Finite element modelling of transient behaviours and microstructural evolution during dissimilar rotary friction welding of 316 austenitic stainless steel to A516 ferritic steel

Inertia friction welding (IFW) is a near-net-shape joining process that produces high-integrity welds. The transient nature of this joining process necessitates the availability of reliable computational models to predict the evolution of temperature and deformation throughout welding. In this study, a thermo-mechanical finite element (FE) model, based on an adaptive remeshing technique, is proposed to simulate dissimilar joining of A516 ferritic steel and 316L austenitic stainless steel (SS). The results of FE model were evaluated and verified via comparing the shape/size of the flash, upsetting load and angular velocity profile of a physical weld produced by IFW trials. A good agreement was achieved between the appearance of the weld/flash and those predicted by the FE model, thus verifying the predicted temperature and strain distributions. The microstructural features across different weld regimes were also examined to correlate the concomitant changes with the simulated temperature profile.