拉形与充液复合成形工艺的数值模拟研究

Research on compound forming process of stretch forming and hydroforming based on numerical simulation

根据单拉实验获得铝合金2024-O的材料力学性能,通过Dynaform有限元分析软件对拉形与充液复合成形工艺进行了数值模拟研究,并分析了复合成形下零件的减薄率、FLD成形极限和回弹,得到了成形零件的减薄率、成形极限图和贴模度回弹数值。结果显示,相比原有的蒙皮拉形工艺,该复合成形工艺可以将高难度零件成品率从10%提高至80%,消除了部分区域的过分减薄,局部最大减薄率从22%降低至15%以内,极大地提高了零件的工艺稳定性。同时,该复合成形工艺综合了蒙皮拉形和液压成形的优势,使零件变形量均匀分布,有效提高了零件的定形性。最终通过实验验证了复合成形工艺的可行性和可靠性。

The mechanical properties of aluminum alloy 2024-O were obtained by uniaxial tensile test,and the compound forming process of stretch forming and hydroforming was numerically simulated by finite element analysis software Dynaform. Then,the thinning ratio,FLD forming limit and springback of parts in the compound forming process were analyzed,and the thinning ratio,forming limit diagram and springback value of forming parts were obtained. The results show that comparing with the original skin stretch forming process,the compound forming process improves the yield of difficult parts from 10% to 80% and eliminates the excessive thinning of partial areas with the local maximum thinning ratio decreasing from 22% to 15%,and the process stability of parts is greatly improved. Meanwhile,the compound forming process combines the advantages of skin stretch forming and hydroforming,and the deformation of parts is evenly distributed as well as the fixability of parts is effectively improved. Finally,the feasibility and reliability of the compound forming process were verified by experiment.