微型车后桥液力成形工艺的理论与仿真研究

Theory and simulation study on hydraulic bulging process of mini-car rear axle

为了对桥壳管件在不同加载路径下的成形情况及变形规律进行预测,达到降低管件胀形工艺的开发成本及试验费用的目的,采用理论研究与仿真分析相结合的方法对胀形桥壳的失效形式、壁厚分布以及加载路径进行研究。基于ABAQUS有限元软件对铝合金管件的胀形过程进行数值模拟,通过将实验结果与仿真分析结果的对比,验证有限元模型的正确性;以此为基础,针对微型车后桥胀形工艺进行数值模拟,通过分析、总结,获取了合理的加载路径。研究结果表明,后桥预胀形和终胀形合理的加载路径分别为常压47 MPa和多线性加载路径4,终胀形时进行退火处理,减小了管件在预胀形过程中产生的残余应力,胀形结果也更加理想。

Theoretical research and simulation analysis were combined together to study the failure modes, and thickness distribution of the wall and load paths during the hydraulic bulging process of rear axle in order to predict the forming situation and regular patterns of rear axle tube under various load paths, which reduces the developmental and experimental cost for the bulging process. The bulging process of aluminum alloy tube was simulated using ABAQUS finite element software. Simulated results were verified by the experimental results. Based on the above results, the bulging process of mini-car rear axle was numerically simulated and the reasonable load paths were obtained through analysis and summary. The results show that reasonable load paths in pre - forming and final bulging stage are constant pressure 47 MPa and multi-linear loading path 4, respectively. The rear axle after the final bulging stage is treated with annealing to reduce the residue stress from pre-forming so that a better bulging result is obtained.