Improved stress measurement of YSZ by Raman spectroscopy: Effect of yttrium segregation‐dependent tetragonality
Huangyue Cai, Xing Zhang, Li Hu, Fangwei Guo, Xin Wang, Xiaofeng Zhao, Na Ni, Ping Xiao
Abstract
Abstract The Raman peaks of metastable yttria‐stabilized zirconia changed with annealing at high temperatures even before the onset of transformation to any monoclinic phase, leading to ambiguous determination of stress‐free references. In this work, the evolution of the Raman bands of metastable YSZ with annealing for different times at different high temperatures were analyzed using the tetragonality variation, which was consequent on the cation redistribution activated by thermal diffusion. The Raman bands linearly varied with the volume weighted tetragonality over the range studied (1.009‐1.015). The cation diffusion changed the bonds length and the associated Raman modes frequencies. A semiempirical equation was established to amend the available calculation for residual stresses by Raman spectroscopy, based on the variation coefficients ratio of two E g Raman modes (465 cm −1 and 640 cm −1 ).