采用化学共沉淀-高温煅烧方法制备了0.5xSm2O3-(1-x)CeO2(x=0-1.0)系列陶瓷粉体,并采用XRD方法对其进行了表征.随着x值的增大,陶瓷粉体的结构从单一的萤石结构转变为萤石结构与C-型立方结构共存,最后转变为单斜结构.具有萤石结构的固溶体的晶胞参数随着掺杂量x值的增加而增大,在实验研究基础上建立了计算晶胞参数的经验公式.采用高温原位XRD技术研究了具萤石结构SmxCe1-xO2-0.5x固溶体的晶格热膨胀行为,晶胞参数随着温度的增加而近似线性的增加,室温-1200℃的平均热膨胀系数达到12.5×10-6 K-1.%0.5xSm2O3-(1-x)CeO2 (x = 0-1.0) powders were prepared by reverse coprecipitation-calcination method and characterized by X-ray diffraction. The crystal structure of powders changed from single fluorite structure to the combination of fluorite and C-type cubic structure, then to trigonal structure, with the increase of x-value. An empirical equation simulating the lattice parameter of samarium doped ceria was established based on the experimental data. The lattice thermal expansion behavior of solid solutions with fluorite structure was investigated by the high temperature in-situ X-ray diffraction. The lattice parameters of the solid solutions increased linearly with Sm3+ content and heating temperatures increasing. The average thermal expansion coefficients of samarium doped ceria with fluorite structure were higher than 12.5×10-6 ℃-1 at room temperature to 1200 ℃.
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