Numerical Simulation Investigation on Split Sleeve Cold Expansion of Ti-Al Stacked Structure  

作　　者：GAo Yue LU Shihong FU Jingyi 

机构地区：[1]College of Mechanical and Electrical Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2023年第5期1147-1154,共8页武汉理工大学学报（材料科学英文版）

基　　金：Funded by National Natural Science Foundation of China(No.51175257)。

摘　　要：Split sleeve cold expansion(SSCX)can efiectively enhance fatigue life of holes by improving the field of residual stress.Numerical simulations were conducted to investigate the parameter influence mechanism and obtain higher compressive residual stress(CRS).Expansion method,degree of cold expansion(DCE),friction coefficient between laminations and depth-diameter ratio were analyzed.For Ti-Al stacked joint holes,two expansion methods are proposed,namely aluminum alloy first followed titanium alloy(Al first)and titanium alloy first followed aluminum alloy(Ti first).The results show that expansion method and DCE have significant efiects on the field of circumferential residual stress,and the friction has a negligible influence.A higher value of CRS and a wider layer of plastic deformation are induced with Ti first.Optimal DCE of TiAl stacked structure is 5.2%-5.6%.As the depth-diameter ratio is in the range of 0.5-1.25,a positive linear correlation between the maximum compressive residual stress(CRS_(max))and depth-diameter ratio is shown.

关 键 词：Ti-Al stacked structure SSCX residual stress expansion method DCE 

分 类 号：TG1[金属学及工艺—金属学]