Simulation of a Refill Friction Stir Spot Welding Process Using a Fully Coupled Thermo-Mechanical FEM Model

摘要

Friction stir spot welding (FSSW) is a solid state joining technol-ogy that has the potential to be a replacement for processes like resistance spot welding and rivet technology in certain applica-tions. To optimize the process parameters and to develop FSSW tools, it is important to understand the physics of this complex process that involves frictional contact, high temperature gradi-ents, and large deformations. This paper presents a fully coupled thermo-mechanical finite element model (FEM) model of the plunge phase of a modified refill FSSW. The model was developed in Abaqus/Explicit and the simulation results included the tem-perature, deformation, stress, and strain distributions in the plates being joined. An experimental study was also conducted to vali-date the temperatures predicted by the model. The simulation re-sults were in good agreement with the temperatures measured in the experiment. Also, the model was able to predict in a reason-able fashion the stresses and plastic strains in the plates.