With different die temperatures, a series of drawbead restrain force(DBRF) tests were carried out by applying normally used half-round drawbead. The results show that the DBRF changes greatly with the increase of die temperature, which has unnegligible influence on the accuracy of the mathematical solution model for DBRF. Considering the influence of die temperature and the ratio of R/t(drawbead radius / sheet thickness), a new improved mathematical solution model for DBRF was proposed. Compared with several normally used mathematical solution models, the new model has a maximum error of 7% in calculating DBRF, which has a higher solution precision.
|