Simulation of resistance heat aided friction stir welding process

抄録

Resistance heat aided friction stir welding (RFSW) is a new hybrid welding technology which is based on Friction stir welding. This new technology has been invented in order to solve some challenges or questions of friction stir welding. In this paper, a 3D viscoplasticity thermo mechanical model of RFSW with threaded / unthreaded pin is built up, and the temperature, strain-stress, materials flow and welding defects have been achieved successfully by FEM simulation software. The effect of resistance heat is investigated through FSW and RFSW with different magnitudes of additional electronic current. The research results show that additional electronic current reduces the asymmetry of temperature distribution of FSW. RFSW appears as a bimodality strain curve, and the effective strain of the advancing side is larger than that of the retreating side. The threaded pin helps to achieve the material flow in the thickness direction of FSW joints by the tracking method. In addition, the welding defects of kiss, furrow and wormhole are can be predicted successfully. RFSW can make great improvements on the welding defects, which is in agreement with the experimental results.