Influence of Re on the Properties of a NiCoCrAlY Coating Alloy

作     者：J.J. Liang H. We Y.L. Zhu X.F. Sun Z.Q. Hu M.S. Dargusch X.D. Yao 

作者机构：Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences Beijing 100039 China School of Materials & Mining Engineering The University of Queensland QLD 4072 Australia 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2011年第27卷第5期

页      面：408-414页

核心收录：

学科分类：0821[工学-纺织科学与工程] 0806[工学-冶金工程] 0817[工学-化学工程与技术] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0703[理学-化学] 0802[工学-机械工程] 082101[工学-纺织工程] 0702[理学-物理学] 0801[工学-力学（可授工学、理学学位）] 

基　　金：supported by the National Basic Research Program ("973 Program") of China under grant No. 2010CB631200 (2010CB631206) the National Natural Science Foundation of China (NSFC) under grantNos. 50931004, 51071164, U1037601 and 50671102 the opening fund of State Key Laboratory of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sciences 

主　　题：NiCoCrAIY Phase constitution Oxidation Thermal expansion behavior Hardness 

摘      要：MCrAIY can serve as stand-alone overlay coatings or bond coats in thermal barrier coating systems, and its properties play a vital role in determining the performance of these coating systems. In order to further understand the behavior of MCrAIY coatings, several NiCoCrAIY model alloys with different levels of Re （0.3 wt%, O wt%, and 9 wt%） were investigated. Microstructural observation showed the addition of Re promoted the precipitation of Cr-rich phases, such as α-Cr and σ. The presence of α-Cr lowered the coefficient of thermal expansion （CTE） of the coating alloys, which could reduce the CTE mismatch at the scale-metal interface. The solid solution strengthening effect of Re is responsible for an increase in Rockwell hardness of the coating alloys. But the isothermal oxidation resistance at 1100℃ was deteriorated due to the precipitation of brittle α-Cr phase, a phase of inferior oxidation resistance compared with β-NiAI and γ-Ni.