Influence of Plunge Depth on Temperatures and Material Flow Behavior in Refill Friction Stir Spot Welding of Thin AA7075-T6 Sheets: A Numerical Study

Plunge depth is one of the most important process parameters that affect joint strength in refill friction stir spot welding (refill FSSW). In this study, a three-dimensional numerical model developed using Lagrangian incremental formulation DEFORM-3D to simulate FSSW thin AA7075-T6 sheets. The verified by comparing obtained temperatures at specific locations with from previous experimental studies. Material flow and temperature behaviors three different plunge depths are analyzed model. effective strains weld zone increased an increase depth. movement material enhanced larger extent bottom sheet involved stirring width thickness identified consistent study literature. decrease reported literature correlated behavior models.