蒙皮件多点拉形过程中成形缺陷的数值模拟

多点拉形是一种将柔性制造技术和计算机技术结合为一体的先进制造技术。文章基于动力显式有限元算法,从板厚、材质、变形程度和塑性指数等工艺参数入手,对球形和鞍形件的多点拉形过程进行数值模拟。研究表明,正确的选择工艺参数可以减轻或消除压痕缺陷。同时利用显-隐式算法,分析了板材厚度和成形件目标曲率半径对回弹的影响,得到了回弹的趋势和分布规律,即回弹量与板材厚度成反比,与成形件的曲率半径成正比。研究结果对蒙皮件多点拉形技术的实际应用具有一定的参考价值。

Numerical simulation study about forming defects on the process of multi-point stretch-forming for skin parts

Multi-point stretch-forming is an advanced manufacturing technology for sheet metal forming, which combines flexible manufacturing technology with computer technology. In this paper, based on the dynamic explicit finite algorithm, the multipoint stretch-forming processes of sphere and saddle parts, with different thicknesses, different materials, different deformations and other technical parameters are simulated. The results indicate that proper choice of technical parameters can alleviate or eliminate dimpling defects. Simultaneously, based on explicit-implicit algorithm, the springback processes are simulated with different thicknesses of blank under different curvature radius. The trend and distributing rule of springback are obtained. The quantity of springback is an direct ratio to the thickness of blank, and is an inverse ratio the radius of curvature. These results provide significant guidance to the practical application of multi-point stretch-forming technique for skin parts.