Fully coupled thermo-mechanical modelling of the initial phase of the Friction Stir Welding Process using Finite Element Analysis

Abstract

In the present study a finite element model of the FSW process is built and a FSW butt weld of two aluminium alloy 2024-T3 plates is simulated using a fully coupled thermo-mechanical analysis. Besides the welded panels, the model includes the backing plate and the welding tool as physical bodies, which makes the simulations more realistic. The model also includes conductive heat transfer between the contact surfaces of the FSW tool, the aluminium plates and the backing plates, heat generation due to friction between the tool and the welded plates and heat loss to the ambient air due to convection.The simulated model makes it possible to analyse and check several aspects of this welding technique. It is proved that tool geometry has a vital importance in the FSW process. The influence of using instantaneous or ramped velocity at the beginning of the simulations is also studied. Moreover, it is seen that the mesh used in the finite element analysis and the adjustment of the inelastic heat fraction have a great influence on the obtained results.