Consideration of direct and reverse redrawing of copper sheet by rigid-plastic finite element

By using Rigid-Plastic FEM, direct and reverse redrawing processes have been simulated. The simulation results show that success or failure of the direct redrawing process depends not only on the conventional process and material parameters but also depends on the angle θ. This angle which is defined as the angle between the tangent line to the die and the cupholder with the axes of drawing, is the main parameter in controlling the different drawing ratios achieved by reverse and direct redrawing. In all ranges of second drawing ratios, there is a critical angle, below which direct redrawing lead to higher drawing ratios. For example, in the case of a first redrawing ratio equal to 1.5, reverse redrawing lead to a second drawing ratio equal to 1.45 whilst by changing the angle θ from 30 degrees to 50 degrees, second drawing ratios ranging from 1.5 to 1.35 is obtainable in direct redrawing.