Experimental and numerical investigation of the plunge stage in friction stir welding

A better understanding of the plunge phase is critical with the growing role of friction stir spot welding and also in understanding tool wear in case of friction stir welding (FSW) of high strength alloys. This paper investigates the plunge stage using experimental and numerical modeling. Plunge experiments were performed on aluminum 2024 alloy with simultaneous measurement of temperature and axial loads. Specimens were examined using energy dispersive spectroscopy (EDS) for wear particles from the tool. A 3D finite element-based model (FEM) of the plunge stage was developed using the commercial code ABAQUS to study the thermomechanical processes involved during the plunge stage. The strain rate and temperature-dependent Johnson–Cook material law is adopted in the FEM. The numerical simulation data correlate well with the experimental data obtained in this research as well as to experimental data from the literature.