Thermomechanical analysis for Laser plus GMAW-P hybrid welding process

A three-dimensional transient model is developed for numerical analysis of the coupled heat conduction and residual stress and distortion phenomena in laser beam welding plus pulsed gas metal arc welding (GMAW-P) hybrid process. Based on an adaptive combined volumetric heat source model, the transient temperature field is computed, and then the thermal analysis data are utilized as input of subsequent thermomechanical analysis. The residual stress distributions of test plates are calculated for both GMAW-P and Laser + GMAW-P hybrid welding processes. Experiments are made to measure weld dimensions and residual stresses. The weld residual stress distributions of GMAW-P and Laser + GMAW-P hybrid welding are compared under the conditions of the nearly same weld penetrations. The predicted results of the weld shapes and residual stresses are in agreement with the experimental measurements. The simulated results show that the residual stresses and distortion of test plates made by Laser + GMAW-P hybrid welding is lower than those by GMAW-P. (C) 2009 Elsevier B.V. All rights reserved.