Tensile-Shear Behavior of Steel–Aluminum Spot Joints: A Review

Abstract The increasing demand for lightweight materials in the automotive industry has driven significant advancements in joining technologies for dissimilar materials, particularly steel-aluminum (Fe-Al) assemblies. This study reviews the mechanical behavior of Fe-Al spot joints under tensile shear loading, examining recent joining techniques including resistance spot welding (RSW), rivet welding (RW), friction stir spot welding (FSSW), ultrasonic spot welding (USW), riveting, clinching, and flow drill screwing (FDS). The analysis focuses on key parameters influencing shear performance—such as aluminum sheet thickness, joining area size, and failure mechanisms—while also evaluating the impact of fasteners vs. direct welding, intermetallic compound (IMC) formation. This work could provide a foundation for creating preliminary design abacuses and predictive models to joint behavior in lightweight auto-body assembly.