Numerical simulation of friction stir welding process

Thermo-mechanical simulations of the friction stir butt welding and friction stir spot welding processes were performed for AA5083-H18 sheets, utilizing commercial FVM codes which are based on the Eulerian formulation. For the friction stir butt welding process, the computational fluid dynamics code, STAR-CCM+, was utilized under the steady state condition. Temperature and strain rate histories along the material flow were calculated and simulated temperature distributions (profiles and peak values) were compared with experiments for verification. It was found that by including proper thermal properties of the backing plate (anvil) the accuracy of the simulation results increased significantly. For the friction stir spot welding process, the computational fluid dynamics code, STAR-CD, was utilized under the unsteady condition to understand the effect of pin geometry on material flow and weld strength.