Investigations on the Effect of Various Tool Pin Profiles in Friction Stir Welding Using Finite Element Simulations

Abstract

Friction stir welding (FSW) is a solid state joining process which uses a rotating tool consisting of a shoulder and a pin/probe. The shoulder applies a downward pressure to the work piece surface, generates heat through the friction and leads to plasticization of materials in the vicinity of pin. During traverse the rotating tool mixes the adjacent material in the stir zone, creating a joint without fusion. The welding tool pin profile plays a major role in obtaining desirable weld. At present, research efforts are being made to gain a better understanding of the process, to explore different tool configurations, to optimize the set of process parameters and to widen the applicability of FSW and it variants. In this regard, having reliable finite element model that is capable of simulating FSW with minimal possible simulation time can turn out handy to reduce the number of physical experiments required in such studies and applications. The current work investigates a model based approach in knowing the effect of various tool pin profiles on temperature, stir zone and power consumed for welding. A three-dimensional (3-D) model is developed in finite element (FE) commercial code ABAQUS/Explicit using the Coupled Eulerian-Lagrangian (CEL) formulation, the Johnson-Cook material law and Coulomb's law of friction. The obtained results help in arriving at better tool designs.