An efficient strategy for 3D numerical simulation of friction stir welding process of pure copper plates

Copper and its alloys have a wide spectrum of engineering applications such as heat exchangers, hot water tanks or nuclear pressure vessels. Most of these structures are obtained by welding. Unfortunately, the use of conventional arc welding process is affected by several factors such as the thermal conductivity of the alloy being welded, the shielding gas, the joint design, the welding position, and the surface condition and its cleanliness. Friction stir welding process could be an interesting alternative as it can be performed without melting the material, it involves a non-consumable tool, and provides good mechanical properties. To understand in depth both the physical and the thermal mechanisms involved in this process, numerical modelling is essential. The aim of this paper is to propose an efficient simulation strategy based on the coupled Eulerian Lagrangian finite element method. The mass scaling procedure, which is used to decrease the computation time will be presented, as well as its effect on the temperature field distribution and on the down force. This model will then be used for a parametric study in order to improve the friction welding process's parameters.