Studies on optimization of metal forming processes using sensitivity analysis methods

In this paper, an optimization method for metal forming processes, especially for forging process designs using finite element based sensitivity analysis method is briefly introduced. On the basis of the authors' previous studies, this paper gives further improvements concerning several critical techniques of the optimization method. An approach for improving the computational efficiency is introduced and demonstrated. After introducing the optimization method of multi-stage forming processes, the paper presents an optimization method for single stage forming processes. The initial billet dimension is optimized for achieving a net-shape final forging. Besides, the paper also gives a method for dealing with the velocity sensitivity boundary conditions for both moving upper dies and stationary lower dies. Using this boundary condition treatment method, not only can we optimize the upper die shape but also the lower die shape, even if both of the dies have different shapes. The paper also extends the optimization to the more complex forming processes with multiple cavities. (C) 2004 Elsevier B.V. All rights reserved.