This paper studies the effects of some modeling parameters on the accuracy of finite element simulation in sheet-metal forming. A simple stepdie, which simulates binder forming, is used. In this two-dimensional case, a flat blank is bent into an S-shape, which has an exact solution. Four modeling parameters are studied. They are: die close speed, die gap, mass damping, and width of blank. One significant finding of this study reveals that in calculations using explicit finite elements, the simulation speed should be selected with care. The dynamic effects may be prevalent if the simulation speed is too fast. Numerical errors may accumulate and renders the results erroneous if it is too slow.

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