Numerical simulations of welding residual stresses in VPTIG-welded joints of the 2219 aluminum alloy
LI Yanjun1, WU Aiping1, LIU Debo2, ZHAO Haiyan1, ZHAO Yue1, WANG Guoqing3
1. Key Laboratory for Advanced Materials Processing Technology of Ministry of Education, State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China;
2. Beijing Institute of Astronautical Systems Engineering, Beijing 100076, China;
3. China Academy of Launch Vehicle Technology, Beijing 100076, China
Abstract：2219 aluminum alloy welded joints have significantly reduced strength because of the softening during welding. The influence of joint softening on the welding residual stress was studied using the thermal elastic plastic finite element method (T-E-P FEM) to predict the welding temperature and residual stresses in a variable polarity tungsten inert gas (VPTIG) welded 2219 aluminum alloy joint. The influences of work hardening and the annealing were also examined. The simulations show that joint softening significantly influences the longitudinal residual stress and that the longitudinal residual stresses in the weld zone and nearby regions are overestimated when the joint softening is not taken into account. Comparison of the simulated results with measured data shows that when work hardening, annealing and joint softening are considered, the residual stresses predicted by the T-E-P FEM agree well with the measured data, which indicates that this approach can accurately predict residual welding stresses in 2219 aluminum alloy.
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