On the Stability of Tetragonal Precipitates in Y2O3-Partially Stabilized ZrO2 Single Crystals

The stability of the tetragonal precipitates against the tetragonal-to-monoclinic transformation in Y₂O₃-partially-stabilized ZrO₂ (Y-PSZ) single crystals with two different Y₂O₃ compositions (3.4 and 4.7 https://www.w3.org/1998/Math/MathML"> m o https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003421290/07e4de97-c68f-4ca1-95b4-28d8b410031d/content/eq110.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> ) has been investigated using Raman spectroscopy and transmission electron microscopy. Aging at 1600°C causes precipitation and coarsening of tetragonal particles in the cubic matrix and a concomitant decrease in their stability. The particle stability appears to be unrelated to their size and shape; rather, particle-particle interactions seem to be important in determining the M_S temperature. The internal microstructure of the tetragonal and monoclinic phases are discussed.