铝合金变速箱外壳压铸模设计及工艺分析

Die Casting Die Design and Process Analysis of Aluminum Alloy Gearbox Housing

针对铝合金铸件在压铸充填过程中常伴有气孔、缩孔、冷隔等缺陷的现象,以汽车铝合金变速箱外壳为例,分析变速箱外壳的结构特征,对其浇注系统、冷却系统、抽芯结构进行设计,确定最佳工艺参数,经过试验与分析,最终经过实际压铸生产验证,确定了工艺方案的合理性。结果表明:当定模温度为200℃、动模为220℃、铝液浇注温度为670℃、慢压射速度为0.18 m/s、快压射速度为4.5 m/s、内浇道的压射速度为48 m/s、留模时间为30 s时,铸件成形品质较好。合理压铸工艺设计不仅能提高生产效率以及产品的合格率,还能简化模具设计制造流程,减少模具开发成本。

Aluminum alloy castings are often accompanied by blowhole,shrinkage holes,cold shut and other defects during the die-casting filling process.In the work,taking the aluminium alloy gearbox for automobile as an example,the structural characteristics of the gearbox housing was analyzed,and the pouring system,cooling system,and core puller were designed.After the optimal process parameters were determined,the actual diecasting production was conducted.The good casting quality was obtained when optimal process parameters were as follows:the fixed die temperature 200℃,the moving die temperature 220℃,the molten aluminum casting temperature 670℃,the slow injection speed 0.18 m/s,the fast injection speed 4.5 m/s,the injection speed of the inner gate 48 m/s and the die opening time 30 s.Reasonable die-casting process can not only improve production efficiency and overall yield of castings,but also simplify die processing procedures,thereby reducing die development cost.