CRITICAL CONDITIONS OF WRINKLING IN DEEP-DRAWING AT ELEVATED-TEMPERATURE

A theoretical model has been developed to predict the critical conditi ons of wrinkling and the number of wrinkles, both at room temperature and elevated temperature, in the deep-drawing process. The equilibrium of moments acting on a segment of wrinkled flange is applied to exami ne the critical conditions of wrinkling. The critical conditions where wrinkling is formed are determined for the cases with a blank holder and without a blank holder. The results of the theoretical solution ar e compared with the experimental results at ambient and elevated tempe ratures, good agreement being found. (C) 1998 Elsevier Science S.A. Al l rights reserved.