Microstructural stability and aging behavior of refractory high entropy alloys at intermediate temperatures  

作　　者：P.P.Cao H.L.Huang S.H.Jiang X.J.Liu H.Wang Y.Wu Z.P.Lu 

机构地区：[1]Beijing Advanced Innovation Center for Materials Genome Engineering,State Key Laboratory for Advanced Metals and Materials,University of Science and Technology Beijing,Beijing 100083,China

出　　处：《Journal of Materials Science & Technology》2022年第27期243-254,共12页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.11790293,51871016,51671021,51971017,51921001);111 Project(No.B07003);the Program for Changjiang Scholars and Innovative Research Team in University of China(No.IRT_14R05);the financial support from the National Key Basic Research Program,China(No.2016YFB0300502)。

摘　　要：Several body-centered-cubic(BCC)refractory high entropy alloys(HEAs),i.e.,Hf Nb Ta Ti Zr,Nb Ta Ti Zr,Hf Nb Ti Zr and Nb Ti Zr,were annealed at intermediate temperatures for 100 h,and their microstructures and aging behaviors were studied in detail.All these HEAs start to decompose into multiple phases at around 500°C,but reenter the single-phase region at significantly different temperatures which were determined to be 900,1000,1100 and above 1300°C for Hf Nb Ti Zr,Nb Ti Zr,Hf Nb Ta Ti Zr and Nb Ta Ti Zr,respectively.Our analysis indicates that the onset decomposition temperature in these four HEAs is closely related to the elemental diffusion rates while the ending decomposition temperature is strongly dependent on the elemental melting points.Our findings are important not only for understanding phase stability of HEAs in general,but also for adjusting processing parameters to optimize mechanical properties of these HEAs.

关 键 词：Refractory high entropy alloys Phase decomposition Diffusion rate Melting point 

分 类 号：TG139[一般工业技术—材料科学与工程]