SmGdCe_2O_7陶瓷材料的热膨胀系数及热导率  

Thermal Expansion Coefficient and Thermal Conductivity of SmGdCe_2O_7 Ceramic Materials

作　　者：杨树森[1] 陈晓鸽[2] 温倩[3] 张红松[3] 

机构地区：[1]铁道警察学院,河南郑州450053 [2]河南工程学院土木程学院,河南郑州451191 [3]河南工程学院机械工程学院,河南郑州451191

出　　处：《热加工工艺》2015年第2期121-124,127,共5页Hot Working Technology

摘　　要：以Sm2O3、Gd2O3和Ce O2为原材料,采用固相反应法制备了Sm Gd Ce2O7陶瓷材料,用X射线衍射分析了其相结构,采用扫描电镜(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Sm Gd Ce2O7具有典型的萤石结构,其微观组织致密,晶界清晰。Gd3+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的陶瓷层材料。SmGdCe207 ceramic was synthesized by solid reaction method by using Sm203, Gd203 and CeO2 as raw materials. The phase-structure was analyzed by XRD, the microstructure and element composition of the samples were examined by SEM and EDS. The thermal expansion coefficient and thermal conductivity were investigated by pushing-rod method and laser-flash method, respectively. The results show that the synthesized SmGdCe2O7 ceramic has a typical fluorite structure; the microstructure is very dense. The lower radius of Gd3＋ ion leadto its lower thermal expansion coefficient compared with Sm2Ce2O7. Differences in mass and ionic radius between Sm3＋ ion and Gd^＋3＋ ion can result in the lower thermal conductivity of SmGdCe2O7 compared with Sm2Ce2O7. The synthesized SmGdCe207 can be used as candidate material for ceramic-layer in new thermal barrier coatings.

关 键 词：热障涂层 稀土铈酸盐 热物理性能 声子散射 

分 类 号：TG113.223[金属学及工艺—物理冶金]