Abstract
The stress-strain state of ZrB2-SiC ultra-high-temperature ceramics, produced using commercial powders with different impurity levels, was investigated by X-ray diffraction. Upon analysis of ZrB2 and SiC diffraction lines shift, the level of thermal stresses (strains) of the different phases was determined. An increase of internal stresses in ceramics with rising viscous-brittle transition temperatures, Tve, was attributed to increased grain boundary strength. Ceramics, for which high Tve and high level of internal stresses were estimated, exhibited high strength, up to 700 MPa at 1400 °C. A field of compressive thermal stresses in the matrix phase resulted to be necessary for achieving high strength at low-temperatures. On the contrary, the presence of low-melting impurities at the grain boundaries negatively impacted on the stress level in ZrB2 boundaries in the high temperature regime.
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.