铝合金曲面斜法兰罩盖成形工艺的数值模拟与试验研究

Numerical simulation and experimental investigation on forming process for aluminum alloy cover with curved oblique flange

研究了铝合金罩盖刚性模拉深预成形-新淬火-充液拉深终成形的多道次成形工艺。通过分析零件的几何特征,确定预成形中间构型的几何形状以及确定合理的冲压方向。基于有限元分析软件Dynaform对成形工艺进行模拟分析,优化成形过程的关键工艺参数,并进行试验验证与优化。研究表明:液室压力及加载路径对充液拉深成形零件质量影响较大,成形所需最大液室压力为15 MPa,充液拉深终成形后的零件壁厚最大减薄率为11.424%,侧壁与法兰没有明显的起皱趋势。试验证明对于该铝合金罩盖零件,采用刚性模拉深预成形-新淬火-充液拉深终成形的多道次成形工艺较传统多道次拉深工艺有明显的优势,可得到表面质量良好的合格零件。

The multi-step forming process combining preforming of rigid mould deep drawing,new quenching and final forming of hydrodynamic deep drawing for the aluminum alloy cover was studied.Firstly,geometric features of parts were analyzed,and the geometry shape of preformed intermediate configuration and the reasonable stamping direction were determined.The forming process was simulated and analyzed,and the key process parameters were optimized based on the finite element analysis software Dynaform.Meanwhile,the results of numerical simulation were optimized and verified by experiment.The results show that the cavity pressure and loading paths have great influence on the quality of part.The maximum cavity pressure required for the forming process is 15 MPa and the maximum thinning rate of part wall thickness is 11.424% after the final forming of hydrodynamic deep drawing.There is no obvious wrinkling tendency in the side wall and flange.For the aluminum alloy cover,the multi-step forming process combining preforming of rigid mould deep drawing,new quenching and final forming of hydrodynamic deep drawing has obvious advantages compared with the traditional multi-step drawing process,and the qualified parts with good surface quality can be obtained.