复杂深筒铝合金轮毂锻件精密成形工艺及模具技术

Precision forming process and die technology on complex deep cylindrical aluminum alloy wheel hub forgings

针对复杂深筒形铝合金飞机轮毂存在的表面质量要求高、非机械加工面多、形状复杂等特点而导致的精密成形难度大的问题,提出了毛压+预压+终压的成形工艺。利用数值模拟软件DEFORM及工艺试验,对复杂深筒轮毂精密成形工艺和模具结构进行设计和优化,并基于工艺试验结果对实际生产条件下的成形缺陷进行分析。结果表明:3工序成形工艺能较好地成形锻件;工艺试验中实际边界条件与仿真时理想边界条件间较大的差异是试验中充不满及折叠等成形缺陷产生的主要原因;基于数值模拟及优化分析,分别提出了改变坯料定位方法、镦粗成形毛压法兰及终压模具增设桶形内飞边等特殊结构及方法对轮毂成形进行优化,最终实现了复杂深筒形类铝合金飞机轮毂精密模锻的成功试制。

For the problems of difficulty in precision forming for complex deep cylindrical aluminum alloy aircraft wheel hub caused by the characteristics of high surface quality requirements, many non-machined surfaces and complex shapes, a forming process of initial-extrusion+pre-extrusion+final-extrusion was proposed. Then, the precision forming process of complex deep cylindrical wheel hub and mold structure were designed and optimized by numerical simulation software DEFORM and process tests, and the forming defects under actual production conditions were analyzed based on the process test results. The results show that the three-step forming process can form the forgings well, and the large difference between the actual boundary conditions in the process experiment and the ideal boundary conditions in the simulation is the main reason for the forming defects such as dissatisfaction and folding in the process experiments. Based on the numerical simulation and optimization analysis, the special structures and methods such as changing the positioning method of blank, upsetting and forming the rough flange and adding a barrel-shaped inner flash in the final-extrusion die are proposed to optimize the hub forming. Finally, the trial production of precision die forging for complex deep cylindrical aluminum alloy aircraft hub is successful.