High-speed friction stir welding in light weight battery trays for the EV industry

Abstract

Present work aims to achieve high welding speed during friction stir welding of lightweight battery trays in the electric vehicle industry. This study reports high-speed friction stir welding (HSFSW) up to 4.0 m min−1 in AA6063-T6 alloys. The defect-free HSFSW joints are produced by adopting aggressive material mixing, i.e. higher tool rotation and plunge force. HSFSW weld cross-section reported an unusual hardness profile of ‘U’ shape instead of ‘W’ shape in conventional FSW of AA6xxx alloys. HSFSW resulted softening of weld stir zone (∼60HV) along with HAZ (∼53HV) against the base material (BM) hardness of ∼90HV. The HSFSW at 4.0 m min−1 obtained good joint strength of 71% of the BM. Microstructure evolutions across the fractured weld cross-section are discussed using EBSD analysis.