中文摘要：

以Gd2O3、MgO和Ce（NO3）.6H2O为原料,采用溶胶凝胶法制备了（Gd1-xMgx）2Ce2O7-x/2固溶体。用X射线衍射法分析了固溶体的相组成,用扫描电镜观察了其致密块体样品的显微组织,用激光脉冲法测试了固溶体的热扩散系数。结果表明,成功制备了纯净的具有萤石结构的（Gd1-xMgx）2Ce2O7-x/2固溶体,其致密块体结构致密,晶界清晰,较多的氧空位使（Gd0.95Mg0.05）2Ce2O6.95具有最低的热导率,（Gd1-xMgx）2Ce2O7-x/2固溶体有潜力用作热障涂层表面陶瓷层材料。

英文摘要：

Using Gd2O3 ,MgO and Ce（NO3 ）·6H2O as reactants,（Gd1-xMgx ）2Ce2O7-x/2 solid solutions were prepared by Sol-gel method.Their phase structure was analyzed by X-diffraction,their microstructure was ob-served by scanning electronic microscope,and their thermal diffusivities were measured by laser-flashing meth-od.Results show that pure （Gd1-xMgx ）2Ce2O7-x/2 ceramics with fluorite structure are synthesized successfully, the dense bulk samples have dense microstructure and clean grain boundaries.The new produced oxygen vacan-cies results in the lowest thermal conductivity of （Gd0.95Mg0.05 ）2Ce2O6.95 solid solution.The （Gd1-xMgx ）2Ce2O7-x/2 solid solutions can be used as ceramic materials for thermal barrier coatings.