High cycle fatigue performance at 650℃and corresponding fracture behaviors of GH4169 joint produced by linear friction welding  

作　　者：Shitong MA Xiawei YANG Zhenguo GUO Yu SU Xinyuan HE Ju LI Jun TAO Bo XIAO Wenya LI 

机构地区：[1]State Key Laboratory of Solidification Processing,Shaanxi Key Laboratory of Friction Welding Technologies,School of Materials Science and Engineering,Northwestern Polytechnical University,Xi’an 710072,China [2]Aeronautical Key Laboratory for Welding and Joining Technologies,AVIC Manufacturing Technology Institute,Beijing 100024,China [3]Department of Mechanical Engineering,City University of HongKong,HongKong,China

出　　处：《Chinese Journal of Aeronautics》2025年第1期622-637,共16页中国航空学报(英文版)

基　　金：supported by the National Natural Science Foundation of China(Nos.52074228,52305420,and 51875470);the China Postdoctoral Science Foundation(No.2023M742830)。

摘　　要：GH4169 joints manufactured by Linear Friction Welding(LFW)are subjected to tensile test and stair-case method to evaluate the High Cycle Fatigue(HCF)performance at 650℃.The yield and ultimate tensile strengths are 582 MPa and 820 MPa,respectively.The HCF strength of joint reaches 400 MPa,which is slightly lower than that of Base Metal(BM),indicating reliable quality of this type of joint.The microstructure observation results show that all cracks initiate at the inside of specimens and transfer into deeper region with decrease of external stress,and the crack initiation site is related with microhardness of matrix.The Electron Backscattered Diffraction(EBSD)results of the observed regions with different distances to fracture show that plastic deformation plays a key role in HCF,and the Schmid factor of most grains near fracture exceeds 0.4.In addition,the generation of twins plays a vital role in strain concentration release and coordinating plastic deformation among grains.

关 键 词：High cycle fatigue GH4169 superalloy Linear friction welding Fracture mechanism Microstructure evolution 

分 类 号：V252[一般工业技术—材料科学与工程] V261.34[航空宇航科学与技术—航空宇航制造工程] TG453.9[金属学及工艺—焊接]