ORCID Profile
0000-0003-2635-6921
Current Organisation
Australian Nuclear Science and Technology Organisation
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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.
Manufacturing Processes and Technologies (excl. Textiles) | Nanomaterials | Manufacturing Engineering | Condensed Matter Physics | Solid Mechanics | Mechanical Engineering | Metals and Alloy Materials | Electronic and Magnetic Properties of Condensed Matter; Superconductivity | Condensed Matter Imaging | Nuclear Physics |
Expanding Knowledge in Engineering | Nuclear Energy | Energy Transmission and Distribution (excl. Hydrogen) | Education and Training Systems not elsewhere classified | Energy Storage (excl. Hydrogen) | Expanding Knowledge in the Physical Sciences | Coated Metal and Metal-Coated Products
Publisher: Elsevier BV
Date: 04-2020
Publisher: MDPI AG
Date: 25-05-2021
DOI: 10.3390/MET11060861
Abstract: With the improvement in technology, additive manufacturing using metal powder has been a go-to method to produce complex-shaped components. With complex shapes being printed, the residual stresses (RS) developed during the printing process are much more difficult to control and manage, which is one of the issues seen in the field of AM. A simplified finite element-based, layer-by-layer activation approach for the prediction of residual stress is presented and applied to L-shaped s les built in two different orientations. The model was validated with residual stress distributions measured using neutron diffraction. It has been demonstrated that this simplified model can predict the trend of the residual stress distribution well inside the parts and give insight into residual stress evolution during printing with time for any area of interest. Although the stress levels predicted are higher than the measured ones, the impact of build direction on the development of RS during the building process and the final RS distributions after removing the base plate could be exploited using the model. This is important for finalizing the print orientation for a complex geometry, as the stress distribution will be different for different print orientations. This simplified tool which does not need high computational power and time can also be useful in component design to reduce the residual stresses.
Publisher: Trans Tech Publications, Ltd.
Date: 11-2013
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.772.155
Abstract: Cold spray technology is used to produce metal coatings with a variety of functions, including surface corrosion protection, improvement of wear resistance, etc. Cold sprayed materials exhibit a wide range of behaviours resulting in large variation of spraying efficiency, coating properties, quality and performance in service. Residual stress, being a result and attribute of the deposition process, can be studied to test whether the coating is in tension/compression stress state and also to provide information about the thermo-mechanical history of the material during the deposition process. Residual stress distributions in a variety of coating materials have been studied by neutron diffraction. Through-thickness residual stress profiles show that the stress magnitude varies significantly and depends mainly on the mechanical properties of the coating material.
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0NR01728K
Abstract: The relationship between nanoparticle morphology, self-induced atomic/magnetic texture and magnetic properties of high-performance hexaferrite magnets is elucidated using neutron/X-ray pole figure analysis and neutron/synchrotron powder diffraction.
Publisher: Elsevier BV
Date: 02-2021
Publisher: Elsevier BV
Date: 02-2022
Publisher: Elsevier BV
Date: 04-2014
Publisher: Trans Tech Publications, Ltd.
Date: 02-2014
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.777.19
Abstract: There are two major types of solid state phase transformations in metallic materials the formation of second phase particles during heat treatments, and the transformation of the matrix from one crystalline packing arrangement to another during either heating or cooling. These transformations change the spacing between adjacent atoms and can thus influence the residual stress levels formed. The heating and cooling cycles of materials processing operations using lasers such as cladding and melting/heating, can induce phase transformations depending on the character of the material being processed. This paper compares the effects of the different phase transformations and also the influence of the type of laser processing on the final residual stress formed. The comparisons are made between laser clad AA7075, laser clad Ti-6Al-4V and laser melted nickel-aluminium bronze using neutron diffraction and the contour method of measuring residual stress.
Publisher: Trans Tech Publications, Ltd.
Date: 08-2014
DOI: 10.4028/WWW.SCIENTIFIC.NET/AMR.996.969
Abstract: Three natural polycrystalline diamond s les have been investigated non-destructively in their raw as-discovered forms. The s les originate from different locations in the world and possibly have different mechanisms of formation. The study reveals that the stones are primarily composed of cubic diamond with varying amounts of impurities that emanate from their excessive porosities and entrapped environmental contamination from the areas they were formed and subsequently discovered. Residual stress analyses with X-ray and neutron diffraction techniques of the diamond phase in the interior regions of the diamonds revealed low stress values.
Publisher: Elsevier BV
Date: 12-2019
Publisher: Trans Tech Publications, Ltd.
Date: 04-2008
DOI: 10.4028/WWW.SCIENTIFIC.NET/AMR.41-42.439
Abstract: The Australian Nuclear Science and Technology Organisation (ANSTO) has recently started commissioning the new Australian Research Reactor OPAL that has replaced the old HIFAR reactor in January 2007. At the first stage, the new reactor will provide neutrons to several neutron scattering instruments. Among them is the residual stress diffractometer Kowari that was designed to study engineering problems related to residual stresses as well as allow material science research using neutron diffraction. We give an update on the progress of the instrument’s installation and commissioning and present an ex le to illustrate how neutron diffraction can be used to obtain information about residual stresses in a flash butt welded plate.
Publisher: Informa UK Limited
Date: 15-06-2022
Publisher: International Union of Crystallography (IUCr)
Date: 30-06-2023
DOI: 10.1107/S1600576723004855
Abstract: Although layer-based additive manufacturing methods such as laser powder bed fusion (PBF-LB) offer an immense geometrical freedom in design, they are typically subject to a build-up of internal stress ( i.e. thermal stress) during manufacturing. As a consequence, significant residual stress (RS) is retained in the final part as a footprint of these internal stresses. Furthermore, localized melting and solidification inherently induce columnar-type grain growth accompanied by crystallographic texture. Although diffraction-based methods are commonly used to determine the RS distribution in PBF-LB parts, such features pose metrological challenges in their application. In theory, preferred grain orientation invalidates the hypothesis of isotropic material behavior underlying the common methods to determine RS. In this work, more refined methods are employed to determine RS in PBF-LB/M/IN718 prisms, based on crystallographic texture data. In fact, the employment of direction-dependent elastic constants ( i.e. stress factors) for the calculation of RS results in insignificant differences from conventional approaches based on the hypothesis of isotropic mechanical properties. It can be concluded that this result is directly linked to the fact that the {311} lattice planes typically used for RS analysis in nickel-based alloys have high multiplicity and less strong texture intensities compared with other lattice planes. It is also found that the length of the laser scan vectors determines the surface RS distribution in prisms prior to their removal from the baseplate. On removal from the baseplate the surface RS considerably relaxes and/or redistributes a combination of the geometry and the scanning strategy dictates the sub-surface RS distribution.
Publisher: Geological Society of America
Date: 20-12-2018
DOI: 10.1130/G39584.1
Publisher: Elsevier BV
Date: 04-2016
Publisher: ASMEDC
Date: 2004
Abstract: Rail sectioning with subsequent neutron diffraction experiments has been used to assess residual stresses in the rails. In this study we present the results of neutron stress measurements performed at the NIST Center for Neutron Research (NCNR) on rail sections from rails that were produced under various conditions. Specifically, these are air-cooled, air-cooled and roller-straightened, head-hardened and head-hardened and roller-straightened. More significantly, a head-hardened and roller-straightened rail was also studied after service to elucidate evolution of the service-induced residual stresses. In the latter case both a transverse-cut slice and the central region of a 0.53 m long piece were studied. Measurements on this piece are the first in which triaxial stresses have been determined for an intact rail. Neutron strain measurements with 3×3×3 mm3 spatial resolution were successfully employed for transversally cut slices to verify the difference in the stress state depending on the production process. Although examination of slices allows determination of only two-dimensional stresses in the plane of the slice, additional measurements on obliquely-cut slices, which were also carried out, and utilization of FEM gives the possibility of reconstructing the full triaxial stress distribution. Together, these approaches provide a better understanding of rail fabrication and the possibility of improving the durability and safety of rails in the future.
Publisher: Trans Tech Publications, Ltd.
Date: 09-2013
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.768-769.193
Abstract: Problems of residual stress analysis can be formulated in terms of so-called eigenstrain or inelastic strain. Although the concept is almost 100 year old, the use of it by the residual stress community is quite limited, due to complexities of the associated mathematics. When mathematical difficulties are resolved and eigenstrain is reconstructed, the use of it can be beneficial in several ways. Firstly, the eigenstrain is essentially a generator function for residual elastic stress and elastic strain and it can be used, for generation of any stress field in FE models. Furthermore, eigenstrain distributions are frequently localized, even though the elastic stress or strain distributions are not. Both these properties can be used for effective data reduction. Another advantage of the use of the eigenstrain concept is that experimental data may be interpreted in a more meaningful way by using a narrower context, in terms of plastic deformation, thermal expansion/misfit and deformation caused by phase transformation, rather than just residual stress/strain field. The s le geometry and symmetry play an important role in resolving eigenstrain distributions from residual stress and elastic strain fields. Generally the equations are difficult to solve, however for a s le geometry of high symmetry, eigenstrain can be resolved and expressed as a solution of a relatively simple integral equation which is the Fredholm of the second type with the kernel of the integral operator defined by the s le geometry/symmetry. Several such symmetries are investigated, yielding analytical solutions that are applied and contrasted to experimental data. An important issue for residual stress analysis is the uniqueness of the solution is also discussed.
Publisher: Elsevier BV
Date: 08-2014
Publisher: Elsevier BV
Date: 08-2022
Publisher: Trans Tech Publications, Ltd.
Date: 11-2013
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.772.161
Abstract: Investigations of interaction residual stresses between thin WC-Co surface coated layers on thick mild steel substrates have successfully been performed with neutron diffraction. This systematic approach was conducted on the reference grit-blasted substrates and their HVOF coated WC-Co products. Using a sub-millimeter gauge volume, precisely positioned, the stress gradient through the coated and non-coated substrates were determined and used to derive the coating stress condition prevailing in the thin coating by applying the stress balance (Stoney) approach. In addition, the average stress in each 200 μm thick coating was measured directly with very good agreement obtained between the calculated and measured stress values. Investigations were extended to determine the thermal nature of the residual stresses by studying the annealed counterpart s les as well to follow the evolution of the residual stress upon annealing.
Publisher: Elsevier BV
Date: 05-2012
Publisher: Trans Tech Publications, Ltd.
Date: 02-2014
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.777.148
Abstract: Stone physical weathering, deterioration and damage (e.g. bowing, cracking, microfracturing) represent a serious problem for preservation of sculptural and architectural heritage objects. Although different mechanisms of such degradation might be responsible (e.g. chemical or biogenic), there is an understanding in the geological community that physical reasons for stone degradation and role of stress are of primary importance. In this work Carrara marble was a chosen for investigation: a calcitic type with ~20% of dolomite. Neutron diffraction was used to investigate the phase composition, the texture, and the strain/stress in calcite and dolomite phases in a bulk marble s le. Evolution of the stress state was studied by measuring strains in calcite and dolomite at two temperatures with clear evidence of thermally induced microstresses. Results are discussed in connection to the theory of composite materials and a micro-mechanical explanation of the general problem of marble deterioration is suggested.
Publisher: Elsevier BV
Date: 12-2016
Publisher: Trans Tech Publications, Ltd.
Date: 05-2010
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.652.50
Abstract: A range of different spraying techniques can be used to coat the surfaces of engineering components. These techniques are based on different principles and can involve high temperature (plasma spray), high kinetic energy (cold spray) or both (HVOF spray – High-Velocity Oxi-Fuel). Resultant residual stress in such coatings, being a characteristic of the spraying process, can reveal details of the stress formation mechanism. When its dependence on the physical parameters and conditions of the spraying process is established, this knowledge can be used for the prediction and control of stress that occurs in applications. Neutron diffraction is a suitable method for obtaining stress distribution in such coatings. Residual stresses in two-phase Cu+W coatings made by water stabilized plasma spraying were studied. Two-phase coatings develop both significant microstress (inter-phase stress) and the stress dependence on phase content of the coating constituents. Through-thickness residual stress profiles have been measured by neutron diffraction with spatial resolution of 0.5 mm for a series of Cu+W coatings with varying volume fractions. Measurements were made in both phases in order to separate micro- and macro-stresses. Comprehensive s le characterization, measurements of the residual stresses, mechanical and thermal properties of the composite coatings enabled quantitative modeling and interpretation of the experimental data.
Publisher: Trans Tech Publications, Ltd.
Date: 02-1998
Publisher: Springer Science and Business Media LLC
Date: 25-05-2020
DOI: 10.1007/S11666-020-01040-7
Abstract: Cold-spray additive manufacturing (CSAM) builds strong, dense metal parts from powder feedstock without melting and offers potential advantages over alternatives such as casting, liquid phase sintering, laser or e-beam melting or welding. Considerable effort is required to relieve residual stresses that arise from melt/freeze cycling in these methods. While CSAM does not involve melting, it imposes high strain rates on the feedstock and stress anisotropies due to complex build paths. This project explores residual stress in two CSAM objects. The CSAM components were produced from 99% pure copper powder (D50 = 17 µm): (1) a cylinder ( ∅ = 15 mm, height = 100 mm, weight = 145 g) and (2) a funnel (upper outer ∅ = 60 mm, lower outer ∅ = 40 mm, wall thickness = 8 mm, weight = 547 g). The non-heat-treated components were strain-scanned using a residual stress neutron diffractometer. Maximum residual stresses in any direction were: tensile: 103 ± 16 MPa (cylinder) and 100 ± 23 MPa (funnel) compression: 58 ± 16 MPa (cylinder) and 123 ± 23 MPa (funnel). Compared to the literature, the tensile residual stresses measured in the CSAM components were lower than those measured in cast materials, laser or welding AM methods, and numerical modelling of cold-spray coatings, while within the wide range reported for measurements in cold-spray coatings. These comparatively low residual stresses suggest CSAM is a promising manufacturing method where high residual stresses are undesirable.
Publisher: Trans Tech Publications, Ltd.
Date: 08-2017
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.905.190
Abstract: Granular materials demonstrate unique mechanical properties stemming from their discrete nature. At large length scales granular assemblies are often viewed from the perspective of continuum theory where they show complex behaviour such as elastic and plastic anisotropy related to the load and deformation history. This complex behaviour is inextricably linked to the micromechanics of load sharing and force transmission at the particle level. At these scales, bulk stress is not shared homogeneously between particles, but rather by a network of `force chains' that form a skeleton supporting the vast majority of the applied load. The formation and failure of these structures govern much of the bulk behaviour of these materials. Neutron diffraction techniques are now providing a window into the mechanics of granular materials at both bulk and particle scales. Through a combination of tomographic neutron imaging and diffraction based strain measurement it is now possible to directly examine the stress within in idual particles in granular assemblies. Results of these experiments in two and three dimensions are presented and the outlook for this approach to studying the mechanics of granular materials is discussed.
Publisher: AIP
Date: 2013
DOI: 10.1063/1.4811962
Publisher: Elsevier BV
Date: 08-2012
Publisher: Geological Society of America
Date: 03-04-2018
DOI: 10.1130/B31797.1
Publisher: Elsevier BV
Date: 10-2017
Publisher: Elsevier BV
Date: 02-2020
Publisher: Elsevier BV
Date: 09-2016
Publisher: Trans Tech Publications, Ltd.
Date: 03-2020
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.983.15
Abstract: A synergic combination of neutron techniques was applied to characterize non-invasively the laminated structure of a set of ancient katana, part of the East Asian Collection of the Museum of Applied Arts and Sciences (MAAS) in Sydney. Neutron tomography, diffraction, residual stress and Bragg-edge transmission analyses were undertaken on s les of well-known origin, time period and authorship to create a reference database on the main manufacturing methods developed by Japanese swordsmiths. In the attempt to attribute mumei (no-signature) blades basing on a scientific analytical method rather than a stylistic analysis, data from the reference s les were benchmarked against the results obtained from the unknown blade to identify differences and commonalities in the production process.
Publisher: Springer International Publishing
Date: 2020
Publisher: Trans Tech Publications, Ltd.
Date: 03-2008
Publisher: Trans Tech Publications, Ltd.
Date: 08-2011
DOI: 10.4028/WWW.SCIENTIFIC.NET/AMR.325.339
Abstract: Variability in the abrasive wear of PCD coatings on cemented WC substrates has been investigated. Six s les of PCD coated carbides were tested in a wear testing rig. The PCD coated element was used to turn an industry standard vitrified bonded corundum grinding wheel. The wear rate was measured as the weight loss of the cutting element per cubic metre of grinding wheel machined during the test. Two grades of cutting elements were observed. One grade had wear rates between 6 and 7.3 g/m³ but of the three poor quality s les, only one valid test was made realising wear rate of ~7,800 g/m³. The microstructures of the s les were studied using SEM, X-ray imaging, neutron diffraction and XRD. SEM images revealed differences in the volume percentage of diamonds in the two grades and the XRD scans highlighted the variable distribution of the diamond phase in the coating. Estimates of the residual stresses in a good and poor quality s les indicated significantly higher compressive stresses in the good quality versus poor quality coating. These results have revealed two extremes in the wear rates of these PCD coated carbides. It is suggested that the difference in diamond content between the two grades is not sufficient to account for the 3 orders-of-magnitude difference in the observed wear rates. However, the presence of intrusive veins of carbide material in the coatings, especially around the curved cutting tip, suggested that the macroscopic defects observed in the x-ray and SEM images were the major cause of the high wear rates in the poor quality s le.
Publisher: Elsevier BV
Date: 03-2018
Publisher: Trans Tech Publications, Ltd.
Date: 06-2010
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.654-656.1880
Abstract: Cold spray coatings are considered promising for surface protection of light metal substrates but the mechanisms of bonding and coating build-up are still poorly understood and are the subject of continuing debate. A variety of coating/substrate combinations have been characterised in detail using electron microscopy to examine the nature of the interparticle and particle/substrate interfaces. Through-thickness residual stress profiles obtained via neutron diffraction show that the internal stress varies significantly depending on the coating materials. The work will present a picture of the cold spray deposition process using different material ex les.
Publisher: Trans Tech Publications, Ltd.
Date: 02-2014
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.777.199
Abstract: Stress Corrosion Cracking (SCC) may be a serious problem in gas pipelines. This work studies the hardness and residual stress profiles in two nominally identical sections of adjacent pipe with similar environment and coating, one of which was affected by detectable SCC and the other that was not. The results show changes in texture, residual stress, plastic strain, and hardness at the pipe surface which may be responsible for the altered susceptibility to SCC.
Publisher: Elsevier BV
Date: 09-2015
Publisher: Royal Society of Chemistry (RSC)
Date: 2018
DOI: 10.1039/C8RA05906C
Abstract: Magnesium diboride (MgB 2 ) superconducting wires have demonstrated commercial potential to replace niobium–titanium (NbTi) in terms of comparable critical current density.
Publisher: Elsevier BV
Date: 2016
Publisher: Trans Tech Publications, Ltd.
Date: 05-2010
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.652.86
Abstract: Kowari is a neutron diffractometer at ANSTO’s research reactor OPAL. The instrument is dedicated to investigate residual strains and stresses in engineering s les or new materials. Besides its usage in engineering/strain-scanning it is more and more frequently being used for obtaining texture information related to materials science applications. In particular the possibility of using the gauge volume defining slit systems allows extracting local information from the diffraction peak, i.e. position, intensity, and width, without the need to cut the s le specimen. The instrument obtained its operating license in August 2008 to briefly describe the instruments parameters and capabilities, and give ex les of two typical applications since it went from commissioning into user mode.
Publisher: AIP Publishing
Date: 03-2019
DOI: 10.1063/1.5081909
Abstract: Energy-resolved neutron imaging experiments conducted on the Small Angle Neutron Scattering (SANS) instrument, Bilby, demonstrate how the capabilities of this instrument can be enhanced by a relatively simple addition of a compact neutron counting detector. Together with possible SANS s le surveying and location of the region of interest, this instrument is attractive for many imaging applications. In particular, the combination of the cold spectrum of the neutron beam and its pulsed nature enables unique non-destructive studies of the internal structure for s les that are opaque to other more traditional techniques. In addition to conventional white beam neutron radiography, we conducted energy-resolved imaging experiments capable of resolving features related to microstructure in crystalline materials with a spatial resolution down to ∼0.1 mm. The optimized settings for the beamline configuration were determined for the imaging modality, where the compromise between the beam intensity and the achievable spatial resolution is of key concern.
Publisher: Trans Tech Publications, Ltd.
Date: 02-2014
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.777.194
Abstract: Zirconium alloys are widely used in the nuclear industry because of their relative high strength, neutron transparency, resistance to high neutron-irradiation environment and corrosion resistance. One application for Zirconium alloy Zr-2.5Nb is the vacuum confinement vessel utilised in the cold neutron source of the OPAL research reactor at ANSTO. Having a total length of more the 3 meters, it is made of two sections joined using electron beam welding. The weld and the nearby regions are critical for the performance and integrity of the component and therefore understanding of the residual stresses development within the weld is important in connection to (i) evolution of fine dual phase α/b microstructure and crystallographic texture (ii) and stress-related radiation induced phenomena, such as grain growth, creep and sub-critical crack growth by delayed hydride cracking. The stresses were measured in and around an electron beam weld produced during the development of this component of the OPAL Cold Neutron Source. The effects of a large grain size in the weld were reduced by taking advantage of rotational symmetry and rotating the s le to increase the swept volume. Due to the heat-treatment after welding, the stresses were very low, less than 10% of the yield strength of the material, in both the hoop and axial directions. As a result of phase transformation effects during the welding process the final stresses are compressive in the weld, which reduces the likelihood of fracture or of hydride formation in this region. The highest stresses are in the parent material adjacent to the weld where the toughness is expected to be higher than in the weld material.
Publisher: Society of Economic Geologists
Date: 12-2021
DOI: 10.5382/ECONGEO.4885
Abstract: In many orogenic gold deposits, gold is located in quartz veins. Understanding vein development at the microstructural scale may therefore provide insights into processes influencing the distribution of gold, its morphology, and its relationship to faulting. We present evidence that deformation processes during aseismic periods produce characteristic quartz microstructures and crystallographic preferred orientations, which are observed across multiple deposits and orogenic events. Quartz veins comprise a matrix of coarse, subidiomorphic, and columnar grains overprinted by finer-grained quartz seams subparallel to the fault trace, which suggests an initial stage of cataclastic deformation. The fine-grained quartz domains are characterized by well-oriented quartz c-axis clusters and girdles oriented parallel to the maximum extension direction, which reveals that fluid-enhanced pressure solution occurred subsequent to grain refinement. Coarser anhedral gold is associated with primary quartz, whereas fine-grained, “dusty” gold trails are found within the fine-grained quartz seams, revealing a link between aseismic deformation and gold morphology. These distinct quartz and gold morphologies, observed at both micro- and macroscale, suggest that both seismic fault-valving and aseismic deformation processes are both important controls on gold distribution.
Publisher: Elsevier BV
Date: 11-2016
Publisher: Elsevier BV
Date: 2023
Publisher: Elsevier BV
Date: 12-2013
Publisher: Cambridge University Press (CUP)
Date: 27-12-2018
DOI: 10.1017/JOG.2018.100
Abstract: This contribution discusses results obtained from 3-D neutron diffraction and 2-D fabric analyser in situ deformation experiments on laboratory-prepared polycrystalline deuterated ice and ice containing a second phase. The two-phase s les used in the experiments are composed of an ice matrix with (1) air bubbles, (2) rigid, rhombohedral-shaped calcite and (3) rheologically soft, platy graphite. S les were tested at 10°C below the melting point of deuterated ice at ambient pressures, and two strain rates of 1 × 10 −5 s −1 (fast) and 2.5 × 10 −6 s −1 (medium). Nature and distribution of the second phase controlled the rheological behaviour of the ice by pinning grain boundary migration. Peak stresses increased with the presence of second-phase particles and during fast strain rate cycles. Ice-only s les exhibit well-developed crystallographic preferred orientations (CPOs) and dynamically recrystallized microstructures, typifying deformation via dislocation creep, where the CPO intensity is influenced in part by the strain rate. CPOs are accompanied by a concentration of [ c ]-axes in cones about the compression axis, coinciding with increasing activity of prismatic- a slip activity. Ice with second phases, deformed in a relatively slower strain rate regime, exhibit greater grain boundary migration and stronger CPO intensities than s les deformed at higher strain rates or strain rate cycles.
Publisher: Elsevier BV
Date: 08-2014
Publisher: Elsevier BV
Date: 12-2020
Publisher: Elsevier BV
Date: 05-2016
Publisher: Elsevier BV
Date: 2019
Publisher: Springer Science and Business Media LLC
Date: 20-05-2020
Publisher: American Physical Society (APS)
Date: 26-11-2019
Publisher: Elsevier BV
Date: 05-2012
Publisher: Informa UK Limited
Date: 23-10-2009
Publisher: Elsevier BV
Date: 03-2010
Publisher: Trans Tech Publications, Ltd.
Date: 11-2013
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.772.181
Abstract: In this work, autogenous laser welding was used to join thin plates of low carbon ferritic and austenitic stainless steel. Due to the differences in the thermo-physical properties of base metals, this kind of welds exhibit a complex microstructure, which frequently leads to an overall loss of joint quality. Four welded s les were prepared by using different sets of processing parameters, with the aim of minimizing the induced residual stress field. Microstructural characterization and residual strain scanning (by neutron diffraction) were used to assess the joints’ features.
Publisher: Springer Science and Business Media LLC
Date: 28-04-2020
Publisher: Elsevier BV
Date: 02-2011
Publisher: American Physical Society (APS)
Date: 03-10-2014
Publisher: Japan Welding Society
Date: 2017
Publisher: Trans Tech Publications, Ltd.
Date: 02-2014
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.777.243
Abstract: The unique and unusual state of matter represented by granular materials has historically made it very difficult to develop models of stress distributions and was previously not able to be explored experimentally in the required detail. This paper reports the application of the neutron diffraction strain scanning method, originally developed for residual stress measurements within engineering components, to the problem of the stress distribution in granular Fe under a consolidating pressure. Strains were measured in axial, radial, circumferential and an oblique direction using the neutron strain scanning diffractometer KOWARI at ANSTO (Sydney). The full stress tensor as a function of position was able to be extracted for both straight walled, converging and stepped dies.
Publisher: Trans Tech Publications, Ltd.
Date: 08-2002
Publisher: Springer Science and Business Media LLC
Date: 26-08-2021
Publisher: SAGE Publications
Date: 22-08-2011
Abstract: When neutron diffraction is used to measure residual stresses, estimates of the unstressed lattice spacing ( d 0 ) are often required. These are generally measured on a s le that is considered representative of the component. In the case of welded s les, the possibility of variation in weld shape between the d 0 s le and the area where stresses are determined must be taken into account. To assess this, d 0 values are measured on an area considered representative of the s le, and then are re-measured on a s le cut from the actual strain measurement plane. The residual stresses are re-calculated with these new d 0 values and the results compared to those based on the initial d 0 measurement. Methods of estimating these errors are discussed. The errors in residual stress that arise from the spatial variation of d 0 values are greater than the commonly reported peak fitting errors. These errors can be estimated and should be included in the reported residual stress measurements. Cutting a d 0 s le from the measurement plane makes this a destructive technique.
Publisher: MDPI AG
Date: 11-08-2022
DOI: 10.3390/MA15165537
Abstract: Cermet coatings deposited using high-velocity oxy-fuel (HVOF) are widely used due to their excellent wear and corrosion resistance. The new agglomeration–rapid sintering method is an excellent candidate for the preparation of WC–Co–Cr feedstock powders. In this study, four different WC–10Co–4Cr feedstock powders containing WC particles of different sizes were prepared by the new agglomeration–rapid sintering method and deposited on steel substrates using the HVOF technique. The microstructures and mechanical properties of the coatings were investigated using scanning electron microscopy, X-ray diffraction, nanoindentation, and Vickers indentation. The through-thickness residual stress profiles of the coatings and substrate materials were determined using neutron diffraction. We found that the microstructures and mechanical properties of the coatings were strongly dependent on the WC particle size. Decarburization and anisotropic mechanical behaviors were exhibited in the coatings, especially in the nanostructured coating. The coatings containing nano- and medium-sized WC particles were dense and uniform, with a high Young’s modulus and hardness and the highest fracture toughness among the four coatings. As the WC particle size increased, the compressive stress in the coating increased considerably. Knowledge of these relationships enables the optimization of feedstock powder design to achieve superior mechanical performance of coatings in the future.
Publisher: Society of Exploration Geophysicists
Date: 27-08-2018
Publisher: Elsevier BV
Date: 04-2022
Publisher: Elsevier BV
Date: 08-2003
Publisher: Springer Science and Business Media LLC
Date: 20-11-2020
Publisher: Elsevier BV
Date: 11-2006
Publisher: Springer Science and Business Media LLC
Date: 26-04-2013
Publisher: Elsevier BV
Date: 02-2019
Publisher: Elsevier BV
Date: 08-2019
Publisher: Trans Tech Publications, Ltd.
Date: 09-2013
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.768-769.741
Abstract: Insulated rail joints (IRJs) are an integral part of the rail track signaling system and pose significant maintenance and replacement costs due to their low and fluctuating service lives. Failure occurs mainly in rail head region, bolt- holes of fishplates and web-holes of the rails. Propagation of cracks is influenced by the evolution of internal residual stresses in rails during rail manufacturing (hot-rolling, roller-straightening, and head-hardening process), and during service, particularly in heavy rail haul freight systems where loads are high. In this investigation, rail head accumulated residual stresses were analysed using neutron diffraction at the Australian Nuclear Science and Technology Organisation (ANSTO). Two ex-service two head-hardened rail joints damaged under different loading were examined and results were compared with those obtained from an unused rail joint reference s le in order to differentiate the stresses developed during rail manufacturing and stresses accumulated during rail service. Neutron diffraction analyses were carried out on the s les in longitudinal, transverse and vertical directions, and on 5mm thick sliceed s les cut by Electric Discharge Machining (EDM). For the rail joints from the service line, irrespective of loading conditions and in-service times, results revealed similar depth profiles of stress distribution. Evolution of residual stress fields in rails due to service was also accompanied by evidence of larger material flow based on reflected light and scanning electron microscopy studies. Stress evolution in the vicinity of rail ends was characterised by a compressive layer, approximately 5 mm deep, and a tension zone located approximately 5- 15mm below the surfaces. A significant variation of d0 with depth near the top surface was detected and was attributed to decarburization in the top layer induced by cold work. Stress distributions observed in longitudinal slices of the two different deformed rail s les were found to be similar. For the undeformed rail, the stress distributions obtained could be attributed to variations associated with thermo-mechanical history of the rail.
Publisher: Elsevier BV
Date: 06-2022
Publisher: Trans Tech Publications, Ltd.
Date: 03-2008
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.571-572.315
Abstract: Thermal and cold spraying encompasses a great variety of techniques for deposition of fully or partially molten or cold particles of material to produce coatings with a specific microstructure and properties for the purpose of surface enhancement. Among the many factors influencing sprayed coating integrity, residual stress is very important since it will be the driving force for possible crack propagation and consequent coating failure. The very complex physical processes occurring during coating deposition make first principles treatment difficult. A number of empirical models have been proposed to predict and describe quantitatively the stress distribution in the coating/substrate system. However, there are a limited number of experimental measurements on through-thickness stress distribution and for only a few materials and few spraying techniques, to validate any model and to define its area of applicability. Several metal and ceramic coatings produced by different spraying techniques were measured by means of neutron diffraction. Through-thickness stress profiles were obtained and treated in the frame of the empirical progressive coating deposition model. The comparison between experimental and simulated results is discussed.
Publisher: Trans Tech Publications, Ltd.
Date: 2010
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.638-642.2823
Abstract: In response to the development of new materials and the application of materials and components in new technologies the direct measurement, calculation and evaluation of textures and residual stresses has gained worldwide significance in recent years. Non-destructive analysis for phase specific residual stresses and textures is only possible by means of diffraction methods. The determination of global texture and the local variation of texture for ex le by inhomogeneous deformation are very important due to the coherence between the texture and the physical and mechanical properties of materials.
Publisher: Springer Science and Business Media LLC
Date: 07-05-2020
Publisher: Springer Science and Business Media LLC
Date: 29-07-2020
Publisher: Springer Science and Business Media LLC
Date: 08-07-2020
Publisher: International Union of Crystallography (IUCr)
Date: 25-03-2022
DOI: 10.1107/S1600576722002308
Abstract: HRTex is a new texture data processing tool for two-dimensional position-sensitive area detectors on monochromatic neutron diffractometers. With the aim of improving the resolution and accuracy of pole figure calculations, HRTex treats the raw data of the area detector for each pixel and projects the intensity of each pixel directly onto a high-resolution pole figure. With the resultant refinement of the resolution, HRTex can distinguish close texture peaks with a flexible resolution setting and reduced information loss. Test results of HRTex on the data sets of two s les measured by two different neutron facilities are analysed, and the improvements in accuracy, resolution and efficiency of the pole figure calculation are discussed.
Publisher: Trans Tech Publications Ltd.
Date: 15-09-2005
Publisher: Trans Tech Publications, Ltd.
Date: 02-2014
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.777.213
Abstract: Insulated rail joints (IRJs) are a primary component of the rail track safety and signalling systems. Rails are supported by two fishplates which are fastened by bolts and nuts and, with the support of sleepers and track ballast, form an integrated assembly. IRJ failure can result from progressive defects, the propagation of which is influenced by residual stresses in the rail. Residual stresses change significantly during service due to the complex deformation and damage effects associated with wheel rolling, sliding and impact. IRJ failures can occur when metal flows over the insulated rail gap (typically 6-8 mm width), breaks the electrically isolated section of track and results in malfunction of the track signalling system. In this investigation, residual stress measurements were obtained from rail-ends which had undergone controlled amounts of surface plastic deformation using a full scale wheel-on-track simulation test rig. Results were compared with those obtained from similar investigations performed on rail ends associated with ex-service IRJs. Residual stresses were measured by neutron diffraction at the Australian Nuclear Science and Technology Organisation (ANSTO). Measurements with constant gauge volume 3x3x3 mm 3 were carried in the central vertical plane on 5mm thick sliced rail s les cut by an electric discharge machine (EDM). Stress evolution at the rail ends was found to exhibit characteristics similar to those of the ex-service rails, with a compressive zone of 5mm deep that is counterbalanced by a tension zone beneath, extending to a depth of around 15mm. However, in contrast to the ex-service rails, the type of stress distribution in the test-rig deformed s les was apparently different due to the localization of load under the particular test conditions. In the latter, in contrast with clear stress evolution, there was no obvious evolution of d 0 . Since d 0 reflects rather long-term accumulation of crystal lattice damage and microstructural changes due to service load, the loading history of the test rig s les has not reached the same level as the ex-service rails. It is concluded that the wheel-on-rail simulation rig provides the potential capability for testing the wheel-rail rolling contact conditions in rails, rail ends and insulated rail joints.
Publisher: MDPI AG
Date: 09-08-2017
DOI: 10.3390/MET7080306
Publisher: Elsevier BV
Date: 09-2021
Publisher: Elsevier BV
Date: 09-2015
Publisher: Elsevier BV
Date: 05-2021
Publisher: Trans Tech Publications, Ltd.
Date: 03-2008
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.571-572.51
Abstract: Cold-drawing is employed to fabricate wires and rods, which are mainly used as structural reinforcements in construction as well as in the tyre industry. As a consequence of processing, a residual stress profile is developed. In this paper, residual stress profiles are measured by neutron diffraction in cold-drawn pearlitic steel rods subjected to different deformations (true strain from 0.3 to 1.7). The results show that the residual stress profile produced by cold-drawing is similar in all the s les, irrespective of the degree of deformation.
Publisher: Elsevier BV
Date: 09-2016
Publisher: AIP Publishing
Date: 2020
DOI: 10.1063/1.5120422
Abstract: Recently, a number of reconstruction algorithms have been presented for residual strain tomography from Bragg-edge neutron transmission measurements. In this paper, we examine whether strain tomography can also be achieved using diffraction instruments. We outline the proposed method and develop a suitable reconstruction algorithm. This technique is demonstrated in simulation, and a proof-of-concept experiment is carried out, where the strain field in an axisymmetric s le is reconstructed and validated using conventional diffraction strain scans.
Publisher: IOP Publishing
Date: 11-2010
Publisher: Elsevier BV
Date: 08-2017
Publisher: IOP Publishing
Date: 11-2010
Publisher: Springer Science and Business Media LLC
Date: 02-05-2019
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 04-2018
Publisher: Springer Science and Business Media LLC
Date: 2004
Publisher: Elsevier BV
Date: 12-2017
Publisher: Elsevier BV
Date: 2018
Publisher: American Geophysical Union (AGU)
Date: 10-2013
DOI: 10.1002/GGGE.20246
Publisher: Trans Tech Publications, Ltd.
Date: 06-2010
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.654-656.2527
Abstract: Diamond composite materials are classified as superhard and exhibit exceptional abrasive resistance. Cemented tungsten carbide tools with a thick coating of diamond composite material (PCD) are finding increased usage in materials cutting operations in manufacturing, mining, minerals, gas and petroleum exploration and civil construction industries. Two major advantages derived from these coated tools are: (a) increased wear resistance and hence increased life-span of these tools and (b) their proven ability to handle “difficult-to-machine” materials as well as high-strength, extremely abrasive materials such as quartz-rich rocks, granites and basalts. In this research, the variability of the wear resistance of PCD coated tungsten carbide is correlated with microstructural variations. A detailed study of the microstructure and distribution of phases was performed using SEM, cathodoluminescence (CL) imaging, direct x-ray imaging, Raman spectroscopy as well as residual stress measurements using neutron diffraction.
Publisher: Elsevier BV
Date: 08-2018
Publisher: Trans Tech Publications, Ltd.
Date: 08-2002
Publisher: Springer Science and Business Media LLC
Date: 14-08-2020
Publisher: Springer International Publishing
Date: 09-11-2017
Publisher: Springer Science and Business Media LLC
Date: 18-12-2019
Publisher: Elsevier BV
Date: 06-2014
Publisher: AIP Publishing
Date: 15-04-2012
DOI: 10.1063/1.4706563
Abstract: In this paper, we report the phase transition behavior of ternary relaxor ferroelectric single crystals of 0.25Pb(In1/2Nb1/2)O3-0.44Pb(Mg1/3Nb2/3)O3-0.31PbTiO3 subject to a uniaxial mechanical stress up to 400 MPa. The resultant in situ neutron diffraction data are interpreted in terms of the polarization rotation theory and provide direct structural evidence for the stress-induced polarization rotation pathway deduced from studies of macroscopic physical properties under stress. It is suggested that an intermediate, metastable orthorhombic phase is induced above a critical pressure of ∼75 MPa. This critical stress level appears to be unaffected by s le poling although the ground states (at zero stress) for the poled and unpoled crystals are different. The critical stress level, however, does decrease with increasing temperature. The elastic behavior of the intermediate phases is also studied based on a calculation of the associated lattice strains.
Publisher: Elsevier BV
Date: 03-2017
Publisher: Elsevier BV
Date: 09-2019
Publisher: Springer Science and Business Media LLC
Date: 08-11-2016
DOI: 10.1038/SREP36660
Abstract: Superconducting wires are widely used in fabricating magnetic coils in fusion reactors. In consideration of the stability of 11 B against neutron irradiation and lower induced radio-activation properties, MgB 2 superconductor with 11 B serving as boron source is an alternative candidate to be used in fusion reactor with severe irradiation environment. In present work, a batch of monofilament isotopic Mg 11 B 2 wires with amorphous 11 B powder as precursor were fabricated using powder-in-tube (PIT) process at different sintering temperature, and the evolution of their microstructure and corresponding superconducting properties was systemically investigated. Accordingly, the best transport critical current density ( J c ) = 2 × 10 4 A/cm 2 was obtained at 4.2 K and 5 T, which is even comparable to multi-filament Mg 11 B 2 isotope wires reported in other work. Surprisingly, transport J c vanished in our wire which was heat-treated at excessively high temperature (800 °C). Combined with microstructure observation, it was found that lots of big interconnected microcracks and voids that can isolate the MgB 2 grains formed in this whole s le, resulting in significant deterioration in inter-grain connectivity. The results can be a constructive guide in fabricating Mg 11 B 2 wires to be used as magnet coils in fusion reactor systems such as ITER-type tokamak magnet.
Publisher: Elsevier BV
Date: 2022
Publisher: Informa UK Limited
Date: 11-2012
Publisher: Geological Society of America
Date: 27-05-2022
DOI: 10.1130/G50217.1
Abstract: Stress on seismogenic faults provides critical information about how much elastic energy is stored in the crust and released by earthquakes, which is crucial in understanding earthquake energetics and recurrence. However, determining post-earthquake stress states on faults remains challenging because current borehole methods are rarely applicable to damaged fault zone rocks. We applied neutron texture analysis to gouge s les of the 1999 Chi-Chi earthquake in Taiwan to infer the stress state after the earthquake. Results indicate that the clay fabric within the principal slip zone is orthogonal to the fault plane, whereas outside the principal slip zone the fabric is predominantly parallel to the bedding-parallel fault plane. We suggest that the clay fabric in the slip zone was first neutralized by the coseismic fluidization caused by thermal pressurization and later re-oriented to the new direction of post-earthquake principal stress. Such stress orientation is consistent with the orientations inferred from core-scale fault slip data and dislocation models constrained from global navigation satellite system displacements. If thermal pressurization is a ubiquitous process during earthquakes, gouge fabrics can be used to help probe the post-earthquake stress state of faults.
Publisher: Elsevier BV
Date: 05-2020
Publisher: American Association of Petroleum Geologists
Date: 2017
Publisher: Informa UK Limited
Date: 03-2010
Publisher: CSIRO Publishing
Date: 2015
DOI: 10.1071/RS15011
Abstract: Major polar ice sheets and ice caps experience cycles of variable flow during different glacial periods and as a response to past warming. The rate and localisation of deformation inside an ice body controls the evolution of ice microstructure and crystallographic fabric. This is critical for interpreting proxy signals for climate change, with deformation overprinting and disrupting stratigraphy deep under ice caps due to the nature of the flow. The final crystallographic fabric in polar ice sheets provides a record of deformation history, which in turn controls the flow properties of ice during further deformation and affects geophysical sensing of ice sheets. For ex le, identification of layering in ice sheets, using seismic or ice radar techniques, is attributed to grain size changes and fabric variations. Such information has been used to provide information on climate state and its changes over time, and as the Fourth Intergovernmental Panel on Climate Change (IPCC) Report (Solomon et al. 2007) points out there is currently still a lack of understanding of internal ice-sheet dynamics. To answer this we have recently conducted experiments at the Australian Nuclear Science and Technology Organisation (ANSTO) to collect fully quantitative microstructural data from polycrystalline heavy water (D2O) ice deformed in a dynamic regime. The ice and temperature (–7°C) chosen for this study is used as a direct analogue for deforming natural-water ice as it offers a unique opportunity to link grain size and texture evolution in natural ice at –10°C. Results show a dynamic system where steady-state rheology is not necessarily coupled to microstructural and crystallographic fabric stability. This link needs to be taken into account to improve ice-mass-deformation modelling critical for climate change predictions.
Publisher: Informa UK Limited
Date: 29-01-2016
Publisher: Elsevier BV
Date: 07-2022
Publisher: Springer Science and Business Media LLC
Date: 22-07-2021
Publisher: Springer Science and Business Media LLC
Date: 08-2020
Publisher: Trans Tech Publications, Ltd.
Date: 02-2014
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.777.78
Abstract: Cold coiling of high tensile steel rod into helical coil springs for the automotive industry is a new technique being implemented amongst spring manufacturers worldwide. To characterise this coil production process, the neutron strain scanning technique has been employed to non-destructively elucidate the influence production stages have on the tri-axial residual stress state. S les investigated represented key production steps in the cold-coil forming process: Cold coiling Tempering Hot setting Hot peening Shot peening. Investigations revealed that the stress field was axi-symmetrical, that the dominant variation in all s les occurred along the hoop direction (helical circumference), whilst the radial and axial stresses are substantially lower. Accurate two-dimensional stress maps of the rod cross section have been compiled revealing key features associated with the cold coiling step. Comparison of the stress fields after each production step revealed altered stress values. The final shot peening process stage not only reduced stress concentrations at the internal bore, but contributed to the establishment of favourable surface residual stress conditions that enhance the fatigue life of the final product.
Publisher: Informa UK Limited
Date: 07-2013
Publisher: Elsevier BV
Date: 04-2019
Publisher: Elsevier BV
Date: 11-2014
Publisher: Wiley
Date: 25-04-2020
DOI: 10.1111/JACE.17156
Publisher: Materials Research Forum LLC
Date: 05-01-2020
Publisher: Trans Tech Publications, Ltd.
Date: 08-2017
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.905.165
Abstract: A great variety of techniques are nowadays used to spray coatings with different functionality and properties for the purpose of surface enhancement. Depending on application and design, these can be thermal (plasma or high-velocity oxy-fuel are the most widely used) and warm or cold spraying, which are known to generate considerable residual stresses. This stress is a function of the spaying process as well as the material and thickness of the coating-substrate system. The mechanical integrity of coatings is critical for certain applications, e.g. wear resistant and thermal-barrier coatings, hence residual stress control and mitigation are essential in preventing the coating’s mechanical failure, improving the coating’s performance and the its operational lifetime. Although hole drilling technique or x-ray diffraction combined with layer removal method can be applicable for stress measurements in coatings, the neutron diffraction stress analysis also provides an effective and efficient tool for non-destructive through-thickness stress measurements with a commensurately high resolution, down to 0.1-0.2 mm. The most recent results of neutron diffraction stress measurements in coating systems are presented herein.
Publisher: Elsevier BV
Date: 03-2015
Publisher: Elsevier BV
Date: 02-2007
Publisher: American Physical Society (APS)
Date: 13-12-2018
Publisher: Elsevier BV
Date: 11-2006
Publisher: Elsevier BV
Date: 04-2020
Publisher: Wiley
Date: 22-09-2017
DOI: 10.1111/JMI.12472
Abstract: Three techniques are used to measure crystallographic preferred orientations (CPO) in a naturally deformed quartz mylonite: transmitted light cross-polarized microscopy using an automated fabric analyser, electron backscatter diffraction (EBSD) and neutron diffraction. Pole figure densities attributable to crystal-plastic deformation are variably recognizable across the techniques, particularly between fabric analyser and diffraction instruments. Although fabric analyser techniques offer rapid acquisition with minimal s le preparation, difficulties may exist when gathering orientation data parallel with the incident beam. Overall, we have found that EBSD and fabric analyser techniques are best suited for studying CPO distributions at the grain scale, where in idual orientations can be linked to their source grain or nearest neighbours. Neutron diffraction serves as the best qualitative and quantitative means of estimating the bulk CPO, due to its three-dimensional data acquisition, greater s le area coverage, and larger s le size. However, a number of s ling methods can be applied to FA and EBSD data to make similar approximations.
Publisher: Trans Tech Publications, Ltd.
Date: 02-2014
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.777.165
Abstract: Diamond composite materials are being used increasingly in cutting tools for both the mining and manufacturing industries. Except for the low pressure CVD and SPS methods, most SiC based diamond composites are produced under high pressure and high temperature (HPHT). The dominant binder phase is SiC and these composites are classed as thermally stable and are referred to as TSDC (thermally stable diamond composite). TSDC composites are produced by reactive sintering either within the diamond stability field, ~1500°C and ~5.5 GPa, or in the graphite phase field at ~1550°C and ~2 - 3.5 GPa as originally patented by Ringwood. Unlike the traditional polycrystalline diamond composite (PCD) that use Co as the binder phase and operate under restricted temperature conditions, usually less the 800°C, TSDC is Co-free allowing the operational temperature range for TSDC to be extended substantially. Extensive experimental research has been conducted at the CSIRO (Commonwealth Scientific & Industrial Research Organization) Rock Cutting Laboratory to assess the quality of TSDC products through a series of in-house tests that have been developed (abrasive wear test, compressive and shear testing) to facilitate their use in the mining industry. The focus is to prevent TSDC from premature failures in drilling and cutting operations. Since the wear resistance and performance in general, of TSDC cutting elements are strongly dependent on the phase composition, phase distribution (microstructures) and phase interaction (microstresses), detailed studies of TSDC have been undertaken using optical, SEM (with EDS and CL), Raman microscopy and radiographic imaging of macro defects as well as x-ray and neutron diffraction. Residual stress measurements were made using the neutron diffractometer Kowari at OPAL research reactor in the diamond and SiC phases in two TSDC s les. The microstresses that developed in these phases as a result of quenching from high sintering pressure and temperature and the mismatch of the thermo-mechanical properties of SiC matrix and diamond inclusions were evaluated. The matrix-inclusion concept has also been used to calculate stress partition in the phases of the TSDC products that can be directly comparable with the experimental data and give clearer interpretation of the experimental results.
Publisher: Elsevier BV
Date: 03-2022
Publisher: Elsevier BV
Date: 10-2014
Publisher: ASMEDC
Date: 2011
Abstract: The numerical application of solid-state phase transformation kinetics relating to conventional welding of ferritic steels is presented. The inclusion of such kinetics in weld models is shown to be necessary for capturing the post-weld residual stress field. To this end, a comparison of two approaches is outlined: a semi-empirical approach that uses thermodynamic transformation kinetics to predict phase morphology and a fully empirical approach that directly links local material temperature to the present constituent phase(s). The semi-empirical analysis begins with prediction of TTT diagrams using thermodynamic principles for ferritic steels. The data is then converted to CCT diagrams using the Scheil-Avrami additive rule, including austenite grain growth kinetics. This information is used to predict the phases present under varying peak temperatures and cooling rates. In the fully empirical approach, dilatometric experiments of steel s les are performed during heating to simulate expected welding conditions. The constitutive response of the s le is then used as input for the subsequent numerical weld analyses. Input derived from each technique is transferred into weld models developed using the Abaqus finite element package. Model validation is carried out by direct comparison with neutron diffraction residual stress measurements on two beams of SA508 Gr.3 Cl.1 steel subjected to autogenous beam TIG welds under varying torch speeds, heat input and preheat conditions.
Publisher: MDPI AG
Date: 21-03-2017
DOI: 10.3390/EN10030409
Publisher: Elsevier BV
Date: 02-2020
Publisher: Trans Tech Publications, Ltd.
Date: 02-2014
DOI: 10.4028/WWW.SCIENTIFIC.NET/MSF.777.205
Abstract: Cold spray is a material deposition technique in which powdered metals are deposited onto metallic and glass substrates as a means of improving functionality, repair or protection of the underlying substrate. The residual stress that builds up in the material during spraying is closely linked to the coating’s integrity and the bonding mechanism. Neutron diffraction residual stresses measurements were carried out at the OPAL research reactor, ANSTO, using the KOWARI strain scanner to investigate an Al-6061 s le with a fine through-thickness resolution of 0.5 mm. The experimentally determined through thickness stress profiles of the macroscopically thick coatings were used to validate FE calculations made for 100 μm thick coatings using the Smooth Particle Hydrodynamics, SPH, techniques. A pronounced plastic strain gradient was apparent in the tested and modelled s les indicative of the significant residual macro-stresses which develop in the cladding/substrate during the deposition. Around the deposited particle’s periphery (in the jetting region) the temperatures are significant, this lends itself to the presence of grain refinement at the periphery of sprayed particles and the propagation of dynamic recrystallization which is closely coupled with the thermal softening of the particle.
Publisher: American Physical Society (APS)
Date: 03-05-2018
Publisher: American Physical Society (APS)
Date: 09-10-2017
Publisher: Elsevier BV
Date: 11-2018
Publisher: Elsevier BV
Date: 12-2022
Publisher: Elsevier BV
Date: 2017
Publisher: Trans Tech Publications Ltd.
Date: 15-07-2005
Publisher: Elsevier BV
Date: 2019
Publisher: Elsevier BV
Date: 12-2020
Publisher: Elsevier BV
Date: 08-2016
Publisher: Elsevier BV
Date: 03-2021
Location: Australia
Start Date: 2017
End Date: 12-2023
Amount: $381,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 12-2018
End Date: 12-2022
Amount: $320,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 03-2019
End Date: 03-2025
Amount: $4,889,410.00
Funder: Australian Research Council
View Funded Activity