Numerical study of friction stir welding plunging phase using smoothed particle hydrodynamics

This present study investigates the application of the fully Lagrangian method, smoothed particle hydrodynamics to develop the three-dimensional numerical model for simulation of the friction stir welding (FSW) plunging stage. This method was initially used to model fluid motion due to several benefits over traditional grid-based techniques. Recently, its applications have been expanded to simulate the forming processes. The tool axial force, stress and strain fields during the plunging stage are predicted as characteristics for qualification of a FSW process. Also, the mass scaling technique with two different factors is investigated to find the converged model as well as reduce the CPU time. The developed model is validated by comparing the predicted welding force with experimental values. Two different rotational speed and three stages for plunging depth are also discussed to analyze the influence of the rotational speed and plunging depth on the stress and strain rate.