Prediction of weld geometry, temperature contour and strain distribution in disk laser welding of dissimilar joining between copper & 304 stainless steel

In this study, a simulation is developed for dissimilar metal sheets followed by a mathematical model for laser welding. The continuous disk laser welding process for dissimilar joining between 304 stainless steel and copper is simulated. For this purpose, six different heat flux distribution models are implemented into Abaqus/Standard solver using additional DFLUX subroutine written in the FORTRAN programming language. By estimating the temperature distribution, prediction of the geometry and dimensions of weld cross section including the fusion zone (FZ) and heat affected zone (HAZ), a heat source model was suggested for finite element modelling of the dissimilar keyhole laser welding process for joining 304 stainless steel and copper sheets with 20 x 15 x 2 mm dimensions by butt joint. The weld joint output parameters such as temperature, strain distribution and weld geometry were examined. The results showed that copper, due to the higher thermal conductivity during cooling, passed through more heat at the same period of time, so these results lead to lower temperature in the center of FZ and a smaller HAZ in this dissimilar welding in comparison to similar welding. The validation of the simulation results, including the temperature distribution, weld cross section geometry, dimensions of FZ and HAZ, was confirmed by comparison with the experimental results reported by other researchers. The computed results are well agreed with experimentally measured values and show the robustness of the present numerical model used for dissimilar laser welding.