3D simulation of FSW to predict distortions
By Marion Geuffrard (ESI group), Hugo Robe (IS group), Joffrey Boursier (Dassault Avialtion), Gilles Surdon (Dassault aviation), Eric Feulvarch (ENISE), Yannick Vincent (esi group)

The simulation of the friction stir welding process involves strong physical coupling between mechanics and heat transfer. In the stirring zone near the pin, the complex material flow induces large deformations and strain rates which must be taken into account in a thermomechanical model. In this study, the Arbitrary Lagrangian Eulerian formulation combined to a moving mesh technique is used to avoid mesh distortion in the stirring zone with a reasonable computation time. The aim of this work is to provide several simulations to analyse the influence of the process parameters. The thermal results obtained by the local simulation are compared to experimental data acquired in various welding combinations (materials, thickness, geometry…).
The second part of this study focused on the prediction of the distortions due to FSW process using a global model. An equivalent thermal heat source calibrated on the local simulation is used. The comparison between the numerical and the experimental distortions after FSW process will be carried out to validate the model. This study is carried out as part of the NOUGAT project(UAF CORAC project).