支叉管零件充液成形工艺

Hydroforming process of fork tube parts

针对某军机支叉管类零件的结构型面复杂、曲率变化大的特点,其传统的成形方式主要采用落压成形,在成形过程中易产生起皱、破裂和表面质量差等问题。因此,提出采用被动式充液成形来加工支叉管零件,并利用有限元软件ANSYS/LS-DYNA建立有限元分析模型,对其充液成形过程进行有限元仿真模拟,研究不同压边力对充液成形的影响,从模拟结果可以得出合理吨位的压边力为300 kN。最后,通过实验研究对模拟结果进行验证,试制出合格的零件,得到支叉管零件采用被动式充液成形的最优工艺参数为压边力为300 kN、液室压力为8 MPa、压边间隙为1.05 mm,零件成形后的最大减薄率可以控制在20%以内,为支叉管零件成形找到了合适的工艺方法,利用数值仿真分析对成形复杂深腔、盒型类零件提供理论和数据支撑。

The fork tube parts of a certain military aircraft have the characteristics of complex structure surface and large curvature change, and the traditional forming method mainly adopts the method of falling pressure forming, which has problems such as wrinkles, cracks and poor surface quality during the forming process. Therefore, the passive hydroforming was put forward to form the fork tube parts, and the finite element analysis model was established by finite element software ANSYS/LS-DYNA to simulate the passive hydroforming process. The influences of different blank holder forces on the hydroforming was studied. From the simulation results, a reasonable blank holder force was 300 kN, and the simulation results were finally verified by experimental research. Furthermore, the qualified parts were trial-produced, and the optimal process parameters of passive hydroforming for fork tube parts were obtained with the blank holder force of 300 kN, the pressure chamber of 8 MPa and the blank-holder clearance of 1.05 mm. In addition, the maximum thinning rate was controlled within 20% after part forming, the suitable process method for fork tube parts forming was found, which provided theoretical and data support for forming parts with complex deep cavity or box shape by numerical simulation analysis.