AC7A铝镁合金端盖的铸造工艺

Production of AC7A Alloy End Cover by Low Die Casting

优化了AC7A合金的成分组成,满足了300km/h动车组牵引电机对材料力学性能的特殊要求。熔炼过程分两阶段进行的方法,有效地控制了Fe、Si两种元素对合金液的污染。合金液在覆盖熔剂保护下进行熔炼和浇注的方法,预防了铸件针孔缺陷的产生。低压铸造工艺引入阶梯式双层浇注系统后,解决了Al-Mg合金易产生夹渣和缩松的问题。

Through optimizing the composition proportion based on experiment and analysis,AC7A alloy can meet the special mechanical property requirements of drawing engine for 300 km/h electric motive unit. The pollution of Fe and Si elements in alloy melt can be effectively controlled by conducting two-stage smelting. Pin-hole defect in the end cover can be greatly eliminated by smelting liquid alloy under coving flux and pouring. Inclusion and shrinkage porosity in the Al-Mg alloy end cover can be eliminated by adopting multi-step two-layer pouring system in low pressure casting.