen vacancies (Vo) weaken the covalent/ionic bonds, giving rise to the unexpected plasticity. Mechanical testing on Vo-rich Mn-doped PIN-PMN-PT confirmed this prediction. These findings will facilitate the design of plastic ceramic materials and the development of flexoelectric-based nano-electromechanical systems.
Full tip imaging in atom probe tomography
Publisher: Elsevier BV
Date: 2013
DOI: 10.1016/J.ULTRAMIC.2012.08.014
Abstract: Atom probe tomography (APT) is capable of simultaneously revealing the chemical identities and three dimensional positions of in idual atoms within a needle-shaped specimen, but suffers from a limited field-of-view (FOV), i.e., only the core of the specimen is effectively detected. Therefore, the capacity to analyze the full tip is crucial and much desired in cases that the shell of the specimen is also the region of interest. In this paper, we demonstrate that, in the analysis of III-V nanowires epitaxially grown from a substrate, the presence of the flat substrate positioned only micrometers away from the analyzed tip apex alters the field distribution and ion trajectories, which provides extra image compression that allows for the analysis of the entire specimen. An array of experimental results, including field desorption maps, elemental distributions, and crystallographic features clearly demonstrate the fact that the whole tip has been imaged, which is confirmed by electrostatic simulations.
Microstructure analysis of silicon nanocrystals formed from silicon rich oxide with high excess silicon: Annealing and doping effects
Publisher: AIP Publishing
Date: 10-07-2017
DOI: 10.1063/1.4990983
Abstract: Thin films consisting of silicon nanocrystals fabricated by high silicon content in silicon rich oxide show unique properties of decreasing resistivity and increasing light absorption while maintaining quantum confinement effects. With that said, the effect of the annealing temperature and doping element on the microscopic structure of silicon nanocrystals (Si NCs) and the film are still under research. In this study, in idual intrinsic, boron-, and phosphorus-doped films are annealed at various temperatures, and their structural properties are analyzed via atom probe tomography together with glancing incidence x-ray diffraction, Raman spectroscopy (Raman), transmission electron microscopy (TEM), and energy filtered TEM. In addition, photoluminescence (PL) is performed and linked with their microstructural properties. The Si NC growth is confirmed at annealing temperatures of 1000 °C and 1100 °C. The microstructure of the Si NCs in the whole film is dramatically changed by increasing the annealing temperature from 1000 °C to 1100 °C. In addition, doping changes the arrangement of the Si NCs by assisting their penetration across the SiO2 barrier layers. This study helps to understand the relationship between the microscopic and macroscopic properties of the Si NC film, showing that the size and distribution of the Si NCs are correlated with the obtained PL profiles.
Theory of solute clustering in materials for atom probe
Publisher: Informa UK Limited
Date: 15-03-2011
Structural and electronic properties of Eu- and Pd-doped ZnO
Publisher: Springer Science and Business Media LLC
Date: 21-04-2011
Abstract: Doping ZnO with rare earth and 4d transition elements is a popular technique to manipulate the optical properties of ZnO systems. These systems may also possess intrinsic ferromagnetism due to their magnetic moment borne on 4 f and 4 d electrons. In this work, the structural, electronic, and magnetic properties of Eu- and Pd-doped ZnO were investigated by the ab initio density functional theory methods based on generalized gradient approximation. The relative stability of incorporation sites of the doped elements in the ZnO host lattice was studied. The ground state properties, equilibrium bond lengths, and band structures of both the ZnO:Eu and ZnO:Pd systems were also investigated. The total and partial densities of electron states were also determined for both systems. It was found that in the ZnO:Eu system, ambient ferromagnetism can be induced by introducing Zn interstitial which leads to a carrier-mediated ferromagnetism while the ZnO:Pd system possesses no ferromagnetism. PACS 31.15.E-, 75.50.Pp, 75.30Hx
Influence of oxygen partial pressure on the ferromagnetic properties of polycrystalline Cr-doped ZnO films
Publisher: IOP Publishing
Date: 10-2008
Preferential nucleation and growth of InAs/GaAs(0 0 1) quantum dots on defected sites by droplet epitaxy
Publisher: Elsevier BV
Date: 10-2013
Room-temperature-deformation-induced chemical short-range ordering in a supersaturated ultrafine-grained Al-Zn alloy
Publisher: Elsevier BV
Date: 03-2022
Quantitative description of atomic architecture in solid solutions: A generalized theory for multicomponent short-range order
Publisher: American Physical Society (APS)
Date: 11-10-2010
The effect of clustering on the mobility of dislocations during aging in Nb-microalloyed strip cast steels: In situ heating TEM observations
Publisher: Elsevier BV
Date: 09-2013
Interstitial Hydrogen Anions: A Cause of p-Type Conductivity in CsSnI3
Publisher: American Chemical Society (ACS)
Date: 25-08-2022
Eu-doped boron nitride nanotubes as a nanometer-sized visible-light source
Publisher: Wiley
Date: 16-07-2007
Controlling the relaxation versus rejuvenation behavior in Zr-based bulk metallic glasses induced by elastostatic compression
Publisher: Elsevier BV
Date: 10-2022
Analysis of strengthening in AA6111 during the early stages of aging: Atom probe tomography and yield stress modelling
Publisher: Elsevier BV
Date: 11-2013
Field evaporation behavior in [001] FePt thin films
Publisher: Elsevier BV
Date: 05-2011
DOI: 10.1016/J.ULTRAMIC.2010.12.027
Abstract: Though the atom probe has provided unprecedented atomic identification and spatial imaging capability, the basic reconstruction assumption of a smooth hemispherical tip shape creates significant challenges in yielding high fidelity chemical information for atomic species with extreme differences in fields required for field evaporation. In the present study, the evaporation behavior and accompanying artifacts are examined for the super-cell lattice structure of L1(0) FePt, where alternating Fe and Pt planes exist in the [0 0 1] orientation. Elemental Fe and Pt have significant differences in field strengths providing a candidate system to quantify these issues. Though alloys can result in changes in the elemental field strength, the intrinsic nature of elemental planes in [0 0 1] L1(0) provides a system to determine to what extent basic assumptions of elemental field strengths can break down in understanding reconstruction artifacts in this intermetallic alloy. The reconstruction of field evaporation experiments has shown depletion of Fe at the (0 0 2) pole and zone axes. Compositional profiles revealed an increase in Fe and atom count moving outward from the pole. The depletion at the low indexed pole and zone axes was determined to be the result of local magnification and electrostatic effects. The experimental results are compared to an electrostatic simulation model.
Study the electronic responses of individual nanoparticles by electron energy loss spectroscopy in a transmission electron microscope
Publisher: IEEE
Date: 10-2010
Communication: Electrical rectification of C59 N: The role of anchoring and doping sites
Publisher: AIP Publishing
Date: 14-01-2016
DOI: 10.1063/1.4940142
Abstract: Based on the nonequilibrium Green’s function formalism and density-functional theory, we investigate the onset of electrical rectification in a single C59N molecule in conjunction with gold electrodes. Our calculations reveal that rectification is dependent upon the anchoring of the Au atom on C59N when the Au electrode is singly bonded to a C atom (labeled here as A), the system does not exhibit rectification, whereas when the electrode is connected to the C–C bridge site between two hexagonal rings (labeled here as B), transmission asymmetry is observed, where the rectification ratio reaches up to 2.62 at ±1 V depending on the N doping site relative to the anchoring site. Our analysis of the transmission mechanism shows that N doping of the B configuration causes rectification because more transmission channels are available for transmission in the B configuration than in the A configuration.
Introducing a Crystallography-Mediated Reconstruction (CMR) Approach to Atom Probe Tomography
Publisher: Oxford University Press (OUP)
Date: 04-02-2019
DOI: 10.1017/S1431927618015593
Abstract: Current approaches to reconstruction in atom probe tomography produce results that exhibit substantial distortions throughout the analysis depth. This is largely because of the need to apply a multitude of assumptions when estimating the evolution of the tip shape, and other pseudo-empirical reconstruction factors, which vary both across the face of the tip and throughout the analysis depth. We introduce a new crystallography-mediated reconstruction to improve the spatial accuracy and dramatically reduce these in-depth variations. To achieve this, we developed a barycentric transform to directly relate atomic positions in detector space to real space. This is mediated by novel crystallographic analysis techniques, including: (1) calculating the orientation of a crystal directly from the field evaporation map, (2) tracking pole locations throughout the evaporation sequence, and (3) accounting for the evolving tip radius in a manner that removes the dependence on the geometric field factor. By improving the in-depth spatial accuracy of the atom probe reconstruction, a greater accuracy of the atomic neighborhood relationships is available. This is critical in modern materials science and engineering, where an understanding of the solid solution architecture, precipitate dispersions, and descriptions of the interfaces between phases or grains are key inputs to microstructure–property relationships.
Controlled synthesis and characterization of 10 nm thick Al2O3 nanowires
Publisher: Elsevier BV
Date: 05-2009
Direct synthesis and strong cathodoluminescence of Al2O3 nanotubes
Publisher: Elsevier BV
Date: 04-2010
Estimation of the Reconstruction Parameters for Atom Probe Tomography
Publisher: Oxford University Press (OUP)
Date: 04-07-2008
DOI: 10.1017/S1431927608080690
Abstract: The application of wide field-of-view detection systems to atom probe experiments emphasizes the importance of careful parameter selection in the tomographic reconstruction of the analyzed volume, as the sensitivity to errors rises steeply with increases in analysis dimensions. In this article, a self-consistent method is presented for the systematic determination of the main reconstruction parameters. In the proposed approach, the compression factor and the field factor are determined using geometrical projections from the desorption images. A three-dimensional Fourier transform is then applied to a series of reconstructions, and after comparing to the known material crystallography, the efficiency of the detector is estimated. The final results demonstrate a significant improvement in the accuracy of the reconstructed volumes.
On the mechanism of Mn partitioning during intercritical annealing in medium Mn steels
Publisher: Elsevier BV
Date: 02-2022
Structural, optical, and electrical properties of silicon nanocrystals fabricated by high silicon content silicon-rich oxide and silicon dioxide bilayers
Publisher: IOP Publishing
Date: 17-10-2016
Abstract: Intrinsic, boron (B)-doped, and phosphorus (P)-doped silicon nanocrystals (Si NCs) formed from an excess Si concentration of 40 at. % were investigated to study their structural, optical, and electrical properties. Atom probe tomography (APT) revealed that the size and arrangement of Si NCs were different in each s le. A strong blue shift in photoluminescence spectra for the intrinsic and B-doped Si NCs was correlated with the volume fraction of small Si NCs. The lower resistivity of the B-doped s le than the P-doped one was explained by the percolation of Si NCs through the film.
Quantitative atom probe analysis of nanostructure containing clusters and precipitates with multiple length scales
Publisher: Elsevier BV
Date: 05-2011
DOI: 10.1016/J.ULTRAMIC.2010.12.029
Abstract: A model Al-3 Cu-(0.05 Sn) (wt%) alloy containing a bimodal distribution of relatively shear-resistant θ' precipitates and shearable GP zones is considered in this study. It has recently been shown that the addition of the GP zones to such microstructures can lead to significant increases in strength without a decrease in the uniform elongation. In this study, atom probe tomography (APT) has been used to quantitatively characterise the evolution of the GP zones and the solute distribution in the bimodal microstructure as a function of applied plastic strain. Recent nuclear magnetic resonance (NMR) analysis has clearly shown strain-induced dissolution of the GP zones, which is supported by the current APT data with additional spatial information. There is significant repartitioning of Cu from the GP zones into the solid solution during deformation. A new approach for cluster finding in APT data has been used to quantitatively characterise the evolution of the sizes and shapes of the Cu containing features in the solid solution solute as a function of applied strain.
On dysprosium utilisation in multi-main-phase Nd–Dy–Fe–B magnets with core–shell microstructures
Publisher: Elsevier BV
Date: 12-2023
Applications of Spatial Distribution Maps for Advanced Atom Probe Reconstruction and Data Analysis
Publisher: Oxford University Press (OUP)
Date: 07-2009
DOI: 10.1017/S1431927609092599
Abstract: Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009
Hydrogen adsorption capacity of adatoms on double carbon vacancies of graphene: A trend study from first principles
Publisher: American Physical Society (APS)
Date: 03-01-2013
Quantitative Determination of How Growth Conditions Affect the 3D Composition of InGaAs Nanowires
Publisher: Oxford University Press (OUP)
Date: 18-02-2019
DOI: 10.1017/S1431927619000114
Abstract: Covering a broad optical spectrum, ternary In x Ga 1− x As nanowires, grown by bottom-up methods, have been receiving increasing attention due to the tunability of the bandgap via In composition modulation. However, inadequate knowledge about the correlation between growth and properties restricts our ability to take advantage of this phenomenon for optoelectronic applications. Here, three different InGaAs nanowires were grown under different experimental conditions and atom probe tomography was used to quantify their composition, allowing the direct observation of the nanowire composition associated with the different growth conditions.
Mechanisms for enhanced plasticity in magnesium alloys
Publisher: Elsevier BV
Date: 2015
Mechanical behaviors of as-deposited and annealed nanostructured Ni-Fe alloys
Publisher: Elsevier BV
Date: 06-2011
Solute clustering, segregation and microstructure in high strength low alloy Al–Cu–Mg alloys
Publisher: Elsevier BV
Date: 07-1998
Formation and 3D morphology of interconnected α microstructures in additively manufactured Ti-6Al-4V
Publisher: Elsevier BV
Date: 12-2021
Nanocrystalline β-Ti alloy with high hardness, low Young's modulus and excellent in vitro biocompatibility for biomedical applications
Publisher: Elsevier BV
Date: 08-2013
DOI: 10.1016/J.MSEC.2013.04.044
Abstract: High strength, low Young's modulus and good biocompatibility are desirable but difficult to simultaneously achieve in metallic implant materials for load bearing applications, and these impose significant challenges in material design. Here we report that a nano-grained β-Ti alloy prepared by high-pressure torsion exhibits remarkable mechanical and biological properties. The hardness and modulus of the nano-grained Ti alloy were respectively 23% higher and 34% lower than those of its coarse-grained counterpart. Fibroblast cell attachment and proliferation were enhanced, demonstrating good in vitro biocompatibility of the nano-grained Ti alloy, consistent with demonstrated increased nano-roughness on the nano-grained Ti alloy. Results suggest that the nano-grained β-Ti alloy may have significant application as an implant material in dental and orthopedic applications.
Communication: Solute diffusion characteristics of a rapid hardening Al-Cu-Mg alloy during the early stages of age hardening
Publisher: Springer Science and Business Media LLC
Date: 26-05-2010
Multimodal γ′ precipitation in Inconel-738 Ni-based superalloy during electron-beam powder bed fusion additive manufacturing
Publisher: Springer Science and Business Media LLC
Date: 10-06-2020
Optimisation of specimen temperature and pulse fraction in atom probe microscopy experiments on a microalloyed steel
Publisher: Elsevier BV
Date: 05-2011
DOI: 10.1016/J.ULTRAMIC.2010.12.032
Abstract: This paper details the effects of systematic changes to the experimental parameters for atom probe microscopy of microalloyed steels. We have used assessments of the signal-to-noise ratio (SNR), compositional measurements and field desorption images to establish the optimal instrumental parameters. These corresponded to probing at the lowest possible temperature (down to 20K) with the highest possible pulse fraction (up to 30%). A steel containing a fine dispersion of solute atom clusters was used as an archetype to demonstrate the importance of running the atom probe at optimum conditions.
A novel method for practical temperature measurement with carbon nanotube nanothermometers
Publisher: IOP Publishing
Date: 27-06-2006
Precipitation microstructure and their strengthening effects of an Mg-2.8Nd-0.6Zn-0.4Zr alloy with a 0.2 wt.% Y addition
Publisher: Elsevier BV
Date: 03-2012
Short-range order in multicomponent materials
Publisher: International Union of Crystallography (IUCr)
Date: 20-07-2012
A tool for scientific provenance of data and software
Publisher: IEEE
Date: 12-2013
DOI: 10.1109/CSE.2013.89
Stress/strain induced flux pinning in highly dense MgB2 bulks
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 06-2009
Precipitation processes in Al-Cu-Mg-Sn and Al-Cu-Mg-Sn-Ag
Publisher: Elsevier BV
Date: 04-2016
Influence of experimental parameters on the composition of precipitates in metallic alloys
Publisher: Elsevier BV
Date: 09-2013
DOI: 10.1016/J.ULTRAMIC.2013.02.005
Abstract: We report on the change in the shape, size and composition of spherical precipitates, found in an Fe-Cu and an Al-Ag alloy, as the base temperature, pulsing mode and parameters are adjusted. In the case of the Al-Ag alloy, the difference in the evaporation field between precipitates and matrix can be minimised at low temperature, while in the Fe-Cu alloy minimal changes are observed within the range of experimental conditions investigated. Comparison with transmission electron microscopy shows that some experimental conditions yield accurate precipitates size, while others enable reaching accurate composition measurements.
Strengthening brittle semiconductor nanowires through stacking faults: Insights from in situ mechanical testing
Publisher: American Chemical Society (ACS)
Date: 03-09-2013
DOI: 10.1021/NL402180K
Abstract: Quantitative mechanical testing of single-crystal GaAs nanowires was conducted using in situ deformation transmission electron microscopy. Both zinc-blende and wurtzite structured GaAs nanowires showed essentially elastic deformation until bending failure associated with buckling occurred. These nanowires fail at compressive stresses of ~5.4 GPa and 6.2 GPa, respectively, which are close to those values calculated by molecular dynamics simulations. Interestingly, wurtzite nanowires with a high density of stacking faults fail at a very high compressive stress of ~9.0 GPa, demonstrating that the nanowires can be strengthened through defect engineering. The reasons for the observed phenomenon are discussed.
Crystallography of refractory metal nuggets in carbonaceous chondrites: A transmission Kikuchi diffraction approach
Publisher: Elsevier BV
Date: 11-2017
Improved PMI-based input variable selection approach for artificial neural network and other data driven environmental and water resource models
Publisher: Elsevier BV
Date: 03-2015
Role of stress-assisted martensite in the design of strong ultrafine-grained duplex steels
Publisher: Elsevier BV
Date: 2015
The effect of fast annealing treatment on the interface structure and electrical properties of Au/Hg3In2Te6 contact
Publisher: Springer Science and Business Media LLC
Date: 19-06-2014
Precipitation and solute clustering in aluminium: Advanced characterisation techniques
Publisher: Elsevier
Date: 2010
Shaping the lens of the atom probe: Fabrication of site specific, oriented specimens and application to grain boundary analysis
Publisher: Elsevier BV
Date: 05-2011
DOI: 10.1016/J.ULTRAMIC.2010.12.005
Abstract: The random s ling provided by classical atom probe s le preparation methods is one of the major factors limiting the types of problems that can be addressed using this powerful technique. A focused ion beam enables not only site-specific preparation, but can also be used to give the specimen, which acts as the lens in an atom probe experiment, a specific shape. In this paper we present a technique that uses low accelerating voltages (10 and 5 kV) in the focused ion beam (FIB) to reproducibly produce specimens with selected grain boundaries <100 nm from the tip at any desired orientation. These tips have a high rate of successfully running in the atom probe and no Ga contamination within the region of interest. This technique is applied to the analysis of grain boundaries in a high purity iron wire and a strip-cast steel. Lattice resolution is achieved around the boundary in certain areas. Reconstruction of these datasets reveals the distribution of light and heavy elements around the boundary. Issues surrounding the uneven distribution of certain solute elements as a result of field-induced diffusion are discussed.
Restoring the lattice of Si-based atom probe reconstructions for enhanced information on dopant positioning
Publisher: Elsevier BV
Date: 12-2015
DOI: 10.1016/J.ULTRAMIC.2015.05.011
Abstract: The following manuscript presents a novel approach for creating lattice based models of Sb-doped Si directly from atom probe reconstructions for the purposes of improving information on dopant positioning and directly informing quantum mechanics based materials modeling approaches. Sophisticated crystallographic analysis techniques are used to detect latent crystal structure within the atom probe reconstructions with unprecedented accuracy. A distortion correction algorithm is then developed to precisely calibrate the detected crystal structure to the theoretically known diamond cubic lattice. The reconstructed atoms are then positioned on their most likely lattice positions. Simulations are then used to determine the accuracy of such an approach and show that improvements to short-range order measurements are possible for noise levels and detector efficiencies comparable with experimentally collected atom probe data.
Atom probe tomography and transmission electron microscopy characterisation of precipitation in an Al-Cu-Li-Mg-Ag alloy
Publisher: Elsevier BV
Date: 05-2011
DOI: 10.1016/J.ULTRAMIC.2010.12.004
Abstract: State-of-the art atom probe tomography (APT) combined with transmission electron microscopy (TEM) were used to investigate the microstructure at different stages of the ageing process of an alloy of composition (at%) Al-1.68%Cu-4.62%Li-0.33%Mg-0.1%Ag. These alloys were shown to exhibit a complex microstructure of T(1) plates and several metastable phases, including θ' and S. We will highlight the early stages of clustering, precipitate interactions and possible solute segregation at the matrix recipitate interfaces and detail the chemical composition of the different phases.
TDDFT Study of the Optical Excitation of Nucleic Acid Bases-C60 Complexes
Publisher: American Chemical Society (ACS)
Date: 15-11-2017
Abstract: The potential of C
ONGOING DISCUSSION + SOVIET FORCED LABOR CAMPS
Publisher: Cambridge University Press (CUP)
Date: 1989
DOI: 10.2307/2499843
Atom probe microscopy characterization of as quenched Zr-0.8 wt% Fe and Zr-0.15 wt% Cr binary alloys
Publisher: Elsevier BV
Date: 2013
Large spin-filtering effect in Ti-doped defective zigzag graphene nanoribbon
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C6CP01601D
Abstract: We theoretically study the conductance of double-vacancy zigzag graphene nanoribbons doped with Ti, V, Cr and Fe, and find that Ti doping, despite possessing small spin moment at Ti site, induces large spin-filtering with an efficiency in excess of 90% for bias voltages below 0.5 V.
Multiple CO2 capture in stable metal-doped graphene: A theoretical trend study
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5RA09876A
Abstract: A systematic trend study of carbon dioxide capture on metal-doped single vacancy/double vacancy graphene.
Single-crystalline, submicrometer-sized ZnSe tubes
Publisher: Wiley
Date: 18-04-2005
Correlation between precipitates evolution and mechanical properties of Al-Sc-Zr alloy with Er additions
Publisher: Elsevier BV
Date: 02-2022
Multiple solution-doping in optical fibre fabrication II - Rare-earth and aluminium co-doping
Publisher: Elsevier BV
Date: 03-2008
Microstructural characterization and mechanical behaviours of TiN-graphite composites fabricated by spark plasma sintering
Publisher: Elsevier BV
Date: 09-2020
Quantitative dopant distributions in GaAs nanowires using atom probe tomography
Publisher: Elsevier BV
Date: 09-2013
DOI: 10.1016/J.ULTRAMIC.2013.02.012
Abstract: Controllable doping of semiconductor nanowires is critical to realize their proposed applications, however precise and reliable characterization of dopant distributions remains challenging. In this article, we demonstrate an atomic-resolution three-dimensional elemental mapping of pristine semiconductor nanowires on growth substrates by using atom probe tomography to tackle this major challenge. This highly transferrable method is able to analyze the full diameter of a nanowire, with a depth resolution better than 0.17 nm thanks to an advanced reconstruction method exploiting the specimen's crystallography, and an enhanced chemical sensitivity of better than 8-fold increase in the signal-to-noise ratio.
Spatial decomposition of molecular ions within 3D atom probe reconstructions
Publisher: Elsevier BV
Date: 09-2013
DOI: 10.1016/J.ULTRAMIC.2013.02.014
Abstract: Two methods for separating the constituent atoms of molecular ions within atom probe tomography reconstructions are presented. The Gaussian Separation Method efficiently deconvolutes molecular ions containing two constituent atoms and is tested on simulated data before being applied to an experimental HSLA steel dataset containing NbN. The Delaunay Separation Method extends separation to larger complex ions and is also tested on simulated data before being applied to an experimental GaAs dataset containing many large (>3 atoms) complex ions. First nearest neighbour (1NN) distributions and images of the reconstruction before and after the separations are used to show the effect of the algorithms and their validity and practicality are also discussed.
Advanced quantification of the site-occupancy in ordered multi-component intermetallics using atom probe tomography
Publisher: Elsevier BV
Date: 06-2022
Mechanism of grain growth during severe plastic deformation of a nanocrystalline Ni-Fe alloy
Publisher: AIP Publishing
Date: 05-01-2009
DOI: 10.1063/1.3065025
Abstract: Deformation induced grain growth has been widely reported in nanocrystalline materials. However, the grain growth mechanism remains an open question. This study applies high-pressure torsion to severely deform bulk nanocrystalline Ni-20 wt % Fe disks and uses transmission electron microscopy to characterize the grain growth process. Our results provide solid evidence suggesting that high pressure torsion induced grain growth is achieved primarily via grain rotation for grains much smaller than 100 nm. Dislocations are mainly seen at small-angle subgrain boundaries during the grain growth process but are seen everywhere in grains after the grains have grown large.
Electrical Conductivity Studies on Individual Conjugated Polymer Nanowires: Two-Probe and Four-Probe Results
Publisher: Springer Science and Business Media LLC
Date: 13-11-2010
DOI: 10.1007/S11671-009-9471-Y
Abstract: Two- and four-probe electrical measurements on in idual conjugated polymer nanowires with different diameters ranging from 20 to 190 nm have been performed to study their conductivity and nanocontact resistance. The two-probe results reveal that all the measured polymer nanowires with different diameters are semiconducting. However, the four-probe results show that the measured polymer nanowires with diameters of 190, 95–100, 35–40 and 20–25 nm are lying in the insulating, critical, metallic and insulting regimes of metal–insulator transition, respectively. The 35–40 nm nanowire displays a metal–insulator transition at around 35 K. In addition, it was found that the nanocontact resistance is in the magnitude of 10 4 Ω at room temperature, which is comparable to the intrinsic resistance of the nanowires. These results demonstrate that four-probe electrical measurement is necessary to explore the intrinsic electronic transport properties of isolated nanowires, especially in the case of metallic nanowires, because the metallic nature of the measured nanowires may be coved by the nanocontact resistance that cannot be excluded by a two-probe technique.
In situ self-assembly of thin ZnO nanoplatelets into hierarchical mesocrystal Microtubules with surface grafting of nanorods: A general strategy towards hollow mesocrystal structures
Publisher: Wiley
Date: 18-01-2008
Activity at the surface
Publisher: Springer Science and Business Media LLC
Date: 19-12-2017
DOI: 10.1038/NMAT5058
On the Role of Characterization in the Design of Interfaces in Nanoscale Materials Technology
Publisher: Oxford University Press (OUP)
Date: 06-2004
DOI: 10.1017/S1431927604040504
Abstract: This work reviews recent research on the design and control of interfaces in engineering nanomaterials. Four case studies are presented that demonstrate the power of a multimodal approach to the characterization of different types of interfaces. We have used a combination of conventional, high resolution, and analytical transmission electron microscopy, microbeam electron diffraction, and three-dimensional atom probe to study polymer–clay nanocomposites, turbine rotor steels used for power generation, multicomponent aluminum alloys, and nanocrystalline magnetic materials.
The role of vacancies in electric field mediated graphene oxide reduction
Publisher: AIP Publishing
Date: 13-08-2018
DOI: 10.1063/1.5039650
Abstract: Electric fields are regarded as a promising means of graphene oxide reduction, but previous studies have only focused on pristine graphene. Here, based on first principles density functional theory calculations, we report on electric field mediated reduction of neutral and charged O and hydroxyl groups from both pristine and defective graphene sheets. The critical electric field strengths for different species are determined in facilitating a progressive and selective graphene oxide reduction. Our results demonstrate that the presence of vacancy defects significantly inhibits the effectiveness of electric fields as a means of reduction of O and OH functionals, due to the complexities that arise between the functional group and vacancy edge atoms in the presence of an applied electric field.
Quantitative chemical-structure evaluation using atom probe tomography: Short-range order analysis of Fe-Al
Publisher: Elsevier BV
Date: 10-2015
DOI: 10.1016/J.ULTRAMIC.2015.05.001
Abstract: Short-range-order (SRO) has been quantitatively evaluated in an Fe-18Al (at%) alloy using atom probe tomography (APT) data and by calculation of the generalised multicomponent short-range order (GM-SRO) parameters, which have been determined by shell-based analysis of the three-dimensional atomic positions. The accuracy of this method with respect to limited detector efficiency and spatial resolution is tested against simulated D03 ordered data. Whilst there is minimal adverse effect from limited atom probe instrument detector efficiency, the combination of this with imperfect spatial resolution has the effect of making the data appear more randomised. The value of lattice rectification of the experimental APT data prior to GM-SRO analysis is demonstrated through improved information sensitivity.
Mining information from atom probe data
Publisher: Elsevier BV
Date: 12-2015
DOI: 10.1016/J.ULTRAMIC.2015.05.006
Abstract: Whilst atom probe tomography (APT) is a powerful technique with the capacity to gather information containing hundreds of millions of atoms from a single specimen, the ability to effectively use this information creates significant challenges. The main technological bottleneck lies in handling the extremely large amounts of data on spatial-chemical correlations, as well as developing new quantitative computational foundations for image reconstruction that target critical and transformative problems in materials science. The power to explore materials at the atomic scale with the extraordinary level of sensitivity of detection offered by atom probe tomography has not been not fully harnessed due to the challenges of dealing with missing, sparse and often noisy data. Hence there is a profound need to couple the analytical tools to deal with the data challenges with the experimental issues associated with this instrument. In this paper we provide a summary of some key issues associated with the challenges, and solutions to extract or "mine" fundamental materials science information from that data.
Extracting anisotropy energy barrier distributions of nanomagnetic systems from magnetization/susceptibility measurements
Publisher: Elsevier BV
Date: 05-2009
Atom probe analysis of clusters and precipitates in severely deformed and annealed interstitial free steel
Publisher: Informa UK Limited
Date: 04-2011
De-twinning via secondary twinning in face-centered cubic alloys
Publisher: Elsevier BV
Date: 08-2013
Origin of the spatial resolution in atom probe microscopy
Publisher: AIP Publishing
Date: 20-07-2009
DOI: 10.1063/1.3182351
Unconventional Ribbon-Shaped β-Ga2O3 Tubes with Mobile Sn Nanowire Fillings
Publisher: American Chemical Society (ACS)
Date: 22-12-2007
DOI: 10.1021/NN700285D
Abstract: We report on the synthesis of novel, unconventional beta-Ga(2)O(3) tubes via a Sn nanowire template process using thermal decomposition and oxidation of SnO and GaN powder mixtures. Distinctly different from any previously reported nano- and microtubes, the present beta-Ga(2)O(3) tubes display a flattened and thin belt-like (or ribbon-like) morphology. Each ribbon-shaped tube has a width of approximately 1-2 microm over its entire length, a length in the range of tens of micrometers, a thickness of approximately 100-150 nm, and a uniform inner diameter of 30-120 nm. The tubes were either partially or completely filled with Sn nanowires, forming Sn/Ga(2)O(3) metal-semiconductor nanowire heterostructures. A convergent electron beam generated in a transmission electron microscope is demonstrated to be an effective tool for delicate manipulation of encapsulated Sn nanowires. The Sn nanowires were gently cut apart (into two discrete fragments) and then completely separated and rejoined within Ga(2)O(3) ribbon-shaped tubes. These unconventional beta-Ga(2)O(3) tubes not only should enrich the well-established bank of nanostructured morphologies and extend the understanding of crystal growth at the nanoscale but also may have promise for the design of electron-beam-irradiation- or thermo-driven electrical switches.
Introduction to Atomic-Scale Tomography
Publisher: Oxford University Press (OUP)
Date: 22-07-2023
EFFECTS OF COLD WORK ON PRECIPITATION IN AL-CU-MG-(AG) AND AL-CU-LI-(MG-AG) ALLOYS
Publisher: Springer Science and Business Media LLC
Date: 07-1995
DOI: 10.1007/BF02670753
New Techniques for the Analysis of Fine-Scaled Clustering Phenomena within Atom Probe Tomography (APT) Data
Publisher: Oxford University Press (OUP)
Date: 14-11-2003
DOI: 10.1017/S1431927607070900
Abstract: Nanoscale atomic clusters in atom probe tomographic data are not universally defined but instead are characterized by the clustering algorithm used and the parameter values controlling the algorithmic process. A new core-linkage clustering algorithm is developed, combining fundamental elements of the conventional maximum separation method with density-based analyses. A key improvement to the algorithm is the independence of algorithmic parameters inherently unified in previous techniques, enabling a more accurate analysis to be applied across a wider range of material systems. Further, an objective procedure for the selection of parameters based on approximating the data with a model of complete spatial randomness is developed and applied. The use of higher nearest neighbor distributions is highlighted to give insight into the nature of the clustering phenomena present in a system and to generalize the clustering algorithms used to analyze it. Maximum separation, density-based scanning, and the core linkage algorithm, developed within this study, were separately applied to the investigation of fine solute clustering of solute atoms in an Al-1.9Zn-1.7Mg (at.%) at two distinct states of early phase decomposition and the results of these analyses were evaluated.
Qualification of the tomographic reconstruction in atom probe by advanced spatial distribution map techniques
Publisher: Elsevier BV
Date: 06-2009
DOI: 10.1016/J.ULTRAMIC.2009.03.016
Abstract: New and improved spatial distribution map (SDM) methods are developed to identify and extract crystallographic information within atom probe tomography three-dimensional (3D) reconstructions. Detailed structural information is retrieved by combining z-SDM offset distribution analyses computed in multiple crystallographic directions, accurately determining inter-planar spacings and crystallographic angles. The advantages of this technique in comparison to applying the complete z-SDM and complementary xy-SDM analysis to a single crystallographic direction are investigated. Further, in determining these multidirectional z-SDM and xy-SDM profiles, background noise reduction and automatic peak identification algorithms are adapted to attain increased accuracy and is shown to be particularly effective in cases where crystal structure is present but poorly resolved. These techniques may be used to calibrate the reconstruction parameters and investigate their dependence on the design of in idual atom probe experiments.
THE BEHAVIOR OF GALLIUM CONFINED IN CARBON NANOTUBES DURING HEATING AND COOLING
Publisher: World Scientific Pub Co Pte Lt
Date: 06-2008
DOI: 10.1142/S1793604708000101
Abstract: The thermal expansion of gallium ( Ga ) encapsulated in carbon nanotubes has been studied. It is demonstrated that the volumetric expansion and contraction of the Ga confined in the carbon nanotubes display a linear relationship with temperature. While the level of the tip of the Ga column changes linearly with temperature, it returns to its previous position, without any hysteresis, when reheated or cooled to the original temperature, provided the Ga has not frozen and electron-beam irradiation is minimized. It is shown that electron beam irradiation can cause shrinkage in carbon-nanotube diameter, and that a high-intensity electron beam can also induce the formation of new carbon shells inside the carbon nanotubes. Upon freezing, the solid Ga has two unique orientation relationships with the carbon nanotubes.
An initial report on achieving high comprehensive performance in an Al-Mg-Si alloy via novel thermomechanical processing
Publisher: Elsevier BV
Date: 10-2018
Design of Solute Clustering during Thermomechanical Processing of AA6016 Al-Mg-Si Alloy
Publisher: Elsevier BV
Date: 2020
DOI: 10.2139/SSRN.3614851
Coercivity degradation caused by inhomogeneous grain boundaries in sintered Nd-Fe-B permanent magnets
Publisher: American Physical Society (APS)
Date: 14-05-2018
Intragranular glass/crystal conjugated particles in strip cast Nd-Fe-B flakes
Publisher: Elsevier BV
Date: 02-2020
Valence excitations and dopant distribution of al doped zno nanowires analyzed by electron energy loss spectroscopy
Publisher: American Scientific Publishers
Date: 11-2011
Abstract: Valence electron energy loss spectroscopy (VEELS) with scanning transmission electron microscopy (STEM) has been employed to probe the valence excitations and dopant distribution of Al doped ZnO nanowires. The results reveal that while the typical Al concentration is on the order of 1020 1/cm3, Al tends to segregate at the surface leading to an Al-rich sheath. In VEEL spectra, O-2p, Zn-3d, Al-3p, O-2s, interband transitions as well as bulk plasmon have been identified. The bulk plasmon peak is blue-shifted, and the projected interband transition decreases from 2.14 to 1.88 eV as the doping concentration increases from 0.83 x 10(20) to 2.18 x 10(20) 1/cm3.
Single Crystal Kinked ZnO [001] and [110] Nanowires: Synthesis, Characterization, and Growth/Kinking Mechanism
Publisher: American Chemical Society (ACS)
Date: 02-05-2012
DOI: 10.1021/CG300328C
Ultrahigh specific strength in a magnesium alloy strengthened by spinodal decomposition
Publisher: American Association for the Advancement of Science (AAAS)
Date: 04-06-2021
Abstract: Spinodal decomposition is discovered to be an effective way to strengthen magnesium alloy.
Determination of Al compositional profiles across AlAs/GaAs heterostructural interface at sub-nanometer spatial resolution by thickness fringe imaging
Publisher: Elsevier BV
Date: 08-2002
Identification and modulation of electronic band structures of single-phase β-(Alx Ga1-x )2 O3 alloys grown by laser molecular beam epitaxy
Publisher: AIP Publishing
Date: 23-07-2018
DOI: 10.1063/1.5027763
Abstract: Understanding the band structure evolution of (AlxGa1−x)2O3 alloys is of fundamental importance for developing Ga2O3-based power electronic devices and vacuum ultraviolet super-radiation hard detectors. Here, we report on the bandgap engineering of β-(AlxGa1−x)2O3 thin films and the identification of compositionally dependent electronic band structures by a combination of absorption spectra analyses and density functional theory calculations. Single-monoclinic β-phase (AlxGa1−x)2O3 (0 ≤ x ≤ 0.54) films with a preferred (−201) orientation were grown by laser molecular beam epitaxy with tunable bandgap ranging from 4.5 to 5.5 eV. The excellent fitting of absorption spectra by the relation of (αhν)1/2 ∝ (hν-E) unambiguously identifies that β-(AlxGa1−x)2O3 alloys are indirect bandgap semiconductors. Theoretical calculations predict that the indirect nature of β-(AlxGa1−x)2O3 becomes more pronounced with increased Al composition due to the increased eigenvalue energy gap between M and Г points in the valence band. The experimentally determined indirect bandgap exhibits almost a linear relationship with Al composition, which is consistent with the theoretical calculation and indicates a small bowing effect and a good miscibility. The identification and modulation of (AlxGa1−x)2O3 band structures allows rational design of ultra-wide bandgap oxide heterostructures for the applications in power electronics and solar-blind or X-ray detection.
Strain hardening and softening in a nanocrystalline Ni-Fe alloy induced by severe plastic deformation
Publisher: Elsevier BV
Date: 04-2011
Phosphorus and transition metal co-segregation in ferritic iron grain boundaries and its effects on cohesion
Publisher: Elsevier BV
Date: 05-2023
Formation of a transition V-rich structure during the α' to α + β phase transformation process in additively manufactured Ti-6Al-4 V
Publisher: Elsevier BV
Date: 08-2022
Defects Engineering Induced Ultrahigh Magnetization in Rare Earth Element Nd‐doped MoS 2
Publisher: Wiley
Date: 17-12-2020
Introduction: Special Issue on Atom Probe Tomography
Publisher: Oxford University Press (OUP)
Date: 14-11-2007
DOI: 10.1017/S1431927607070912
Abstract: In February 2006, in conjunction with the 19th Australian Conference on Microscopy and Microanalysis held in Sydney, the 2nd Australian Workshop on Atom Probe Tomography was convened by S.P. Ringer, M.K. Miller, D.A. Saxey, and R. Zheng at the Australian Key Centre for Microscopy and Microanalysis at The University of Sydney. The topics covered at that workshop included specimen preparation data acquisition and data analysis methods for atom probe tomography applications to spinodal alloys, phase transformations, light metals, atomic clustering, and detection methods, as well as future directions of the science and technology of atom probe tomography. The presentations and discussions that took place at this workshop, which was attended by more than 30 people, provided the inspiration for this special issue of Microscopy and Microanalysis .
Radiation-enhanced fission track annealing revisited and consequences for apatite thermochronometry
Publisher: Wiley
Date: 26-07-2018
Radiation-enhanced fission track annealing revisited and consequences for apatite thermochronometry
Publisher: Wiley
Date: 26-02-2019
High strength and retained ductility achieved in a nitrided strip cast Nb-microalloyed steel
Publisher: Springer Science and Business Media LLC
Date: 02-10-2013
Radiation-enhanced fission track annealing revisited and consequences for apatite thermochronometry
Publisher: Wiley
Date: 16-07-2018
Self-Assembly of Gold Nanowires along Carbon Nanotubes for Ultrahigh-Aspect-Ratio Hybrids
Publisher: American Chemical Society (ACS)
Date: 04-05-2011
DOI: 10.1021/CM1033645
Isolated copper–tin atomic interfaces tuning electrocatalytic CO2 conversion
Publisher: Springer Science and Business Media LLC
Date: 04-03-2021
DOI: 10.1038/S41467-021-21750-Y
Abstract: Direct experimental observations of the interface structure can provide vital insights into heterogeneous catalysis. Ex les of interface design based on single atom and surface science are, however, extremely rare. Here, we report Cu–Sn single-atom surface alloys, where isolated Sn sites with high surface densities (up to 8%) are anchored on the Cu host, for efficient electrocatalytic CO 2 reduction. The unique geometric and electronic structure of the Cu–Sn surface alloys (Cu 97 Sn 3 and Cu 99 Sn 1 ) enables distinct catalytic selectivity from pure Cu 100 and Cu 70 Sn 30 bulk alloy. The Cu 97 Sn 3 catalyst achieves a CO Faradaic efficiency of 98% at a tiny overpotential of 30 mV in an alkaline flow cell, where a high CO current density of 100 mA cm −2 is obtained at an overpotential of 340 mV. Density functional theory simulation reveals that it is not only the elemental composition that dictates the electrocatalytic reactivity of Cu–Sn alloys the local coordination environment of atomically dispersed, isolated Cu–Sn bonding plays the most critical role.
Stabilized bismuth nanoplasmonics for selective CO2 reduction to methanol at a heterointerface
Publisher: Elsevier BV
Date: 10-2023
Selective Oxidation Synthesis of MnCr2O4 Spinel Nanowires from Commercial Stainless Steel Foil
Publisher: American Chemical Society (ACS)
Date: 18-10-2007
DOI: 10.1021/CG070514A
Microalloying effects of Mo versus Cr in HSLA steels with ultrafine-grained ferrite microstructures
Publisher: Elsevier BV
Date: 2020
Density-functional prediction of a surface magnetic phase in SrTiO3/LaAlO3 heterostructures induced by al vacancies
Publisher: American Physical Society (APS)
Date: 28-10-2014
Application of advanced analytical techniques to study structure-property relationship of hot rolled high strength low alloy steel
Publisher: Informa UK Limited
Date: 2011
Concurrent microstructural evolution of ferrite and austenite in a duplex stainless steel processed by high-pressure torsion
Publisher: Elsevier BV
Date: 2014
Creep Behavior of In-Situ Formed AlN Reinforced Mg-5Al Nanocomposite at Low Temperatures and Low Stresses
Publisher: American Scientific Publishers
Date: 12-2009
Lattice Rectification in Atom Probe Tomography: Toward True Three-Dimensional Atomic Microscopy
Publisher: Oxford University Press (OUP)
Date: 08-03-2011
DOI: 10.1017/S1431927610094535
Abstract: Atom probe tomography (APT) represents a significant step toward atomic resolution microscopy, analytically imaging in idual atoms with highly accurate, though imperfect, chemical identity and three-dimensional (3D) positional information. Here, a technique to retrieve crystallographic information from raw APT data and restore the lattice-specific atomic configuration of the original specimen is presented. This lattice rectification technique has been applied to a pure metal, W, and then to the analysis of a multicomponent Al alloy. Significantly, the atoms are located to their true lattice sites not by an averaging, but by triangulation of each particular atom detected in the 3D atom-by-atom reconstruction. Lattice rectification of raw APT reconstruction provides unprecedented detail as to the fundamental solute hierarchy of the solid solution. Atomic clustering has been recognized as important in affecting alloy behavior, such as for the Al-1.1Cu-1.7Mg (at. %) investigated here, which exhibits a remarkable rapid hardening reaction during the early stages of aging, linked to clustering of solutes. The technique has enabled lattice-site and species-specific radial distribution functions, nearest-neighbor analyses, and short-range order parameters, and we demonstrate a characterization of solute-clustering with unmatched sensitivity and precision.
Microscopy and microanalysis of complex nanosized strengthening precipitates in new generation commercial Al-Cu-Li alloys
Publisher: Wiley
Date: 03-06-2014
DOI: 10.1111/JMI.12143
Abstract: Precipitates (ppts) in new generation aluminum-lithium alloys (AA2099 and AA2199) were characterised using scanning and transmission electron microscopy and atom probe tomography. Results obtained on the following ppts are reported: Guinier-Preston zones, T1 (Al2 CuLi), β' (Al3 Zr) and δ' (Al3 Li). The focus was placed on their composition and the presence of minor elements. X-ray energy-dispersive spectrometry in the electron microscopes and mass spectrometry in the atom probe microscope showed that T1 ppts were enriched in zinc (Zn) and magnesium up to about 1.9 and 3.5 at.%, respectively. A concentration of 2.5 at.% Zn in the δ' ppts was also measured. Unlike Li and copper, Zn in the T1 ppts could not be detected using electron energy-loss spectroscopy in the transmission electron microscope because of its too low concentration and the small sizes of these ppts. Indeed, Monte Carlo simulations of EEL spectra for the Zn L2,3 edge showed that the signal-to-noise ratio was not high enough and that the detection limit was at least 2.5 at.%, depending on the probe current. Also, the simulation of X-ray spectra confirmed that the detection limit was exceeded for the Zn Kα X-ray line because the signal-to-noise ratio was high enough in that case, which is in agreement with our observations.
New approaches to nanoparticle sample fabrication for atom probe tomography
Publisher: Elsevier BV
Date: 12-2015
DOI: 10.1016/J.ULTRAMIC.2015.04.014
Abstract: Due to their unique properties, nano-sized materials such as nanoparticles and nanowires are receiving considerable attention. However, little data is available about their chemical makeup at the atomic scale, especially in three dimensions (3D). Atom probe tomography is able to answer many important questions about these materials if the challenge of producing a suitable s le can be overcome. In order to achieve this, the nanomaterial needs to be positioned within the end of a tip and fixed there so the s le possesses sufficient structural integrity for analysis. Here we provide a detailed description of various techniques that have been used to position nanoparticles on substrates for atom probe analysis. In some of the approaches, this is combined with deposition techniques to incorporate the particles into a solid matrix, and focused ion beam processing is then used to fabricate atom probe s les from this composite. Using these approaches, data has been achieved from 10-20 nm core-shell nanoparticles that were extracted directly from suspension (i.e. with no chemical modification) with a resolution of better than ± 1 nm.
Bistable Magnetism and Potential for Voltage-Induced Spin Crossover in Dilute Magnetic Ferroelectrics
Publisher: American Physical Society (APS)
Date: 17-06-2015
A New Approach to the Determination of Concentration Profiles in Atom Probe Tomography
Publisher: Oxford University Press (OUP)
Date: 03-02-2012
DOI: 10.1017/S1431927611012530
Abstract: Atom probe tomography (APT) provides three-dimensional analytical imaging of materials with near-atomic resolution using pulsed field evaporation. The processes of field evaporation can cause atoms to be placed at positions in the APT reconstruction that can deviate slightly from their original site in the material. Here, we describe and model one such process—that of preferential retention of solute atoms in multicomponent systems. Based on relative field evaporation probabilities, we calculate the point spread function for the solute atom distribution in the “ z ,” or in-depth direction, and use this to extract more accurate solute concentration profiles.
Positron lifetime evolution during room temperature ageing in Al‐Zn‐Mg‐(Cu)
Publisher: Wiley
Date: 11-2009
Atomic-Scale Tomography: A 2020 Vision
Publisher: Oxford University Press (OUP)
Date: 13-05-2013
DOI: 10.1017/S1431927613000494
Abstract: Atomic-scale tomography (AST) is defined and its place in microscopy is considered. Arguments are made that AST, as defined, would be the ultimate microscopy. The available pathways for achieving AST are examined and we conclude that atom probe tomography (APT) may be a viable basis for AST on its own and that APT in conjunction with transmission electron microscopy is a likely path as well. Some possible configurations of instrumentation for achieving AST are described. The concept of metaimages is introduced where data from multiple techniques are melded to create synergies in a multidimensional data structure. When coupled with integrated computational materials engineering, structure–properties microscopy is envisioned. The implications of AST for science and technology are explored.
A reproducible method for damage-free site-specific preparation of atom probe tips from interfaces
Publisher: Wiley
Date: 29-09-2011
DOI: 10.1002/JEMT.21081
Abstract: Atom probe tomography (APT) is a mass spectrometry method with atomic-scale spatial resolution that can be used for the investigation of a wide range of materials. The main limiting factor with respect to the type of problems that can be addressed is the small volume investigated and the randomness of common s le preparation methods. With existing site-specific specimen preparation methods it is still challenging to rapidly and reproducibly produce large numbers of successful s les from specifically selected grain boundaries or interfaces for systematic studies. A new method utilizing both focused ion beam (FIB) and transmission electron microscopy (TEM) is presented that can be used to reproducibly produce damage-free atom probe s les with features of interest at any desired orientation with an accuracy of better than 50 nm from s les that require very little prior preparation.
Misfit epitaxial strain manipulated transport properties in cubic In2O3 hetero-epilayers
Publisher: AIP Publishing
Date: 08-09-2020
DOI: 10.1063/5.0021344
Abstract: In this Letter, we report on the evolution of electronic properties governed by epitaxial misfit strain in cubic In2O3 epilayers grown on sapphire. At elevated growth temperature, the competition between the film/substrate lattice mismatch and the thermal expansion mismatch alters the macroscopic biaxial strain from compressive to tensile. Simultaneously, the electron concentration is tuned from degeneration to non-degeneration density below the Mott criterion. The observed surface electron accumulation and metal-insulator transition result from the oxygen deficiency formed at low growth temperature, while high-temperature epitaxy is favorable to achieve remarkably enhanced mobility. The effective strain-property coupling suggests that the improved oxygen stoichiometry and the Fermi level movement controlled by the biaxial strains are responsible for the Mott transition. The strain-mediated reduction of the electron effective mass contributes to the enhanced intrinsic mobility in tensile-strained In2O3 epilayers. These results highlight that strain engineering is an effective stimulus to manipulate the transport properties of oxide semiconductors with improved performance and unexpected functionalities.
A study of the composition dependence of the rapid hardening phenomenon in Al-Cu-Mg alloys using diffusion couples
Publisher: Elsevier BV
Date: 06-2012
Characterization of the bake-hardening behavior of transformation induced plasticity and dual-phase steels using advanced analytical techniques
Publisher: Iron and Steel Institute of Japan
Date: 2010
An inverse analysis approach based on a POD direct model for the mechanical characterization of metallic materials
Publisher: Elsevier BV
Date: 12-2014
Three-dimensional atom probe microscopy study of interphase precipitation and nanoclusters in thermomechanically treated titanium–molybdenum steels
Publisher: Elsevier BV
Date: 04-2013
Grain boundary formation by remnant dislocations from the de-twinning of thin nano-twins
Publisher: Elsevier BV
Date: 04-2015
Direct Observation of Dopants Distribution and Diffusion in GaAs Planar Nanowires with Atom Probe Tomography
Publisher: American Chemical Society (ACS)
Date: 27-09-2016
Abstract: Intentional and unintentional doping in semiconductor nanowires undoubtedly have significant impact on the device performance. However, spatially resolved precise determination of dopant concentration is challenging due to insufficient sensitivity and resolution of conventional techniques. In this paper, quantitative 3D distribution of Si and Zn dopants in planar GaAs nanowires and their interface with AlGaAs film underneath are obtained by using a unique atom probe tomography technique, providing critical insights for the growth and potential applications of these nanowires.
Growth of SAPO-34 in polymer hydrogels through vapor-phase transport
Publisher: Elsevier BV
Date: 11-2005
Microstructure-property gradients in Ni-based superalloy (Inconel 738) additively manufactured via electron beam powder bed fusion
Publisher: Elsevier BV
Date: 10-2021
Influence of surface migration on the spatial resolution of pulsed laser atom probe tomography
Publisher: AIP Publishing
Date: 15-08-2010
DOI: 10.1063/1.3462399
Abstract: The impact of laser pulsing on the field evaporation process is investigated for Al and W by pulsed laser atom probe tomography. Quantitative analysis reveals the influence on the spatial resolution of the peak temperature reached by the specimen following light absorption from the laser pulse. It is concluded that surface migration processes induce significant degradation of the lateral resolution, changing by 100% and 20%, respectively, for Al and W when the specimen temperature is increased from 4% to 7% of the material’s melting point, while the in-depth resolution is shown to remain nearly constant for both materials.
Assessment of temper embrittlement in an ex-service 1Cr–1Mo–0.25V power generating rotor by Charpy V-Notch testing, KIc fracture toughness and small punch test
Publisher: Elsevier BV
Date: 08-2002
Atom Probe Analysis of a Zr-based Bulk Metallic Glass
Publisher: Oxford University Press (OUP)
Date: 08-2022
DOI: 10.1017/S1431927621012824
Abstract: Zr-based bulk metallic glasses (BMGs) are amorphous alloys that can exhibit excellent mechanical properties, including high yield strength and fracture toughness. These properties are linked to local microstructural heterogeneities. Whether via microscopy-based techniques, synchrotron techniques, or calorimetric approaches, the amorphous structure of BMGs makes the characterisation of the details of these local structural and chemical heterogeneities extremely challenging. Our focus here is on atom probe tomography (APT), where considerable uncertainty remains in terms of how and when to apply this otherwise powerful technique to amorphous materials. This work reports a systematic evaluation of the experimental parameter space. We report results of BMG composition acquired against various APT operating parameters for Zr63.96Cu13.36Ni10.29Al11.04Nb1.25 (at. %). We demonstrate that a customised peak-based ranging approach yields satisfactory compositional accuracy with absolute errors of & at. %. Beyond composition, we have discussed the data quality in terms of attributes of the mass spectra: mass resolution, signal-to-thermal tail ratio, and overlapped peak ratio. We also assess the composition of the well-known clustered evaporation effects, common in APT data of BMGs. We conclude that these regions have negligible differences in composition from the surrounding “matrix” or bulk in these alloys.
Effect of deformation temperature on niobium clustering, precipitation and austenite recrystallisation in a Nb–Ti microalloyed steel
Publisher: Elsevier BV
Date: 10-2013
Response to comments on cluster hardening in an aged Al-Cu-Mg alloy
Publisher: Elsevier BV
Date: 11-1998
A quantitative atom probe study of the Nb excess at prior austenite grain boundaries in a Nb microalloyed strip-cast steel
Publisher: Elsevier BV
Date: 08-2012
Mechanism for strong magnetoelectric coupling in dilute magnetic ferroelectrics
Publisher: American Physical Society (APS)
Date: 16-11-2016
Non-destructive analysis on nano-textured surface of the vertical LED for light enhancement
Publisher: Elsevier BV
Date: 2019
DOI: 10.1016/J.ULTRAMIC.2018.09.003
Abstract: In this work, the nano-textured surface of a GaN-based vertical light emitting diode (VLED) is characterized using a unified framework of non-destructive techniques (NDT) incorporating scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy, Photoluminescence (PL), and X-ray diffraction (XRD) to optimize the light output efficiency. The surface roughness of ∼300 nm is revealed by AFM. Compressive stress-state of 0.667 GPa in the GaN surface is indicated by the E
Creep and Recovery Behaviour of Polyolefin-Rubber Nanocomposites Developed for Additive Manufacturing
Publisher: MDPI AG
Date: 15-12-2016
DOI: 10.3390/POLYM8120437
Segregation of solute elements at grain boundaries in an ultrafine grained Al-Zn-Mg-Cu alloy
Publisher: Elsevier BV
Date: 05-2011
Atom probe crystallography: Characterization of grain boundary orientation relationships in nanocrystalline aluminium
Publisher: Elsevier BV
Date: 05-2011
DOI: 10.1016/J.ULTRAMIC.2010.11.014
Abstract: Spatial Distribution Maps (SDM) in their various forms have previously been used to identify and characterize crystallographic structure within APT reconstructions. Importantly, it has been shown that such SDM analyses can also provide the crystallographic orientation of the specimen with respect to the direction of the detector in the original experiment. In this study, we investigate the application of SDMs to the analysis of APT reconstruction of a nanocrystalline Al film. We demonstrate that significant intra-granular crystallographic information is retained in the reconstruction, even in the x-y plane perpendicular to the direction of the detector. Further, the crystallographic orientation of the grains can be characterized highly accurately not only with respect to the bulk specimen but also their misorientation with respect to neighbouring grains.
Attraction of semiconductor nanowires: An in situ observation
Publisher: Elsevier BV
Date: 11-2013
Crystallographic structural analysis in atom probe microscopy via 3D Hough transformation
Publisher: Elsevier BV
Date: 05-2011
DOI: 10.1016/J.ULTRAMIC.2010.11.018
Abstract: Whereas the atom probe is regarded almost exclusively as a technique for 3D chemical microanalysis of solids with the highest chemical and spatial resolution, we demonstrate that the technique can be used for detailed crystallographic determinations. We present a new method for the quantitative determination of crystal structure (plane spacings and angles) using a Hough transformation of the reconstructed atom probe data. The resolving power is shown to be high enough to identify poorly established, discontinuous planes that are typical in semiconducting materials. We demonstrate the determination of crystal geometry around a grain boundary and the use of the technique for the optimisation of tomographic reconstruction. We propose that this method will enable automatic spatial analysis and, ultimately, automated tomographic reconstruction in atom probe microscopy.
Effects of Si addition on the microstructure evolution of Al–Cu–Mg alloys in the α + S + T phase field
Publisher: Informa UK Limited
Date: 11-2013
Characterization of nanocomposite filaments developed for additive manufacturing
Publisher: Author(s)
Date: 2016
DOI: 10.1063/1.4965574
The effects of processing and organoclay properties on the structure of poly(methyl methacrylate)–clay nanocomposites
Publisher: Elsevier BV
Date: 08-2006
Characterisation of nano-grains in MgB2 superconductors by transmission Kikuchi diffraction
Publisher: Elsevier BV
Date: 05-2015
Mechano-chemical synthesis and characterization of Ti (C, N)-powder from TiN-MWCNTs/graphite
Publisher: Informa UK Limited
Date: 14-07-2019
Growth of boehmite nanoribers by assembling nanoparticles with surfactant micelles
Publisher: American Chemical Society (ACS)
Date: 17-03-2004
DOI: 10.1021/JP049485U
Direct Observation of Local Potassium Variation and Its Correlation to Electronic Inhomogeneity in (Ba1-xKx)Fe2As2 Pnictide
Publisher: American Physical Society (APS)
Date: 15-06-2011
Strong and ductile titanium–oxygen–iron alloys by additive manufacturing
Publisher: Springer Science and Business Media LLC
Date: 31-05-2023
DOI: 10.1038/S41586-023-05952-6
Abstract: Titanium alloys are advanced lightweight materials, indispensable for many critical applications 1,2 . The mainstay of the titanium industry is the α–β titanium alloys, which are formulated through alloying additions that stabilize the α and β phases 3–5 . Our work focuses on harnessing two of the most powerful stabilizing elements and strengtheners for α–β titanium alloys, oxygen and iron 1–5 , which are readily abundant. However, the embrittling effect of oxygen 6,7 , described colloquially as ‘the kryptonite to titanium’ 8 , and the microsegregation of iron 9 have hindered their combination for the development of strong and ductile α–β titanium–oxygen–iron alloys. Here we integrate alloy design with additive manufacturing (AM) process design to demonstrate a series of titanium–oxygen–iron compositions that exhibit outstanding tensile properties. We explain the atomic-scale origins of these properties using various characterization techniques. The abundance of oxygen and iron and the process simplicity for net-shape or near-net-shape manufacturing by AM make these α–β titanium–oxygen–iron alloys attractive for a erse range of applications. Furthermore, they offer promise for industrial-scale use of off-grade sponge titanium or sponge titanium–oxygen–iron 10,11 , an industrial waste product at present. The economic and environmental potential to reduce the carbon footprint of the energy-intensive sponge titanium production 12 is substantial.
First principles study of 3d transition metal doped Cu3N
Publisher: Elsevier BV
Date: 09-2012
In Situ Formation of BN Nanotubes during Nitriding Reactions
Publisher: American Chemical Society (ACS)
Date: 09-2005
DOI: 10.1021/CM050966F
Atom probe specimen preparation methods for nanoparticles
Publisher: Elsevier BV
Date: 03-2022
DOI: 10.1016/J.ULTRAMIC.2021.113420
Abstract: Revealing the position of materials with chemical selectivity at atomic scale within functional nanoparticles is essential to understand and control their performance and cutting-edge atom probe tomography is a powerful tool to undertake this task. In this paper, we demonstrate three effective methods to prepare the needle-shaped specimens required for atom probe tomography measurements from nanoparticles of different sizes and provide ex les of how atom probe can be used to provide data that is critical to their functionality. S les measured include lithium-ion batteries (LIBs) cathode nanoparticles (300 - 500 nm), nickel-doped silicon dioxide (Ni@SiO
Influence of Low Level Ag Additions on Mg-Alloy AZ91
Publisher: Wiley
Date: 28-01-2013
Rare-earth doped boron nitride nanotubes
Publisher: Elsevier BV
Date: 2008
Characterization of kenaf fiber composites prepared with tributyl citrate plasticized cellulose acetate
Publisher: Elsevier BV
Date: 03-2015
Structural, optical and magnetic properties of Co-doped ZnO nanorods with hidden secondary phases
Publisher: IOP Publishing
Date: 25-03-2015
DOI: 10.1088/0957-4484/19/45/455702
Abstract: Co-doped ZnO nanorods (composition: Zn(0.955)Co(0.045)O) were grown by a simple surfactant-assisted hydrothermal technique. The morphological, structural, optical and magnetic properties of the as-prepared nanorods were investigated by means of scanning electron microscopy, high-resolution transmission electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy, micro-Raman spectroscopy, micro-cathodoluminescence, and vibrating s le magnetometry (VSM). The results showed that the s le had rod-like morphology and that the preferential growth direction was along the c axis. While Co was successfully doped into the ZnO wurtzite lattice structure as revealed by several characterization techniques, hidden secondary phases of Zn(y)Co(3-y)O(4) (0≤y≤1) were also clearly detected by the micro-Raman spectroscopic technique. We propose that the predominant diffusion-limited Ostwald ripening crystal growth mechanism under the hydrothermal coarsening yielded such phase segregation. VSM results showed that the nanorods displayed relatively weak room-temperature ferromagnetism. We suggest that the origin of the ferromagnetism is probably due to the presence of the mixed cation valence of Co via a d-d double-exchange mechanism rather than the real doping effect. It is essential to control the crystal growth mechanism and defect states associated with the ferromagnetism in order to realize the intrinsic diluted magnetic semiconductors.
Iron in solution with aluminum matrix after non-equilibrium processing: an atom probe tomography study
Publisher: Informa UK Limited
Date: 20-02-2017
Facilitation of Ferroelectric Switching via Mechanical Manipulation of Hierarchical Nanoscale Domain Structures
Publisher: American Physical Society (APS)
Date: 06-01-2017
An atom-probe tomography primer
Publisher: Springer Science and Business Media LLC
Date: 10-2009
DOI: 10.1557/MRS2009.194
Abstract: Atom-probe tomography (APT) is in the midst of a dynamic renaissance as a result of the development of well-engineered commercial instruments that are both robust and ergonomic and capable of collecting large data sets, hundreds of millions of atoms, in short time periods compared to their predecessor instruments. An APT setup involves a field-ion microscope coupled directly to a special time-of-flight (TOF) mass spectrometer that permits one to determine the mass-to-charge states of in idual field-evaporated ions plus their x -, y -, and z -coordinates in a specimen in direct space with subnanoscale resolution. The three-dimensional (3D) data sets acquired are analyzed using increasingly sophisticated software programs that utilize high-end workstations, which permit one to handle continuously increasing large data sets. APT has the unique ability to dissect a lattice, with subnanometer-scale spatial resolution, using either voltage or laser pulses, on an atom-by-atom and atomic plane-by-plane basis and to reconstruct it in 3D with the chemical identity of each detected atom identified by TOF mass spectrometry. Employing pico- or femtosecond laser pulses using visible (green or blue light) to ultraviolet light makes the analysis of metallic, semiconducting, ceramic, and organic materials practical to different degrees of success. The utilization of dual-beam focused ion-beam microscopy for the preparation of microtip specimens from multilayer and surface films, semiconductor devices, and for producing site-specific specimens greatly extends the capabilities of APT to a wider range of scientific and engineering problems than could previously be studied for a wide range of materials: metals, semiconductors, ceramics, biominerals, and organic materials.
Carbon nanotubes for biological and biomedical applications
Publisher: IOP Publishing
Date: 12-09-2007
Correlating Atom Probe Crystallographic Measurements with Transmission Kikuchi Diffraction Data
Publisher: Oxford University Press (OUP)
Date: 14-03-2017
DOI: 10.1017/S1431927616012605
Abstract: Correlative microscopy approaches offer synergistic solutions to many research problems. One such combination, that has been studied in limited detail, is the use of atom probe tomography (APT) and transmission Kikuchi diffraction (TKD) on the same tip specimen. By combining these two powerful microscopy techniques, the microstructure of important engineering alloys can be studied in greater detail. For the first time, the accuracy of crystallographic measurements made using APT will be independently verified using TKD. Experimental data from two atom probe tips, one a nanocrystalline Al–0.5Ag alloy specimen collected on a straight flight-path atom probe and the other a high purity Mo specimen collected on a reflectron-fitted instrument, will be compared. We find that the average minimum misorientation angle, calculated from calibrated atom probe reconstructions with two different pole combinations, deviate 0.7° and 1.4°, respectively, from the TKD results. The type of atom probe and experimental conditions appear to have some impact on this accuracy and the reconstruction and measurement procedures are likely to contribute further to degradation in angular resolution. The challenges and implications of this correlative approach will also be discussed.
First-principles investigation of intrinsic point defects in perovskite CsSnBr3
Publisher: American Physical Society (APS)
Date: 12-03-2021
On the early stages of precipitation during direct ageing of Alloy 718
Publisher: Elsevier BV
Date: 04-2020
3D characterization of microstructural evolution and variant selection in additively manufactured Ti-6Al-4 V
Publisher: Springer Science and Business Media LLC
Date: 14-06-2021
Correlating spatial, temporal and chemical information in atom probe data: new insights from multiple evaporation in microalloyed steels
Publisher: Informa UK Limited
Date: 05-2013
High-mass Star Formation through Filamentary Collapse and Clump-fed Accretion in G22
Publisher: American Astronomical Society
Date: 28-12-2017
Negative Poisson's ratio in 2D life-boat structured crystals
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C8NA00352A
Abstract: The auxetic behavior is strongly correlated to the bond stretch or rotation and a method to discover it is provided.
Precipitation microstructure and age-hardening response of an Mg-Gd-Nd-Zn-Zr alloy
Publisher: Elsevier BV
Date: 02-2012
Enhanced grain refinement of an Al-Mg-Si alloy by high-pressure torsion processing at 100°C
Publisher: Elsevier BV
Date: 08-2012
Precipitation of quasicrystal approximant phases in an Al-Mg-Cu-Ge alloy
Publisher: Informa UK Limited
Date: 02-2013
Atom Probe Tomography Analysis of Boron and/or Phosphorus Distribution in Doped Silicon Nanocrystals
Publisher: American Chemical Society (ACS)
Date: 02-08-2016
Flame synthesis of carbon nanostructures on ni-plated hardmetal substrates
Publisher: Springer Science and Business Media LLC
Date: 13-04-2011
Abstract: In this article, we demonstrate that carbon nanostructures could be synthesized on the Ni-plated YG6 (WC-6 wt% Co) hardmetal substrate by a simple ethanol diffusion flame method. The morphologies and microstructures of the Ni-plated layer and the carbon nanostructures were examined by various techniques including scanning electron microscopy, X-ray diffraction, and Raman spectroscopy. The growth mechanism of such carbon nanostructures is discussed. This work may provide a strategy to improve the performance of hardmetal products and thus to widen their potential applications.
Doping Process of 2D Materials Based on the Selective Migration of Dopants to the Interface of Liquid Metals
Publisher: Wiley
Date: 12-09-2021
Abstract: The introduction of trace impurities within the doping processes of semiconductors is still a technological challenge for the electronics industries. By taking advantage of the selective enrichment of liquid metal interfaces, and harvesting the doped metal oxide semiconductor layers, the complexity of the process can be mitigated and a high degree of control over the outcomes can be achieved. Here, a mechanism of natural filtering for the preparation of doped 2D semiconducting sheets based on the different migration tendencies of metallic elements in the bulk competing for enriching the interfaces is proposed. As a model, liquid metal alloys with different weight ratios of Sn and Bi in the bulk are employed for harvesting Bi 2 O 3 ‐doped SnO nanosheets. In this model, Sn shows a much stronger tendency than Bi to occupy surface sites of the Bi–Sn alloys, even at the very high concentrations of Bi in the bulk. This provides the opportunity for creating SnO 2D sheets with tightly controlled Bi 2 O 3 dopants. By way of ex le, it is demonstrated how such nanosheets could be made selective to both reducing and oxidizing environmental gases. The process demonstrated here offers significant opportunities for future synthesis and fabrication processes in the electronics industries.
Nearest neighbour diagnostic statistics on the accuracy of APT solute cluster characterisation
Publisher: Informa UK Limited
Date: 03-2013
Tomographic Reconstruction in Atom Probe Microscopy: Past, Present. . . Future?
Publisher: Oxford University Press (OUP)
Date: 07-2009
DOI: 10.1017/S1431927609092988
Abstract: Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009
Hydrogen‐Induced Nonradiative Recombination in All‐Inorganic CsPbI3 Perovskite Solar Cells
Publisher: Wiley
Date: 22-05-2022
Abstract: All‐inorganic halide perovskites have thus far exhibited better thermal stability but lower power conversion efficiency (PCE), compared with their organic–inorganic hybrid counterparts. The experimentally observed nonradiative recombination loss is commonly attributed to the prevalence of native deep defects, yet the exact microscopic origin remains elusive. Based on density functional theory calculations, it is demonstrated that hydrogen impurities may incorporate in the prototypical all‐inorganic perovskite CsPbI 3 with a high density and serve as a new source of efficient nonradiative recombination centers. The resultant nonradiative efficiency loss can be significantly higher than those induced by native deep defects, namely interstitials and antisites , contributing to the subdued performance of the CsPbI 3 ‐based devices. Furthermore, it is proposed that the iodine‐moderate growth conditions can effectively reduce the detrimental hydrogen ions. These results highlight the impact of unintentionally incorporated impurities and offer insights into the optimal synthetic route and practical operating protocols in the field of all‐inorganic perovskite solar cells.
Impact of laser pulsing on the reconstruction in an atom probe tomography
Publisher: Elsevier BV
Date: 08-2010
DOI: 10.1016/J.ULTRAMIC.2010.04.017
Abstract: The implementation of fast pulsed laser has significantly improved the performance of the atom probe technique by enabling near-atomic-scale three-dimensional analysis of poorly conducting materials. This has broadened the range of applications for the atom probe, addressing a major limitation of the technique. Despite this, the implications of lasing on the tomographic reconstruction of atom probe data have yet to be fully characterised. Here, we demonstrate how changes in the shape of the specimen surface, induced by laser pulsing, affect the ion trajectories, and hence the projection parameters used to build the three-dimensional map.
Electron tomography using a geometric surface-tangent algorithm: Application to atom probe specimen morphology
Publisher: AIP Publishing
Date: 15-05-2009
DOI: 10.1063/1.3129310
Abstract: To adapt electron tomography for the specific study of specimen morphology, a novel reconstruction algorithm is proposed which treats strong intensity gradients in images as arising from the projected edges of surfaces. Images portraying scattering interfaces arising from absorption, elastic, or Fresnel diffraction processes are used to identify edge maps that define the abscissa of projected surface tangents. Differential geometry is used to calculate the shape of these surfaces by considering smooth variations of measured tangent abscissa to infer local tangent intersections. The approach outlined here is not restricted to convex shapes and is designed for cases where morphology is more important than retrieval of the three-dimensional scattering density. The proposed algorithm is tested on simulated data, experimental benchmark specimens of MgO nanoparticles and is then applied to a nanosized atom probe tip, for which the approach here was specifically developed.
Advanced structural analysis of a laser additive manufactured Zr-based bulk metallic glass along the build height
Publisher: Springer Science and Business Media LLC
Date: 04-03-2022
DOI: 10.1007/S10853-022-06991-6
Abstract: Additive manufacturing of bulk metallic glasses (BMGs) has opened this material class to an exciting new range of potential applications, as bulk-scale, net-shaped amorphous components can be fabricated in a single step. However, there exists a critical need to understand the structural details of additive manufactured BMGs and how the glassy structure is linked to the mechanical properties. Here, we present a study of structure and property variations along the build height for a laser powder bed fusion (LPBF) processed Zr-based BMG with composition Zr 59.3 Cu 28.8 Nb 1.5 Al 10.4 commercially termed AMZ4, using hardness testing, calorimetry, positron annihilation spectroscopy, synchrotron X-ray diffraction, and transmission electron microscopy. A lower hardness, more rejuvenated glassy structure was found at the bottom of the build compared to the middle region of the build, with the structure and properties of the top region between the two. Such differences could not be attributed to variability in chemical composition or crystallisation rather, the softer bottom region was found to have a larger medium range order cluster size, attributed to heat dissipation into the build plate during processing, which gave faster cooling rates and less reheating compared to the steady-state middle of the build. However, at the top of the build less reheating occurs compared to the middle, leading to a somewhat softer and less relaxed state. Graphical abstract
The role of graphite addition on spark plasma sintered titanium nitride
Publisher: Elsevier BV
Date: 05-2020
Characterisation of an ultra-thin multilayer structure for spintronic materials
Publisher: IEEE
Date: 02-2010
The chemistry of precipitates in an aged Al-2.1Zn-1.7Mg at.% alloy
Publisher: Elsevier BV
Date: 10-1999
Grain size quantification by optical microscopy, electron backscatter diffraction, and magnetic force microscopy
Publisher: Elsevier BV
Date: 10-2017
DOI: 10.1016/J.MICRON.2017.06.001
Abstract: Quantification of microstructure, especially grain size, in polycrystalline materials is a vital aspect to understand the structure-property relationships in these materials. In this paper, representative characterization techniques for determining the grain size, including optical microscopy (OM), electron backscatter diffraction (EBSD) in the scanning electron microscopy (SEM), and atomic force microscopy/magnetic force microscopy (AFM/MFM), are thoroughly evaluated in comparison, illustrated by rare-earth sintered Nd-Fe-B permanent magnets. Potential applications and additional information achieved by using aforementioned characterization techniques have been discussed and summarized.
Influence of equal-channel angular pressing on precipitation in an Al-Zn-Mg-Cu alloy
Publisher: Elsevier BV
Date: 06-2009
Corrosion Behaviour of Al-4Mg-1Cu (wt%) Microalloyed with Si and Ag
Publisher: Wiley
Date: 08-06-2015
Optimization of pulsed laser atom probe (PLAP) for the analysis of nanocomposite Ti–Si–N films
Publisher: Elsevier BV
Date: 06-2010
DOI: 10.1016/J.ULTRAMIC.2010.03.003
Abstract: Laser-assisted atom probe tomography was used to investigate the nanostructure and composition of high-performance, ultra-hard Ti-Si-N nanocomposite films. However, the quality of data is heavily dependent on analysis conditions. In order to obtain reliable data from these, and other 'less conducting' specimens, the analysis parameter space was thoroughly investigated to optimize the mass resolution and hit multiplicity obtained in atom probe tomography. Geometric factors including tip radius and shank angle were found to play a significant role in mass resolution but had no apparent effect on the number of multiple hits observed. Increased laser energy led to a gradual increase in the number of single hits, but a modest improvement in mass resolution. The influence of other instrumental factors including detection rate and base temperature was investigated separately. Preliminary PLAP results are presented, and correlated with TEM analysis of the microstructure of the film.
Can misfit dislocations be located above the interface of InAs/GaAs (001) epitaxial quantum dots?
Publisher: Springer Science and Business Media LLC
Date: 31-08-2012
Abstract: InAs/GaAs(001) quantum dots grown by droplet epitaxy were investigated using electron microscopy. Misfit dislocations in relaxed InAs/GaAs(001) islands were found to be located approximately 2 nm above the crystalline s le surface, which provides an impression that the misfit dislocations did not form at the island/substrate interface. However, detailed microscopy data analysis indicates that the observation is in fact an artefact caused by the surface oxidation of the material that resulted in substrate surface moving down about 2 nm. As such, caution is needed in explaining the observed interfacial structure.
Nucleation of precipitates in aged Al-Cu-Mg-(Ag) alloys with high Cu:Mg ratios
Publisher: Elsevier BV
Date: 05-1996
Nanostructure of aluminium alloy 2024: Segregation, clustering and precipitation processes
Publisher: Elsevier BV
Date: 02-2011
Effect of sample orientation and initial microstructures on the dynamic recrystallization of a Magnesium alloy
Publisher: Elsevier BV
Date: 04-2017
Preparation of dense nanostructured titania ceramic using two step sintering
Publisher: Informa UK Limited
Date: 03-2010
Mechanism of room-temperature superplasticity in ultrafine-grained Al–Zn alloys
Publisher: Elsevier BV
Date: 03-2023
Quantitative analysis of Nb in solid solution in low carbon steels by atom probe tomography and inductively coupled plasma mass spectroscopy
Publisher: Elsevier BV
Date: 09-2021
Thermal-strain-induced enhancement of electromagnetic properties of SiC-MgB2 composites
Publisher: AIP Publishing
Date: 26-01-2009
DOI: 10.1063/1.3078396
Abstract: The effect of thermal strain caused by the different thermal expansion coefficients (α) of the MgB2 and SiC phases on the electromagnetic properties was studied for SiC–MgB2 composite, which was made by premixing SiC and B, followed by Mg diffusion and reaction. Thermal strain in the MgB2 phase was demonstrated with x-ray diffraction, Raman spectroscopy, and transmission electron microscopy. In contrast to the common practice of improving the critical current density Jc and the upper critical field Hc2 of MgB2 through chemical substitution, by taking advantage of residual thermal strains, we are able to design a composite showing only a small decrease in the critical temperature and a little increase in resistivity but a significant improvement over the Jc and Hc2 of pure MgB2.
Performance modulation of α-MnO 2 nanowires by crystal facet engineering
Publisher: Springer Science and Business Media LLC
Date: 11-03-2052
DOI: 10.1038/SREP08987
Abstract: Modulation of material physical and chemical properties through selective surface engineering is currently one of the most active research fields, aimed at optimizing functional performance for applications. The activity of exposed crystal planes determines the catalytic, sensory, photocatalytic and electrochemical behavior of a material. In the research on nanomagnets, it opens up new perspectives in the fields of nanoelectronics, spintronics and quantum computation. Herein, we demonstrate controllable magnetic modulation of α-MnO 2 nanowires, which displayed surface ferromagnetism or antiferromagnetism, depending on the exposed plane. First-principles density functional theory calculations confirm that both Mn- and O-terminated α-MnO 2 (1 1 0) surfaces exhibit ferromagnetic ordering. The investigation of surface-controlled magnetic particles will lead to significant progress in our fundamental understanding of functional aspects of magnetism on the nanoscale, facilitating rational design of nanomagnets. Moreover, we approved that the facet engineering pave the way on designing semiconductors possessing unique properties for novel energy applications, owing to that the bandgap and the electronic transport of the semiconductor can be tailored via exposed surface modulations.
Magic numbers of nanoholes in graphene: Tunable magnetism and semiconductivity
Publisher: American Physical Society (APS)
Date: 06-09-2011
Dislocation density evolution during high pressure torsion of a nanocrystalline Ni-Fe alloy
Publisher: AIP Publishing
Date: 02-03-2009
DOI: 10.1063/1.3095852
Abstract: High-pressure torsion (HPT) induced dislocation density evolution in a nanocrystalline Ni-20 wt %Fe alloy was investigated using x-ray diffraction and transmission electron microscopy. Results suggest that the dislocation density evolution is fundamentally different from that in coarse-grained materials. The HPT process initially reduces the dislocation density within nanocrystalline grains and produces a large number of dislocations located at small-angle subgrain boundaries that are formed via grain rotation and coalescence. Continuing the deformation process eliminates the subgrain boundaries but significantly increases the dislocation density in grains. This phenomenon provides an explanation of the mechanical behavior of some nanostructured materials.
Probing the Structure of Colloidal Core/Shell Quantum Dots Formed by Cation Exchange
Publisher: American Chemical Society (ACS)
Date: 03-02-2012
DOI: 10.1021/JP2112928
Electrode-induced impurities in tin halide perovskite solar cell material CsSnBr3 from first principles
Publisher: Springer Science and Business Media LLC
Date: 06-05-2021
DOI: 10.1038/S41524-021-00533-5
Abstract: All-inorganic lead-free CsSnBr 3 is attractive for applications in solar cells due to its nontoxicity and stability, but the device performance to date has been poor. Besides the intrinsic properties, impurities induced from electrodes may significantly influence the device performance. Here, we systematically studied the stability, transition energy levels, and diffusion of impurities from the most commonly used electrodes ( Au, Ag, Cu, graphite , and graphene ) in CsSnBr 3 based on density functional theory calculations. Our results reveal that, whereas graphite and graphene electrodes exhibit negligible influence on CsSnBr 3 due to the relatively high formation energies for carbon impurities in CsSnBr 3 , atoms from the metal electrodes can effectively diffuse into CsSnBr 3 along interstice and form electrically active impurities in CsSnBr 3 . In this case, a significant amount of donor interstitial impurities, such as $$Ag_i^ +$$ A g i + , $$Cu_i^ +$$ C u i + , and $$Au_i^ +$$ A u i + , will be formed under p -type conditions, whereas the Sn-site substitutional acceptor impurities, namely $$Au_{Sn}^{2 - }$$ A u S n 2 − , $$Ag_{Sn}^{2 - }$$ A g S n 2 − , and $$Cu_{Sn}^{2 - }$$ C u S n 2 − , are the dominant impurities, especially under n -type conditions. In particular, except for $$Au_i^ +$$ A u i + , all these major impurities from the metal electrodes act as nonradiative recombination centers in CsSnBr 3 and significantly degrade the device performance. Our work highlights the distinct behaviors of the electrode impurities in CsSnBr 3 and their influence on the related devices and provides valuable information for identifying suitable electrodes for optoelectronic applications.
Recent Advances in Atom Probe Tomography and Applications to Understanding Nanomaterials
Publisher: Oxford University Press (OUP)
Date: 31-07-2006
DOI: 10.1017/S1431927606068206
Abstract: Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2005
3D Atomic‐Scale Insights into Anisotropic Core–Shell‐Structured InGaAs Nanowires Grown by Metal–Organic Chemical Vapor Deposition
Publisher: Wiley
Date: 19-06-2017
Abstract: III–V ternary InGaAs nanowires have great potential for electronic and optoelectronic device applications however, the 3D structure and chemistry at the atomic‐scale inside the nanowires remain unclear, which hinders tailoring the nanowires for specific applications. Here, atom probe tomography is used in conjunction with a first‐principles simulation to investigate the 3D structure and chemistry of InGaAs nanowires, and reveals i) the nanowires form a spontaneous core–shell structure with a Ga‐enriched core and an In‐enriched shell, due to different growth mechanisms in the axial and lateral directions ii) the shape of the core evolves from hexagon into Reuleaux triangle and grows larger, which results from In outward and Ga inward interdiffusion occurring at the core–shell interface and iii) the irregular hexagonal shell manifests an anisotropic growth rate on {112}A and {112}B facets. Accordingly, a model in terms of the core–shell shape and chemistry evolution is proposed, which provides fresh insights into the growth of these nanowires.
Unusual macroscopic shearing patterns observed in metals processed by high-pressure torsion
Publisher: Springer Science and Business Media LLC
Date: 17-04-2010
Effect of Al and Gd Solutes on the Strain Rate Sensitivity of Magnesium Alloys
Publisher: Springer Science and Business Media LLC
Date: 05-01-2010
Colossal Magnetization and Giant Coercivity in Ion-Implanted (Nb and Co) MoS2 Crystals
Publisher: American Chemical Society (ACS)
Date: 16-12-2020
EDP2PDF: a computer program for extracting a pair distribution function from an electron diffraction pattern for the structural analysis of materials
Publisher: International Union of Crystallography (IUCr)
Date: 31-05-2023
DOI: 10.1107/S1600576723004053
Abstract: Pair distribution function (PDF) analysis is a powerful technique to understand atomic scale structure in materials science. Unlike X-ray diffraction (XRD)-based PDF analysis, the PDF calculated from electron diffraction patterns (EDPs) using transmission electron microscopy can provide structural information from specific locations with high spatial resolution. The present work describes a new software tool for both periodic and amorphous structures that addresses several practical challenges in calculating the PDF from EDPs. The key features of this program include accurate background subtraction using a nonlinear iterative peak-clipping algorithm and automatic conversion of various types of diffraction intensity profiles into a PDF without requiring external software. The present study also evaluates the effect of background subtraction and the elliptical distortion of EDPs on PDF profiles. The EDP2PDF software is offered as a reliable tool to analyse the atomic structure of crystalline and non-crystalline materials.
Atom Probe Microscopy
Publisher: Springer New York
Date: 2012
Thermo-analysis of nanocrystalline TiO2 ceramics during the whole sintering process using differential scanning calorimetry
Publisher: Elsevier BV
Date: 03-2010
Design of solute clustering during thermomechanical processing of AA6016 Al–Mg–Si alloy
Publisher: Elsevier BV
Date: 2021
The Benefit and Impact of On-Line Tools for Microscopy and Microanalysis Training and Education in Core Facilities.
Publisher: Oxford University Press (OUP)
Date: 08-2014
Insights into the Silver Reflection Layer of a Vertical LED for Light Emission Optimization
Publisher: American Chemical Society (ACS)
Date: 10-07-2017
Abstract: In this work, Ag as a highly reflective mirror layer of gallium nitride (GaN)-based blue vertical light-emitting diodes (VLEDs) has been systematically investigated by correlating scanning electron microscopy/energy dispersive X-ray spectroscopy/transmission Kikuchi diffraction/electron backscatter diffraction, aberration-corrected scanning transmission electron microscopy, and atomic force microscopy techniques. In the context of high-efficiency lighting, three critical aspects have been scrutinized on the nanoscale: (1) chemical diffusion, (2) grain morphology, and (3) surface topography of the Ag layer. We found that nanoscale inhomogeneous distribution of In in InGaN/GaN quantum wells (QWs), interfacial diffusion (In/Ga out-diffusion into the Ag layer and diffusion of Ag into p-GaN and QWs), and Ag agglomeration deteriorate the light reflectivity, which account for the decreased luminous efficiency in VLEDs. Meanwhile, the surface morphology and topographical analyses revealed the nanomorphology of the Ag layer, where a nanograin size of ∼300 nm with special nanotwinned boundaries and an extremely smooth surface of ∼3-4 nm are strongly desired for better reflectivity. Further, on the basis of these microscopy results, suggestions on light extraction optimization are given to improve the performance of GaN-based blue VLEDs. Our findings enable fresh and deep understanding of performance-microstructure correlation of LEDs on the nanoscale, providing guidance to the design and manufacture of high-performance LED devices.
Hydrogen-induced decomposition of Zr-rich cores in an Mg−6Zn−0.6Zr−0.5Cu alloy
Publisher: Elsevier BV
Date: 09-2012
Enhancement of transition temperature in FexSe0.5Te0.5 film via iron vacancies
Publisher: AIP Publishing
Date: 30-06-2014
DOI: 10.1063/1.4886995
Abstract: The effects of iron deficiency in FexSe0.5Te0.5 thin films (0.8 ≤ x ≤ 1) on superconductivity and electronic properties have been studied. A significant enhancement of the superconducting transition temperature (TC) up to 21 K was observed in the most Fe deficient film (x = 0.8). Based on the observed and simulated structural variation results, there is a high possibility that Fe vacancies can be formed in the FexSe0.5Te0.5 films. The enhancement of TC shows a strong relationship with the lattice strain effect induced by Fe vacancies. Importantly, the presence of Fe vacancies alters the charge carrier population by introducing electron charge carriers, with the Fe deficient film showing more metallic behavior than the defect-free film. Our study provides a means to enhance the superconductivity and tune the charge carriers via Fe vacancy, with no reliance on chemical doping.
Realization of High Magnetization in Artificially Designed Ni/NiO Layers through Exchange Coupling
Publisher: Wiley
Date: 15-09-2023
Porous ZnO nanonetworks grown by molecular beam epitaxy
Publisher: IOP Publishing
Date: 12-03-2012
DOI: 10.1088/0022-3727/45/13/135301
Abstract: Plasma-assisted molecular beam epitaxy was employed to create porous nanonetworks of ZnO directly on GaN epilayers without the use of catalysts or templates. Detailed analysis of scanning electron microscopy (SEM) images of both as-grown and etched s les reveals that the typical porous nanonetwork structure is multilayered, and suggests that dislocations originating at the GaN/sapphire heterointerface and/or defects characterizing an unusually rough GaN surface are responsible. The pore size distribution of the nanonetwork was measured using nuclear magnetic resonance (NMR) cryoporometry. A bimodal pore size distribution centred at 4 nm and 70 nm, respectively, was observed, consistent with the existence of small nanoscale pores in the bulk of the s le, and large open pores on the surface of the porous nanonetwork as observed by SEM.
Microstructural evolution and age hardening in aluminium alloys: atom probe field-ion microscopy and transmission electron microscopy studies
Publisher: Elsevier BV
Date: 2000
Giant room temperature compression and bending in ferroelectric oxide pillars
Publisher: Springer Science and Business Media LLC
Date: 17-01-2022
DOI: 10.1038/S41467-022-27952-2
Abstract: Plastic deformation in ceramic materials is normally only observed in nanometre-sized s les. However, we have observed high levels of plasticity ( % plastic strain) and excellent elasticity (6% elastic strain) in perovskite oxide Pb(In 1/2 Nb 1/2 )O 3 -Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 , under compression along pc pillars up to 2.1 μm in diameter. The extent of this deformation is much higher than has previously been reported for ceramic materials, and the s le size at which plasticity is observed is almost an order of magnitude larger. Bending tests also revealed over 8% flexural strain. Plastic deformation occurred by slip along {110} $$\\bar{1}$$ 1 ¯ 0 . Calculations indicate that the resulting strain gradients will give rise to giant flexoelectric polarization. First principles models predict that a high concentration of oxygen vacancies weaken the covalent/ionic bonds, giving rise to the unexpected plasticity. Mechanical testing on oxygen vacancies-rich Mn-doped Pb(In 1/2 Nb 1/2 )O 3 -Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 confirmed this prediction. These findings will facilitate the design of plastic ceramic materials and the development of flexoelectric-based nano-electromechanical systems.
Compositional variations in equiatomic CrMnFeCoNi high-entropy alloys
Publisher: Elsevier BV
Date: 10-2021
The mechanism for the enhanced piezoelectricity in multi-elements doped (K,Na)NbO3 ceramics
Publisher: Springer Science and Business Media LLC
Date: 09-02-2021
DOI: 10.1038/S41467-021-21202-7
Abstract: (K,Na)NbO 3 based ceramics are considered to be one of the most promising lead-free ferroelectrics replacing Pb(Zr,Ti)O 3 . Despite extensive studies over the last two decades, the mechanism for the enhanced piezoelectricity in multi-elements doped (K,Na)NbO 3 ceramics has not been fully understood. Here, we combine temperature-dependent synchrotron x-ray diffraction and property measurements, atomic-scale scanning transmission electron microscopy, and first-principle and phase-field calculations to establish the dopant–structure–property relationship for multi-elements doped (K,Na)NbO 3 ceramics. Our results indicate that the dopants induced tetragonal phase and the accompanying high-density nanoscale heterostructures with low-angle polar vectors are responsible for the high dielectric and piezoelectric properties. This work explains the mechanism of the high piezoelectricity recently achieved in (K,Na)NbO 3 ceramics and provides guidance for the design of high-performance ferroelectric ceramics, which is expected to benefit numerous functional materials.
On the interplay of internal voids, mechanical properties, and residual stresses in additively manufactured Haynes 282
Publisher: Elsevier BV
Date: 08-2023
Related Organisations
Kungliga Tekniska Högskolan Skolan För Teknikvetenskap
Location: Sweden
Australian Microscopy And Microanalysis Research Facility
Location: Australia
Australian Centre For Microscopy And Microanalysis, University Of Sydney
Location: Australia
Australian Centre For Microscopy And Microanalysis, University Of Sydney
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Locking Up Oxygen In Titanium To Achieve Strength-ductility Synergy
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Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE190100032
Start Date: 2019
End Date: 02-2021
Amount: $346,500.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP110100231
Start Date: 10-2011
End Date: 12-2016
Amount: $390,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP0453538
Start Date: 07-2004
End Date: 07-2009
Amount: $620,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP0775153
Start Date: 08-2007
End Date: 12-2011
Amount: $440,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP190100850
Start Date: 04-2021
End Date: 04-2024
Amount: $714,296.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE170100140
Start Date: 2017
End Date: 12-2018
Amount: $1,050,000.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP0452166
Start Date: 02-2004
End Date: 01-2008
Amount: $294,000.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP0452829
Start Date: 06-2004
End Date: 06-2009
Amount: $770,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE0239650
Start Date: 2001
End Date: 12-2002
Amount: $500,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP0348891
Start Date: 04-2004
End Date: 03-2008
Amount: $299,614.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP190101169
Start Date: 04-2021
End Date: 03-2024
Amount: $570,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE220100182
Start Date: 11-2022
End Date: 12-2023
Amount: $851,607.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP160101713
Start Date: 04-2016
End Date: 12-2020
Amount: $630,000.00
Funder: Australian Research Council
View Funded ActivitySpecial Research Initiatives - Grant ID: SR0354721
Start Date: 02-2004
End Date: 03-2004
Amount: $10,000.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP180101393
Start Date: 2018
End Date: 12-2021
Amount: $464,389.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP210301261
Start Date: 02-2024
End Date: 02-2027
Amount: $442,371.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP200100940
Start Date: 04-2021
End Date: 09-2024
Amount: $390,000.00
Funder: Australian Research Council
View Funded ActivitySpecial Research Initiatives - Grant ID: SR0567334
Start Date: 11-2005
End Date: 01-2008
Amount: $125,748.00
Funder: Australian Research Council
View Funded ActivityResearch Networks - Grant ID: RN0458455
Start Date: 07-2004
End Date: 06-2009
Amount: $1,500,000.00
Funder: Australian Research Council
View Funded ActivitySpecial Research Initiatives - Grant ID: SR0354722
Start Date: 02-2004
End Date: 12-2004
Amount: $20,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE0775598
Start Date: 10-2008
End Date: 11-2008
Amount: $1,000,000.00
Funder: Australian Research Council
View Funded ActivitySpecial Research Initiatives - Grant ID: SR0354832
Start Date: 02-2004
End Date: 11-2004
Amount: $10,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE120100035
Start Date: 08-2012
End Date: 12-2015
Amount: $200,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE0560680
Start Date: 08-2005
End Date: 11-2006
Amount: $901,862.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE210100025
Start Date: 04-2021
End Date: 04-2023
Amount: $468,000.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP150100018
Start Date: 2015
End Date: 12-2018
Amount: $473,900.00
Funder: Australian Research Council
View Funded ActivityResearch Networks - Grant ID: RN0460256
Start Date: 02-2005
End Date: 02-2010
Amount: $1,500,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE100100081
Start Date: 08-2010
End Date: 12-2010
Amount: $600,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE100100030
Start Date: 06-2011
End Date: 09-2011
Amount: $1,200,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE0883030
Start Date: 09-2008
End Date: 01-2011
Amount: $450,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE0989859
Start Date: 06-2009
End Date: 12-2010
Amount: $1,000,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE190100048
Start Date: 2019
End Date: 06-2021
Amount: $540,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE210100057
Start Date: 2021
End Date: 10-2022
Amount: $650,000.00
Funder: Australian Research Council
View Funded ActivityARC Centres Of Excellence - Grant ID: CE0561574
Start Date: 07-2005
End Date: 12-2014
Amount: $22,550,000.00
Funder: Australian Research Council
View Funded ActivitySpecial Research Initiatives - Grant ID: SR0354521
Start Date: 01-2004
End Date: 03-2005
Amount: $10,000.00
Funder: Australian Research Council
View Funded ActivitySpecial Research Initiatives - Grant ID: SR0354821
Start Date: 12-2003
End Date: 12-2004
Amount: $30,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE130100165
Start Date: 2013
End Date: 12-2015
Amount: $390,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE120100036
Start Date: 05-2012
End Date: 05-2013
Amount: $440,000.00
Funder: Australian Research Council
View Funded ActivityResearch Networks - Grant ID: RN0459611
Start Date: 07-2004
End Date: 12-2010
Amount: $1,900,000.00
Funder: Australian Research Council
View Funded Activity