Abstract: A proposition of computer-aided design for cylindrical dies to pres metal plates is suggested. A thorugh discussion on the implementation of this idea is made. A series of new algorithm is adopted: (1) the Lagrange interpolation to treat the true stress-strain relationship of arbitrarily given materials; (2) the piecewise curve fit by spline to obtain curvature function; (3) the least square collocation-POWELL method to solve the nonlinear differential equations. Thus, the final shape of a die can be easily obtained by the application of the present method, as long as the geometry of a workpiece is specified. As an example, a U-shaped die to press the 2024-T4 aluminium plates is then designed by this approach. Results with very good accuracy are obtained. The idea can be used to more complicated problems.

Key words: 弹塑性弯曲成形, 辅助设计, 柱面曲模