Finite Element Simulation of the Residual Stresses in Butt Weld Plate of Aluminum Alloy

Finite element simulation is utilized in an aluminum alloy 2014 butt weld with the three kinds of welding processes, namely the filler wire Tungsten Inert Gas (TIG) welding, the laser welding and laser-TIG hybrid welding. The simulated results are in good agreement with the weld cross sections for the TIG and the laser welding, and basically in agreement with that for the laser-TG hybrid welding using the actual welding parameters. Furthermore, the simulated results shown that the longitudinal residual stresses after welding are the largest for the laser welding and the laser-TIG hybrid welding, the maximum of which are approximate to 300MPa and are 1.2 times of that for the TIG welding. However, the residual stresses would be relatively decreased by backing molten with TIG welding and preheating before welding; the maximum longitudinal residual stresses for the laser welding and the laser-TIG hybrid welding could be decreased remarkably by about 50%.