汽车排气管件内高压成形数值模拟及试验

Numerical simulation and experiment of the hydroforming for automobile exhaust pipe

利用有限元分析软件,对汽车排气管件的压弯和内高压成形过程进行了数值模拟,研究了压弯成形过程中管坯在不同弯曲变形量下的壁厚分布和内高压成形过程中压力加载路径对成形零件壁厚的影响。基于有限元模拟结果,进行了压弯成形和内高压成形实验。结果表明,压弯成形和内高压成形弯曲叠加处最易破裂;通过优化加载路径可避免缺陷,获得壁厚均匀性较好的成形零件;成形实验结果与数值模拟结果一致。

Numerical simulation of bending and hydroforraing of automobile exhaust pipe was conducted by using finite element analysis software. The wall thickness variation under the different deformation conditions for bending process was analyzed. Further, the effects of the loading paths on the forming of hydroformed part were analyzed in details. Subsequently, the bending and hydroforming experiments were carried out based on the simulation results. The forming results indicated that the superposition region of bending and hydroforming is most easy to rupture. The forming defects could be avoided and the hydroforming part with high thickness uniformity was obtained through the optimization of the loading paths. The experimental results are approximately accordant with the simulative ones.