The effect of temperature alternating load on residual stresses for Al-Li alloy T-joints welded by dual laser beam bilateral synchronous welding

The finite element (FE) simulation is employed to predict the residual stresses, which is induced by the welding and the temperature alternating load. The simulation of 5A90 Al-Li alloy T-joint welded by the dual laser beam bilateral synchronous welding (DLBSW) is carried out. Then the evolution of the residual stresses is obtained under the temperature alternating load which is achieved by changing the ambient temperature on T-joint. In addition, the accuracy of simulation model has been verified by comparing the experimental results with the simulation results. According to the comparison, the simulation results are consistent with the experimental results, which shows that the residual stresses of 5A90 T-joints decrease under the temperature alternating load. Besides, the FE simulation is a relatively efficient and accurate method to predict the change of residual stresses under the temperature alternating load.