2010 Volume 51 Issue 592 Pages 450-454
A new forming method has been developed to improve the press formability of steel sheets. Detaching die surfaces from a steel sheet blank during the forming process is a distinctive feature of the developed method, and such a motion is repeated for several times until the end of the forming process. Results of sliding tests clarified that just detaching die surfaces from a steel sheet blank during the sliding process could improve the frictional conditions between steel sheets and die surfaces. As a result, the developed method could reduce the forming load and improve the forming limit of steel sheets. Finally, it was shown that the developed method, which was automated using servo press and die cushion systems could effectively improve the deep drawability of 590MPa-grade high-strength steel sheets, even if the pressed panel was a full-scale panel for auto parts.
