轮毂闭式反挤压成形工艺研究

汽车轻量化是世界汽车发展大趋势。试验证明,汽车整备质量每减少100kg,百公里油耗可降低0.3~0.8L。目前大部分汽车安装的轮毂为铸造铝合金轮毂(以乘用车为主)或钢质车轮(以商用车为主)。锻造铝合金轮毂重量比铸造铝合金轮毂的重量轻10%左右,比钢质轮毂重量轻2/3左右。因此,采用锻造铝合金轮毂符合汽车轻量化发展的大趋势。市场上锻造轮毂成形工艺复杂,导致锻造轮毂成本过高,锻造轮毂的应用推广较为缓慢。闭式反挤压成形工艺利用一套模具直接成形轮毂的轮辋、轮缘,缩短轮毂锻件成形工序。因此,闭式反挤压成形轮毂工艺可降低锻造轮毂生产成本,加速推广锻造轮毂的应用和汽车轻量化的进程。闭式反挤压成形轮毂工艺通过有限元模拟及试验验证,证明该工艺稳定、可行。

Study on closed backward extrusion process of wheel hub

Automobile lightweight is the world automobile development trend.The test shows that for every100 kg reduction in vehicle curb weight,the fuel consumption per 100 km can be reduced by 0.3-0.8 L.At present,most automobile wheels are cast aluminum alloy wheels(mainly for passenger cars)or steel wheels(mainly for commercial vehicles).The weight of forged aluminum alloy wheel hub is about 10%lighter than that of cast aluminum alloy wheel,and about 2/3 lighter than steel wheel hub.Therefore,forging aluminum alloy wheel hub is in line with the development trend of automobile lightweight.The complex forming process of forging wheel hub in the market leads to the high cost of forging wheel hub,and the application and promotion of forged wheel hub is relatively slow.The closed back extrusion process uses a set of dies to directly form the wheel rim and rim of the wheel hub to shorten the forming process of the hub forging.Therefore,the closed back extrusion process can reduce the production cost of forging wheel hub,accelerate the application of forged wheel hub and the process of automobile lightweight.Finite element simulation and experimental verification show that the process is stable and feasible.