Powder morphology modification and sinterability improvement of Ce0.8Sm0.2O1.9 derived from solution combustion process

Ce0.8Sm0.2O1.9 powders were synthesized by solution combustion process using a relatively low fuel (urea) concentration. The morphology of the powders was studied in relation to the synthetic process. The sinterability and microstructure of the ceramic specimens were investigated with respect to the powder morphology. The as-combusted powder showed sphere-like fine particles constituted by an aggregation of Ce0.8Sm0.2O1.9 nanocrystallites. A ball-milling process modified the morphology of the powder and improved the sinterability of the ceramic specimens. The fuel concentration of the combustion synthetic system played an important role in determining the morphology and the sintering reactivity of the resulting powders. The microstructure evolution of the ceramic specimens with sintering temperature was found to be closely related with the powder morphology. Ce0.8Sm0.2O1.9 ceramics with high relative densities (95.8-98.0%) and fine grains (0.2-0.3 μm) were prepared from the ball-milled powder at relatively low sintering temperatures of 1100-1200 °C.