Robust interfacial bonding achieved via phase separation induced by enhanced Al diffusion during AZ31/high-entropy alloy friction stir welding  

作　　者：Gaohui Li Haining Yao Boyuan Fu Ke Chen Katsuyoshi Kondoh Nannan Chen Min Wang 

机构地区：[1]School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China [2]Shanghai Key Laboratory of Materials Laser Processing and Modification,Shanghai Jiao Tong University,Shanghai 200240,China [3]Joining and Welding Research Institute,Osaka University,Ibaraki,Osaka 567-0047,Japan

出　　处：《Journal of Magnesium and Alloys》2025年第3期1012-1019,共8页镁合金学报(英文)

基　　金：supported by the National Natural Science Foundation of China[Grant numbers:52475385,52305392];the China Postdoctoral Science Foundation(Grant No.2022M722048).

摘　　要：Welding high-entropy alloy(HEA)to Mg alloy has gained increasing attention for multi-metal structure design,while intrinsic sluggish diffusion kinetics of HEA confines diffusion-controlled interfacial reactions and makes it challenging to establish robust metallurgical bonding.This study investigated welding of FeCoCrNiMn HEA to commercial AZ31 as a model combination to pioneer thisfield.Interfacial phase separation phenomenon was observed,with the diffusion accelerated by in-situ engineering a submicron-scale thick(∼400–500 nm)HEA nearby the interface into nanocrystalline-structure during friction stir welding.Abundant grain boundaries generated in this nanocrystalline-interlayer serve as diffusion short-circuits and energetically preferred nucleation-sites,which promoted Al in AZ31 to diffuse into HEA and triggered quick separation into body-centered cubic AlNi-type and tetragonal FeCr-type intermetallics.HEA and AZ31 were thus metallurgically bonded by these interfacial intermetallics.The joint shows exceptional strength in tensile lap-shear testing with fracture largely occurred within AZ31 rather than right along interface as commonly reported previously for dissimilar joints.

关 键 词：High-entropy alloy Mg alloy Friction stir welding DIFFUSION Phase separation 

分 类 号：TG457.1[金属学及工艺—焊接]