Friction Stir Welding Process Parameter Effects on Workpiece Warpage due to Residual Strains

An important performance measure of the quality of a weld is the permanent deformation developed during welding processes due to the thermally activated residual strains. This paper presents the results of a sensitivity analysis that determines the effects of processing parameters — such as the speed of rotation and the traveling speed of a rotating friction stir welding (FSW) tool — on the resulting residual strain fields. The problem has been modeled as a thermostructurally coupled problem via Finite Element Analysis of an elastoplastic workpiece under the influence of heat generated from the stirring process and taking into account the temperature dependent yield strength of the material. Results are presented and discussed in the context of our future plans.