中文摘要：

以Sm2O3、Gd2O3、Yb2O3和CeO2为原料，采用固相反应法成功制备了具有单一萤石结构的(Sm0.5GdxYb0.5-x)2Ce2O7系列陶瓷材料。所制备材料组织结构致密，晶界清晰。由于基质原子与取代原子之间原子量差随Gd掺杂量增加而逐渐降低，其热导率随Gd掺杂量增加而升高，但均低于Sm2Ce2O7。同时由于Gd和Yb相对较大的电负性，该系列陶瓷热膨胀系数随Gd掺杂量增加而降低，但其热膨胀系数均大于YSZ陶瓷。

英文摘要：

Pure(Sm0.5GdxYb0.5-x)2Ce2O7ceramics with single fluorite-type structure were prepared successfully by solid reaction methodusing Sm2O3,Gd2O3,Yb2O3and CeO2as reactants.The synthesized products has densified microstructure and the grain boundaries are veryclean.Because of the decreasing atomic-weight difference between the substituting and substituted atoms,the thermal conductivity increasegradually with the increasing content of Gd-doping content,and their thermal conductivity is lower than that of Sm2Ce2O7.The thermalexpansion coefficient decreases gradually due to the relatively high electrical-negativity of Gd and Yb,and their thermal expansion coefficientis greater than that of YSZ.