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Deep drawing experiments using rectangular pans, made of aluminum alloys, have been conducted at the Engineering Research Center for Net Shape Manufacturing (ERC/NSM) at the Ohio State University. A 160 ton Minster hydraulic press was used for the experiments. A 3-D finite element code called PAM-STAMP was used in the simulations. The current study investigates the effect of blank holder force control and blank shape on the final product quality. In the hydraulic press, it was possible to control the blank holding force (BHF) as a function of time. By conducting experiments and simulations using three blank shapes and various BHF profiles, it has been shown that blank shape and the BHF have significant effect on the formability of aluminum alloy pans, and they must be optimized to eliminate wrinkling and fracture. A decreasing BHF profile was shown to be effective in improving part quality and practical for use in industrial applications.

Recent studies in sheet metal forming, conducted at universities world wide, emphasize the development of computer aided techniques for process simulation. To be practical and acceptable in a production environment, these codes must be easy to use and allow relatively quick solutions. Often, it is not necessary to make exact predictions but rather to establish the influence of process variables upon part quality, tool stresses, material flow, and material thickness variation. In cooperation with its industrial partners, the ERC for Net Shape Manufacturing of the Ohio State University has applied a number of computer codes for analysis and design of sheet metal forming operations. This paper gives a few selected examples taken from automotive applications and illustrates practical uses of computer simulations to improve productivity and reduce tool development and manufacturing costs.

Process simulation for product and process design is currently being practiced in industry. However, a number of input variables have a significant effect on the accuracy and reliability of computer predictions. A study was conducted to evaluate the capability of finite element method (FEM) simulations for predicting part characteristics and process conditions in forming complex-shaped, industrial parts. In industrial applications, there are two objectives for conducting FEM simulations of the stamping process: (1) to optimize the product design by analyzing formability at the product design stage and (2) to reduce the tryout time and cost in process design by predicting the deformation process in advance during the die design stage. For each of these objectives, two kinds of FEM simulations are applied.