Effects of gallia additions on sintering behavior of Ce0.8Gd0.2O1.9 ceramics prepared by commercial powders

The densification behavior and grain growth of Ce0.8Gd0.2O1.9 ceramics were investigated with the gallia concentration ranging from 0 to 10 mol%. Both the sintered density and grain size were found to increase rapidly up to 0.5 mol% Ga2O3, and then to decrease with further additions. Under the same sintering conditions, the samples with 3 mol% Ga2O3 and less exhibited a higher sintered density, as compared to the one without Ga2O3 addition. However, a pinning effect on grain growth was found at ≥ 2 mol% Ga2O3. In the dopant content range of 0 to 10 mol%, 0.5 mol% Ga2O3 was the optimum doping level in promoting densification and grain growth of commercially available powders of Ce0.8Gd0.2O1.9.