Abstract Scope |
The implementation of lightweight materials and structures in automotive body manufacturing is a strategic approach to improve fuel efficiency of energy-efficient vehicles and driving range of new energy vehicles. However, high specific strength low-ductility light metals (like 7xxx aluminum, magnesium and cast aluminum), ultra-high strength steels, high-stiffness profile structures and their mixed use poses a big challenge to existing commercial spot joining processes, such as resistance spot welding and self-piercing riveting. In this talk, the challenges which new lightweight materials and structures pose to spot joining process will be presented, the bottleneck of the existing processes will be analyzed, and finally some newly developed processes will be introduced, such as magnetic assisted dissimilar Al/Steel resistance spot welding which was proposed to solve the problems caused by inherent oxide film at aluminum/steel interface, friction self-piercing riveting (F-SPR) which was proposed to solve the cracking problem occurring in traditional SPR process of low ductility light metals (e.g., 7xxx, Mg and cast Al) and improve the sealing problem occurring in flow drill screw (FDS) of battery packs, and friction stir riveting (FSR) which was proposed to realize spot joining of light metal to UHSS. |