Simulation of friction stir welding using thermo-mechanical coupled finite element method

Abstract

Friction stir welding (FSW) is a solid-state welding process for joining of two metals where the heat is generated from the mechanical friction between the work materials and a rotating tool. Also, additional heat is generated by plastic deformation of the workpiece material. In this paper, the process involved in this technique of welding without using any filler metal is simulated using ANSYS ® parametric design language. A thermo mechanical coupled model is developed to analyze the thermal and mechanical responses during the welding process. The method of direct coupling is applied by using SOLID 226 thermo-mechanical coupled element. Unlike the sequential 1-way coupling method where the result from thermal analysis is used as input data for structural model, direct coupling solves both the thermal and mechanical boundary conditions simultaneously for the coupled model. Coupled analyses are more computationally intensive. Usually, physics of coupling is ignored or simplified but a coupled analysis provides more realistic results.