Optimization of an Anisotropic Blank Shape Based on Ideal Sheet Forming Design Theory and FEM Analysis

Abstract

Most of the currently available experimental and analytical technologies for optimizing sheet metal forming processes are intrinsically indirect tools for design purposes. Therefore, it usually takes a significant number of iterations to obtain optimum processes. In order to better guide this iterative procedure by overcoming the indirect nature of the current tools, a direct design theory called ideal forming theory was previously developed [1–3]. The essence of this process design theory is that material elements are prescribed to deform along minimum plastic work paths (or proportional logarithmic strain paths), assuming that such paths provide optimum formability. Then, the optimum forming processes are obtained so as to have the most desirable strain distributions in final products. As output, the design theory provides the ideal forming process parameters such as the optimum initial blank shape and optimum strain distribution as well as intermediate shapes of products and boundary traction histories.