Phase change and mechanical properties of ZrO2-Y2O3 solid electrolyte after ageing

For the system ZrO2Y2O3 containing from 4.5 to 8.0 mole% Y2O3, the crystal structure, mechanical properties, electrical conductivity, and performance as solid electrolyte were investigated before and after ageing at low temperature. For the partially stabilized Y2O3ZrO2 alloys (Y-PSZ) containing from 4.5 to 6.0 mole% Y2O3, the amount of monoclinic ZrO2 increases slightly while the electrical conductivity decreases slightly. The bending strength and thermal shock resistance, however, retain their high value (a factor of two or three higher than that of a fully stabilized Y2O3ZrO2 (Y-FSZ) of 8 mole% Y2O3) without change after ageing.