Dissimilar welding of aluminum to AlSi-coated steel sheets using refill friction stir spot welding: A feasibility study

The main objective of this study was to assess and enhance the weldability of AA60160-T4 to AlSi-coated press-hardened steel (PHS), with a focus on investigating the impact of the AlSi coating on the mechanical properties of welded joints. Variations in tool rotation speed, dwell time, and plunge speed were performed to observe their effects on the joint behavior. It was observed that the protective AlSi-coating significantly influences the mechanical strength of the welded joint. Notably, the removal of the AlSi coating resulted in a substantial increase in joint mechanical strength. To systematically assess joint lap-shear strength under static loading conditions, Design of Experiment technique was employed. The influence of the process parameters on joint strength was thoroughly evaluated.