(Sm_(0.7)Yb_(0.3))_2Ce_2O_7陶瓷的热膨胀系数及热导率  

Thermal Expansion Coefficient and Thermal Conductivity of( Sm_(0.7)Yb_(0.3))_2Ce_2O_7 Ceramic Materials

作　　者：马建辉[1] 郭鹏[1] 张红松[1] 

机构地区：[1]河南工程学院机械工程学院,郑州451191

出　　处：《硅酸盐通报》2014年第8期2133-2137,共5页Bulletin of the Chinese Ceramic Society

摘　　要：以Sm2O3、Yb2O3和CeO2为原材料,采用固相反应法制备了(Sm0.7Yb0.3)2Ce2O7陶瓷材料,用X射线衍射(XRD分析了其相结构,采用扫描电子显微镜(SEM)和电子能谱(EDS)分析其显微组织和元素组成,用推杆膨胀法和激光脉冲法测试了其热膨胀系数和热导率。结果表明,所制备的(Sm0.7Yb0.3)2Ce2O7具有典型的萤石结构,其微观组织致密,晶界清晰。Yb3+离子较小的离子半径使其热膨胀系数低于Sm2Ce2O7,基质原子与取代原子之间质量及尺寸之间的差别,使其具有比Sm2Ce2O7更低的热导率,该材料有潜力用作新型热障涂层表面陶瓷层材料。The （Sm0.7 Yb0.3 ）2Ce207 ceramic was synthesized by solid reaction method using Sm203, Yb203 and CeO2 as raw materials. Its phase-structure was analyzed by X-ray diffraetion （XRD）, the microstructure and elemental composition were examined by seanning electrical microscope （SEM） and electronic diffraction spectrum （EDS）. Its thermal expansion coefficient and thermal conductivity were investigated by pushing-rod method and laser-flash method, respectively. Results show that the synthesized （Sm0.7 Yb0. 3 ） 2 Ce2 O7 ceramic has a typical fluorite structure ; its microstructure is very dense. The lower radius of Yb^3＋ ion leads to its lower thermal expansion coefficient as compared to SmECezO7, grain boundary clear. Differences in mass and ionic radius between substrate atoms and substitution Atom result in the lower thermal conductivity of （Sm0.7 Yb0.3 ）2Ce2O7 as compared to Sm2Ce207. The synthesized （Sin0.7 Yb0.3 ）2Ce2O7 earl be used as candidate material for ceramic-layer in new thermal barrier coatinas.

关 键 词：热障涂层 稀土铈酸盐 热膨胀系数 热导率 

分 类 号：TQ174[化学工程—陶瓷工业]