Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7898455 | Journal of the European Ceramic Society | 2018 | 4 Pages |
Abstract
A novel fine-grained orthorhombic ZrO2 ceramic stabilized with 12â¯mol% Ta doping was fabricated by spark-plasma sintering from home-made powders, and its high-temperature mechanical properties evaluated for the first time by compressive creep tests in both Ar and air. It was found that the high-temperature plasticity of the ceramic deformed in Ar, under which the Ta-doped orthorhombic ZrO2 is a black suboxide with abundant oxygen vacancies in its crystal structure, is controlled by grain boundary sliding (stress exponent â¼2, and activation energy â¼780-800â¯kJ/mol). However, the high-temperature plasticity of the ceramic deformed in air, under which the Ta-doped orthorhombic ZrO2 is a white oxide due to the elimination in situ of oxygen vacancies, is controlled by recovery creep (stress exponent â¼3, and activation energy â¼750â¯kJ/mol). It was also observed that black Ta-doped orthorhombic ZrO2 is more creep resistant than its white counterpart with the same grain size, and that the former deforms as the more conventional Y2O3-stabilized ZrO2 does.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Gabriele Sponchia, Bibi Malmal Moshtaghioun, Pietro Riello, Alvise Benedetti, Diego Gómez-GarcÃa, Arturo DomÃnguez-RodrÃguez, Angel L. Ortiz,