High-Temperature Fatigue Behavior of Inertia Friction Welded Joints of GH4065A Ni-Based Superalloy  

作　　者：Xiaoguang Li Jiatao Liu Qing Liu Chunbo Zhang Hang Liang Lei Cui Yongchang Liu 

机构地区：[1]School of Materials Science and Engineering,Tianjin University,Tianjin,300072,China [2]AECC Shenyang Liming Aero-Engine Co.,Ltd,Shenyang,110043,China [3]Harbin Welding Institute Co.,Ltd,Harbin,150028,China [4]Tianjin Key Laboratory of Advanced Joining Technology,Tianjin,300072,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2024年第11期1935-1946,共12页金属学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.52322408,52305407);the Science and Technology Program of Tianjin(23JCQNJC01990);the independent Innovation Fund of Tianjin University(2024XQM-0013).

摘　　要：In this work,the novel Ni-based superalloy GH4065A inertia friction welding(IFW)joints were subjected to the post-welding heat treatments(PWHT)at 730℃for 5 h or 760℃for 5 h,and the differences in microstructure characteristics,local mechanical properties,and fatigue failure life were focused.Furthermore,based on the high-temperature low-cycle fatigue testing and characterization results,the correlation between the microstructure characteristics and low-cycle fatigue damage behavior was systematically analyzed.It was found that there were smaller grains in the thermo-mechanically affected zone(TMAZ)than in the weld zone and heat-affected zone(HAZ),and the boundary region between TMAZ and HAZ was the fatigue failure position of IFW joints under the high-temperature low-cycle fatigue loading.The fatigue testing results showed that the high-temperature fatigue performance for GH4065A IFW joints degenerated with the increase in PWHT temperature.There existed cyclic softening and inhomogeneous fatigue damage in an IFW joint,which was more significant under the 760℃5 h PWHT condition.Microstructurally,dislocation tangles and cells formed in the boundary region between TMAZ and HAZ under the fatigue loading.The difference in grain size after the IFW process and the inhomogeneousγ′phrase re-precipitation after the PWHT in the boundary region between TMAZ and HAZ resulted in the local inhomogeneous strengthening,corresponding to uneven plastic deformation and fatigue failure behavior under the fatigue loadings.

关 键 词：Inertia friction welding GH4065A alloy Low-cycle fatigue Post-welding heat treatment Fatigue behavior 

分 类 号：TG407[金属学及工艺—焊接]