凸模加载速度对某航空导管双翻边成形不均匀变形的影响

Effect of loading speed of punch on uneven deformation of double flanging forming for an aviation tube

为解决5A02薄壁铝合金导管的不均匀变形影响其成形质量的问题,基于有限元仿真,并结合理论和实验方法,对5A02铝合金管件端头多道次双翻边的不均匀变形进行了深入研究。解决了该成形过程中有限元建模关键技术,建立了导管多道次双翻边成形有限元仿真模型,基于该模型获得了真应力-真应变规律;并提出了不均匀变形度表征方法,研究获得了凸模的加载速度对铝合金管件端头双翻边成形不均匀变形度的影响规律。结果表明,随着凸模加载速度的变大,管件端头第1道次变形的不均匀度先增加后减小,第2道次变形的不均匀度基本保持不变,第3道次变形的管件不均匀度先减小然后增大。较大的变形主要分布在成形区的圆角弯曲部分区域和靠近管件内层外表面的部分区域。

To solve the problem of forming quality effected by uneven deformation of 5A02 thin-walled aluminum alloy tube,based on finite element simulation and combined with theoretical and experimental methods,the uneven deformation of 5A02 aluminum alloy tube end with multi-pass double flanging was studied deeply.The key technologies of finite element modeling for the forming process were solved,and a finite element model of the multi-pass double flanging forming of aviation tube was established,and the true stress-true strain law was obtained based on the model.Meanwhile,the representation method of the uneven deforming degree was proposed,and the influence of loading speed of punch on uneven deformation degree during the double flanging forming process of aluminum alloy tube end was studied.The results show that with the increase of loading speed of punch,the uneven deformation degree of tube end increases firstly,and then decreases in the first pass of forming,the uneven deformation degree of tube end is basically unchanged in the second pass of forming.And in the third pass,the uneven deformation degree of tube decreases firstly and then increases.The larger deformation is mainly distributed in the rounded corner bending part of the forming zone and the part near the outer surface of inner layer of the tube.