In Situ Diffraction Study of the High‐Temperature Decomposition of t′‐Zirconia

• DOI: 10.1111/jace.13249
• Publication Date: 2014-09-26T10:41:26Z
• Authors: Jessica A. Krogstad; Yan Gao; Jianming Bai; Jun Wang; Don M. Lipkin; Carlos G. Levi
• Keywords: Tetragonal crystal system; Metastability

The mechanisms of phase destabilization upon aging the metastable t′ yttria‐stabilized zirconia ( YSZ ) are poorly understood, despite its broad application in thermal barrier coatings. To provide insight, synchrotron X‐ray diffraction XRD with a quadrupole lamp furnace is used to examine temperature response, including expansion and evolution, 9 mol% (8 wt%) YO 1.5 t′‐ 8 . equilibrated powders ranging from 0 18.4 also investigated better understand effect composition on anisotropy. T c/t for estimated be 1640°C. Full decomposition into coherent mixture Y‐lean tetragonal t Y‐rich cubic c that coarsen over time observed at elevated temperatures; however, quenching, reappears profile. This supports our evolving understanding by aged samples microstructural artifact due coherency strain between phases.