Study on 2219 Al-Cu alloy T-joint used dual laser beam bilateral synchronous welding: Parameters optimization based on the simulation of temperature field and residual stress

Abstract

In the current research, the dual laser beam bilateral synchronous welding (DLBSW) of 2219 Al-Cu alloy T-joint is investigated by finite element (FE) simulation of temperature field and residual stress, which aims at the optimization of the welding process parameters. The FE mesh model of the T-joint is established by simplifying the equal boss of the skin. The combined Gaussian laser heat source is adopted to simulate the laser energy loaded on the Al-Cu alloy during welding process. Furthermore, a test table of process parameters with the laser power and welding speed is designed to investigate the parameters via the simulation results. The simulation with 16 groups of parameters are performed based on the heat source model which is checked by the experimental result. Two cases of parameters are filtered from the simulation results for the hoop tensile test experiment. It is employed to estimate the tensile and yield strength of the T-joints with the filtered parameters. Welding process parameters in case 6, which are the laser power of 4300 W and welding speed of 2.5 m/min, are the optimized parameters in the test table based on the tensile strength (337.28 MPa) and yield strength (243.51 MPa) obtained by the tensile test results.