Influence of Punch Profile Radius on Deep Drawability of Stainless Steel and Aluminum Clad Sheet

This study deals with a stainless steel and aluminum clad sheet produced by pressure-welded hot rolling. Tensile tests on the clad sheet and the elements which compose it show that the aluminum portion has higher uniform ductility than the stainless steel portion and that the latter has higher local deformation compared with the former. In the process of deep drawing, the influence of blank setting and punch profile radius was studied. Deep drawability improves when aluminum is set on the outer side of the cup because compressive stress which occurs on the punch profile due to bending suppresses crack initiation in stainless steel. At punch radius of 4 mm, deep drawability improves because tensile load is applied on a larger area. Fracture and deformation mechanisms were clarified by examining in detail results of thickness strain measurements.