Abstract
The phase relations and equation of state of ZrO2were investigated up to 100 GPa by means ofin situobservation using laser heating in a diamond anvil cell and synchrotron radiation. A cotunnite (PbCl2)-type phase, which appears above 12.5 GPa, is stable to a pressure of 100 GPa and a temperature of 2500 K. No post-cotunnite phase was observed under the present experimental conditions. The unit-cell parameters and the volumes of the cotunnite-type ZrO2were determined as a function of pressure at room temperature using a laser-annealing technique. The cotunnite-type ZrO2shows rather isotropic compression. The bulk modulus calculated using the Birch–Murnaghan equations of state is 278 GPa, which suggests that high-density ZrO2is a candidate for potentially very hard materials.In situhigh-temperature experiments performed below 12.5 GPa revealed that a tetragonal fluorite (CaF2)-type phase is stable up to 3000 K, although a cubic fluorite-type phase has been assumed to exist in this high-temperature regime. The result suggests the possibility that stoichiometric ZrO2does not show the cubic structure up to the melting temperature.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.