Grain-boundary sliding in high-temperature ceramics: mechanical spectroscopy of high-purity magnesium oxide. The demise of elastic behaviour in materials stressed at sufficiently high temperature limits the usefulness of ceramics for structural applications, and is also responsible for reduced wave speeds and associated attenuation of seismic waves in the Earth's interior. Yet the nature of the transition in fine-grained materials tested at high temperature from elastic through anelastic to vis ....Grain-boundary sliding in high-temperature ceramics: mechanical spectroscopy of high-purity magnesium oxide. The demise of elastic behaviour in materials stressed at sufficiently high temperature limits the usefulness of ceramics for structural applications, and is also responsible for reduced wave speeds and associated attenuation of seismic waves in the Earth's interior. Yet the nature of the transition in fine-grained materials tested at high temperature from elastic through anelastic to viscous rheology remains poorly understood. Through a combination of mechanical testing by torsional forced oscillation/ microcreep methods of carefully fabricated and characterised specimens of polycrystalline MgO and associated micro-mechanical modelling we seek to clarify this fundamental and general aspect of high-temperature mechanical behaviour.Read moreRead less
An experimental study of trace element equilibria during metamorphism. The analytical methods and experimental data to be developed will enable an Australian team to become world leaders in determining pressures and temperatures of mineral growth that correspond to a range of depths and temperature gradients in the Earth tha t is wider than accessible previously. Obtaining this information from small zones within single grains will allow determination of rates of change, and give us a detailed p ....An experimental study of trace element equilibria during metamorphism. The analytical methods and experimental data to be developed will enable an Australian team to become world leaders in determining pressures and temperatures of mineral growth that correspond to a range of depths and temperature gradients in the Earth tha t is wider than accessible previously. Obtaining this information from small zones within single grains will allow determination of rates of change, and give us a detailed picture of how the host rock has evolved, even from very small samples. One application would be checking the origin of relatively common minerals for whether they could be associated with diamonds.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE100100236
Funder
Australian Research Council
Funding Amount
$180,000.00
Summary
Facilities for spectroscopy and diffraction at high pressures. The provision of infrastructure for the study of novel materials under high pressures will enhance Australia's capability in creating new materials and in creating new devices that meet needs in communication, environment and medicine applications. The new facility will enable researchers to understand the response of structures to extreme pressures and will exploit the unique capabilities of the synchrotron light.