飞机铝合金双曲度蒙皮充液成形的数值模拟与试验

Numerical simulation and experiment on the hydroforming for double curved aircraft aluminum alloy skin

针对某型飞机上蒙皮零件,基于有限元分析软件Dynaform,对主动式充液成形和被动式充液成形两种方案进行了数值模拟对比分析。根据数值模拟结果,认为该零件较适合采用主动式充液成形,其次,通过修改工艺补充面和优化成形工艺参数,有效地控制零件的最大减薄量。同时,保证一定的减薄量,使板料达到塑性变形状态,从而有效减小回弹。再通过回弹分析,根据回弹量计算结果,运用Think Design软件对模具型面进行回弹补偿,将回弹量控制在合格范围内。最终通过实际试模,验证了数值模拟的准确性及适用性,加工出表面质量良好、精度满足要求的合格产品。

For a aircraft skin part, two kinds of schemes as active hydroforming and passive hydroforming were numerically simulated and comparatively analyzed by the finite element analysis software Dynaform. According to the numerical simulation results, the above part was suitable for the active hydroforming. Then, the maximum reduction of parts was effectively controlled by modifying the addendum surface and optimizing the parameters in forming process. At the same time, a certain amount of thinning of the sheet was ensured to make the sheet metal into plastic deformation, thereby the springback is effectively reduced. Then, according to the analysis and the calculation resuits of springback, the springback of die surface was compensated by the software Think Design , and the springback quantity was controlled within the qualified range. Finally, the accuracy and applicability of the numerical simulation were verified by the experiment, and qualified parts with good surface quality and high accuracy were formed.