Trade-off Analysis of Alternative Numerical Modelling Approaches for Distortion and Stress Field Prediction in Submerged Arc Welding Process

Numerical simulations of welding processes, although a quite complex modelling and calibration is required, can be a powerful tool to reduce both design time and costs ascribable to experimental tests. Indeed, numerical simulations allow prediction of distortions and residual stresses on welded joints related to the thermal process effects. This paper focuses on a numerical modelling and simulation of a multi-pass submerged arc welding process performed on a butt joint configuration of A516 steel plates with different thicknesses. The numerical analysis was performed by using the software package ESI SYSWELD. This software simulates welding processes by three different methods, depending on the objectives to be reached, i.e. the moving heat source, the macro-bead and the shrinkage methods. These methods differ mainly in the thermo-mechanical data of the material provided as inputs for the model definition and, consequently, for the considered physical phenomena. Herein, these three different approaches were implemented for the specific process configuration. The obtained results were compared providing a wide overview of the most suitable numerical strategies evaluating the distortions and the residual stresses induced in the investigated joined parts. The methods’ comparison includes also considerations on computational times required to perform the analysis.