铝青铜铸件低压铸造工艺参数的计算机模拟及优化

Simulation and Optimization of Low Pressure Casting of Aluminum Bronze Part

为确定铝青铜铸件低压铸造的最佳工艺参数,利用Procast软件模拟了砂型低压铸造铝青铜泵盖铸件的凝固过程及缩孔分布。通过对不同砂型、浇注速度、浇注温度条件下铸型充填、凝固过程的模拟以及对缩松缺陷预测的分析比较,优化出低压铸造的合理工艺参数为:顺序凝固浇注速度、温度在不出现冷隔的前提下,越低越好,1150℃为最佳浇注温度;铸型的导热系数越小越不易出现集中缩孔缩松,硅砂型为最佳铸型;由快变慢的压力变化充型方式比匀速充型更能减少铸件的缩孔缩松,更有利于顺序凝固,按照P=6000t曲线加压铸件最佳。

To determine the best process parameters for low-pressure casting of aluminum bronze parts,the solidification process and shrinkage cavity distribution of the sand mold low-pressure casting aluminum bronze pump cover parts were simulated by Procast software.Through the simulation of mold filling and solidification processes under different sand molds,different pouring speeds and temperatures,as well as the analysis and comparison of shrinkage defects prediction,the reasonable process parameters for low-pressure casting were optimized as follows:under the premise of no cold barrier,the lower the sequential solidification pouring speed and temperature,the better the result would be,and 1150℃was the best pouring temperature.The smaller the thermal conductivity of the mold,the less likely it was to have concentrated shrinkage,and silica sand mold was the best mold.The pressure change filling method from fast to slow pressure can reduce the shrinkage and porosity of the casting more than the uniform speed filling,and it was more conducive to sequential solidification,and it was the best for the parts according to curve P=6000t.