Shape precision improvement of impact extruded 3003 aluminum alloy square cups by means of ironing

Abstract

Electric vehicles and emergency batteries will be increasingly required and widely used in the future. With this background, there is demand for new technologies that can efficiently produce containers with a rectangular cross section (square cups) used for the battery cases which are essential for electric vehicles and emergency batteries. In this study, we clarified that the large square cups can be formed by impact extrusion, which is more efficient than deep drawing. In addition, we also clarified that the square cups with increased shape accuracies and uniform thickness in their side walls can be obtained by performing ironing after impact extrusion, enabling the successful forming of high-accuracy square cups that can be used for battery cases. Moreover, concerning the thin-wall edge for positioning a plate lid that is subsequently attached to square cups along one of their edges, we proposed a new method of forming the thin-wall edge at the sometime during the ironing step.