FE modelling of friction stir welding process of dissimilar aluminium alloys using coupled Eulerian-Lagrangian (CEL) approach

Friction stir welding (FSW) is increasingly used as joining technology because of its ability to weld dissimilar metals and thus providing great potential of lightweight design. To obtain appropriate welding parameters for the FSW process, which lead to joints with high load carrying performance, is still a massive challenge and is often more time-consuming or needs costly experimental investigations. Therefore, in this work FE simulations of FSW of different aluminium grades were performed using coupled Eulerian-Lagrangian (CEL) approach. Hereby, temperature-dependent thermo-mechanical properties were applied in combination with the Johnson-Cook plasticity model for both examined alloys. First, numerical results were validated by comparing local temperature distributions with measured experimental data. Subsequently, size of various weld zones, local deformation and defects were evaluated with respect to used welding parameters such as welding speed and rotational speed. The developed FE model could be employed to find proper FSW parameters for any certain applications.