中文摘要：

以硝酸盐做氧化剂，柠檬酸为燃料，采用低温燃烧法制备纳米级超细Ce0.8Y0.2O1.9（YDC）固溶体。利用TG—DSC，XRD，SEM，FT-IR和BET等手段对凝胶前驱体的热分解行为、相转化过程和YDC粉体的性能进行表征。TG—DSC结果表明，柠檬酸一硝酸盐干凝胶的点火温度约为263．3℃；经XRD测试，粉体经600℃焙烧即形成了单相立方萤石型结构的固溶体，晶粒度为16～23nm。柠檬酸与硝酸盐摩尔比（CA／N）对粉体的微观形貌、比表面积和烧结活性有显著影响。当CA／N为1．5：1时，粉体粒子间仅有微弱的软团聚，将素坯在1400℃烧结2h，得到相对密度为95．6％，平均粒径约为0．7μm的陶瓷烧结体。

英文摘要：

The ultrallne Ce0.8Y0.2O1.9solid solutions were prepared via low temperature combustion synthesis using nitrate as oxidant and citric acid as fuel. The products were characterized by TG-DSC, XRD, SEM, FT-IR and BET method, respectively, and the evolution behavior of the gel precursor, phase translation and properties of YDC powders were investigated. The TG-DSC results showed that the igniting temperature of citric acid-nitrate mixture gel was about 263. 3 ℃. The XRD results showed that YDC powders calcined at 600 ℃ with crystallites in 16 - 23 nm ranges had a single cubic fluorite-type structure. It was found that the molar ratio of citric acid to nitrate had great effect on the morphology, the specific surface area and the sinterability of the powders. When the molar ratio of citric acid to nitrate was 1.5： 1, the YDC powders possessed weakly aggregated. The powders had good sinterability in the experiment and the sintered specimens with relative density of 95.6% could be manufactured at 1400 ℃ for 2 h under simply processing conditions. The average grain size was 0.7 μm for the sintered specimens.