An investigation of the zirconia-gadolinia system

Abstract The effects of adding up to 50 mole % of gadolinia on the transformation of zirconia have been investigated by differential thermal analysis and X-ray diffraction. Zirconia and gadolinia ceramic grade powders, suitably homogenized, have been submitted to a solution heat treatment at 1450 °C for 10 h in air. The results indicate that the solution of a small amount of gadolinia in zirconia increases the thermal hysteresis of the zirconia tetragonal-monoclinic transformation, that the presence of 30 mole % or more of gadolinia stabilizes the zirconia in the cubic form, and that the presence of zirconia hinders the cubic-monoclinic transformation of residual gadolinia. The properties of powders obtained after solution treatment should enable them to be sinterable to dense bodies.