ZHANG Shaopeng 1, HUA Yinqun 1,2, SHUAI Wenwen 1, JIANG Bochen 2, LI Ruitao 2
(1. Institute for Advanced Material, Jiangsu University, Zhenjiang 212013, Jiangsu, China; 2. School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China)
Abstract: Gd2Zr2O7 and Gd2(CexZr1-x)2O7 (x is 0.1, 0.2, 0.3, respectively) ceramic materials were prepared by high temperature solid state reaction using Gd2O3, ZrO2 and CeO2 as raw materials. The phase composition was analyzed by X-ray diffraction. The microstructure of the material was observed by scanning electron microscopy. The thermal diffusivity and thermal expansion coefficient of the material were measured by laser thermal conductivity meter and high temperature dilatometer. The results show that Gd2Zr2O7 with defective pyrochlore structure and Gd2(CexZr1-x)2O7 (x is 0.1, 0.2, 0.3, respectively) ceramics with fluorite structure are synthesized, and the microstructure is dense and the grain boundaries are clear and clean. The introduction of CeO2 improves the thermal expansion coefficient of Gd2Zr2O7 ceramics and reduces the thermal conductivity of Gd2Zr2O7 ceramics. This allows Gd2(CexZr1-x)2O7 ceramics to be used as a new thermal barrier coating material.
Key words: thermal barrier coating; rare earth zirconate; thermal expansion coefficient; thermal conductivity