Experimental and finite element investigation on wrinkling of circular single layer and two-layer sheet metals in deep drawing process

Abstract

This paper deals with the comparison of wrinkling behavior of both single and two-layer sheets in the deep drawing process. Unfortunately, due to the significant difference in the material properties of the two layers, it is very challenging for the finite element method to predict the location and relative possibility of wrinkling in the multilayer sheets. Blank holder force (BHF) has a significant effect on the failure mode of sheet metals. By decreasing BHF, wrinkling turns out as the principal failure mode, whereas its increase results in splitting and fracture. Thus, this paper investigates the effect of blank holder forces on wrinkling and fractures in drawing process of single and two layers. Moreover, the effect of material and arrangement of layers on wrinkling, fracture, and required deformation forces in the cylindrical deep drawing will be discussed. Results show that the optimum blank holder force for two-layer sheets is affected by the material and arrangements of lay-ups.