PARAMAGNETIC-DEFECT KINETICS IN YTTRIA-STABILIZED ZIRCONIA

The concentration and the thermal stability of paramagnetic defects induced by different treatments in ZrO2-12%Y2O3 and ZrO2-24%Y2O3 are analyzed by studying their EPR signals. The spectroscopic features of the EPR spectra show that the same types of centers are created in X-ray or UV-light irradiated samples and in samples treated in reducing atmosphere at high temperature. The center density depends, in X-ray and UV-light irradiated samples, only on the irradation dose, and the defect stability is the same in all crystals, independently on the Y2O3 concentration. After reduction of the same samples, the center stability is higher and the center density is different in crystals with different Y2O3 content.