Interfacial coherence regulation and stabilization of molybdenum/Kovar alloy welded joint by CoCrCuFeNi high entropy alloy  

作　　者：Qianxing Yin Guoqing Chen Xinyan Teng Yang Xiang Xuesong Leng 

机构地区：[1]State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Harbin 150001,China [2]Beijing Shiny Technology Co.Ltd.,Beijing 100089,China [3]State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Shenzhen 518055,China

出　　处：《Journal of Materials Science & Technology》2024年第27期43-50,共8页材料科学技术(英文版)

基　　金：supported by the National Natural Science Foundation of China(Grant No.52375322);the Key Special Projects of Aeroengine and Gas Turbine(Grant No.J2019-VII-0012-0154).

摘　　要：The crux of molybdenum/Fe-base alloy welded joint is embrittlement and consequently deteriorated strength.The current researches just attribute it to brittle intermetallic compound inside the weld.However,no brittle phase continuously precipitates at the fracture location of the molybdenum/Kovar alloy electron beam welded joint,meaning that the unstable phase interface is the real fundamental reason for the brittleness of joint,instead of the phases themselves.Noncoherent interfaces are formed betweenα-Mo and eutectoidα-Fe+μ(Fe3Mo2)deriving from solid-state phase transition.To optimize interfacial coherence and stabilize the interface,CoCrCuFeNi high entropy alloy is added into the weld.The new interfaces betweenα-Mo and eutectic face-centered cubic(fcc)+laves are transformed into coherent interfaces.σ(FeCr)nanoparticles precipitate atα-Mo/fcc interface,indicating the decreased interfacial energy and more stable interface.The tensile strength of the joint is increased from 262 to 366 MPa.The present work provides guidance for optimizing welding quality between molybdenum and Fe-base alloy.

关 键 词：Electron beam welding MOLYBDENUM High entropy alloy Interfacial stabilization Nano-scale particle 

分 类 号：TG1[金属学及工艺—金属学]