Digital tryout based on the optimal blank design toward realization of beadless stamping
Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture
Published online on July 30, 2013
Abstract
As the shapes of stamped parts become more complicated and the trend toward light weight continues, making a stamping die becomes more difficult because of inevitably poor formability. Poor formability can be improved if the material flow during stamping is carefully controlled. The application of a drawbead has become common to retard metal flow into the die cavity at the region where a wrinkle is expected. However, the effects of drawbeads are contradictory; for example, one effect prevents wrinkling and another aggravates fracture. Since the blank’s shape also controls the material flow, the beadless stamping process has been devised. In this process, the role of the drawbead is replaced by the shape of the blank. The author developed a digital tryout that emulates a real tryout process wherein a deformation process analysis has been iteratively carried out with a trial blank and the analysis result is carefully investigated. Since the control variable of the proposed digital tryout is the deformed shape, the trial blank shape that corresponds to the desired deformed shape is determined with an optimal blank design method. The present digital tryout was iteratively performed by changing the desired deformed shape until the analysis results predicted no wrinkling and no fracture. The validity of the proposed method was confirmed through an application using a real automotive part.