摘要
Major defects in forming of conical cups are wrinkles and rupture.Hydrodynamic deep drawing assisted by radial pressure（HDDRP） is a sheet hydroforming process for production of shell cups in one step.In this work,process window diagrams（PWDs） for Al1050-O,pure copper and DIN 1623 St14 steel are obtained for HDDRP process.The PWD is determined to provide a quick assessment of part producibility for sheet hydroforming process.Finite element method is used for this purpose considering the process parameters including pressure path,and the blank material and its thickness.Numerical results are validated by experiments.It is shown that the sheets with less initial thickness and higher strength show better formability and uniformity of thickness distribution on final product.The results demonstrate that the obtained PWD can predict appropriate forming area and probability of rupture or wrinkling occurrence under different pressure loading paths.
起皱和破裂是锥形杯成形过程中的主要缺陷。径向压力辅助充液拉深是一步成形筒形件的板材液压成形技术。获得了径向压力辅助充液拉深Al1050-O、纯铜和DIN1623 St14钢板的工艺窗口图。该工艺窗口图可快速评估板材液压成形零件的可制造性。采用有限元方法对径向压力辅助充液拉深进行模拟,并研究压力路径和原始材料及其厚度的影响。通过实验对模拟结果进行验证。结果表明:对于初始厚度较薄和强度较高的板材,其成形性更好,最终产品的的厚度分布也更均匀。所得工艺窗口图可以预测在不同加载路径下合适的加工区间以及破裂或起皱的可能性。
