Thermo-Mechanical Simulation of Temperature Distribution and Prediction of Heat-Affected Zone Size in MIG Welding Process on Aluminium Alloy EN AW 6082-T6

Welding process is considered as a thermal-mechanical-metallurgical coupled problem. In this study, finite element method (FEM) is adopted for predicting the temperature history in Metal Inert Gas (MIG) welding of 5mm thick aluminium 6082 alloy. The Goldak's double ellipsoidal moving heat source model was used to analyse the influence of peak temperature to the radial distance from the center of the heat source and the thickness of the plate. Temperature-dependent thermal properties of aluminium alloy 6082 in T6 condition and the convective and radiative boundary conditions were included in the model. The finite element code, ANSYS along with APDL command subroutines was employed to obtain the numerical results. The effect of heat input and welding speed on the weld pool shape and temperature distribution were investigated. Finally, the predicted temperature distribution and the size of heat-affected zone were compared with the experimental results. The comparison shows that they are in good agreement.