High entropy defective fluorite structured rare-earth niobates and tantalates for thermal barrier applications  

作　　者：Zifan ZHAO Heng CHEN Huimin XIANG Fu-Zhi DAI Xiaohui WANG Wei XU Kuang SUN Zhjjian PENG Yanchun ZHOU 

机构地区：[1]Science and Technology on Advanced Functional Composite Laboratory,Aerospace Research Institute of Materials&Processing Technology,Beijing 100076,China [2]School of Engineering and Technology,China University of Geosciences,Bejing 100083,China [3]Shenyang National Laboratory for Materials Science,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China [4]Shanghai Chenhua Science and Technology Corporation Ltd.,Shanghai 201804,China

出　　处：《Journal of Advanced Ceramics》2020年第3期303-311,共9页先进陶瓷（英文）

基　　金：This study was financially supported by the National Natural Science Foundation of China(Nos.51672064 and 51972089).

摘　　要：Rare-earth tantalates and niobates(REjTaO7 and REjNbO7)have been considered as promising candidate thermal barrier coating(TBC)materials in next generation gas-turbine engines due to their ultra-low thermal conductivity and better thermal stability than yttria-stabilized zirconia(YSZ).However,the low Vickers hardness and toughness are the main shortcomings of RE;TaO-and REjNbOr that limit their applications as TBC materials.To increase the hardness,high entropy(Yu3Ybu3Er/3)sTaOr,(Y13YbnErns)NbO,and(Sm1/6Eu1/6Y 1/6Yb1/6Lu1/6Er1/6)3(Nb1/2Ta1/2)O7 are designed and synthesized in this study.These high entropy ceramics exhibit high Vickers hardness(10.912.0 GPa),close thermal expansion coefficients to that of single-principal-component RE3TaO,and RE;NbO,(7.9×10^-6-10.8×10-6 C-1 at room temperature),good phase stability,and good chemical compatibility with thermally grown Al2O3,which make them promising for applications as candidate TBC materials.

关 键 词：high entropy ceramics defective fluorite structure rare-earth niobates/tantalates thermal barrier coating material 

分 类 号：TG174.4[金属学及工艺—金属表面处理]