板材无压边多点成形中起皱的数值模拟

在多点成形中，变形量不大的三维曲面零件通常采用无压边的方式成形。起皱是无压边成形中决定零件能否成形的重要因素。采用显式算法对不同板厚、不同变形程度以及不同材质的球面、马鞍面的无压边多点成形过程进行数值模拟，得出了起皱的分布和不起皱极限图，这些结果对多点成形技术的工程应用具有一定的参考价值。

Numerical Simulation of Wrinkling in Multi-point Forming for Sheet Metal without Blank Holder

In multi-point forming (MPF), three-dimension surface parts with small deformation are usually formed in a mode without blank holder. In such mode, wrinkling is a key factor to determine whether the part could be formed. Based on explicit algorithm, the MPF processes of spherical and saddle surface parts of different materials with different thickness and deformations were simulated in this paper, and wrinkle distribution and non-wrinkling limits for spherical and saddle surface parts were obtained. These results provided significant guidance to the engineering application of MPF technique.