Abstract
The present work was carried out in order to clarify the heterogeneities in the structure of a commercial PSZ containing 2.5 mol% Y2O3 and to observe the microstructural changes with post annealing.
Besides existence of coagulated Al2O3 inclusions, it was found that Y2O3 concentration in the compact fluctuated in the range from 2 to 3 mol% (the period of the segregated zone was about 5–10 μm). When the compact was annealed at 1673 K, grains in the Y2O3 enriched zone (cubic ZrO2) grew preferentially.
The difference in Y2O3 concentration between cubic and tetragonal grains decreased with rising annealing temperature, and they became almost equal in the concentration at 2243 K, eventually. The observation of these annealed structures was carried out by means of SEM and TEM.
