通过数值模拟计算,发现低压铸造铝合金轮毂在充型完成后的很短时间内,铸件各部分都开始凝固,差别在于每一时刻各部位固相率不同。铸件缩松产生的原因是补缩通道的凝固冷却曲线与被补缩部分的凝固冷却曲线存在部分重合。在不改变模具结构的情况下,在上下模具轮辐对应部位覆盖隔热层,可使得轮辐部位的凝固冷却曲线位置升高,实现轮辐处冷却曲线与轮辋与轮辐的连接处的冷却曲线分离,消除轮辋与轮辐连接处的缩松缺陷;覆盖隔热层后,被覆盖的模具部分温度升高了20℃左右。 Through numerical simulation, found that low-pressure cast aluminum alloy wheel in the filling after the completion of a very short period of time, all parts of the casting began to solidify, the difference is that each time the solid fraction of different parts. The reason for casting shrinkage is that the cooling curve of the solidification cooling curve of the shrinkage channel partially coincides with the solidification cooling curve of the part being shrunk. Without changing the structure of the mold, the upper and lower mold spokes covering the corresponding parts of the insulation layer can make the location of the spoke cooling coagulation curve increased, to achieve the cooling curve at the spoke and the rim and the spokes at the junction of the cooling curve separation, elimination Rim and spoke connections at the Department of shrinkage defects; covered insulation, the part of the mold covered by the temperature increased by about 20 ℃.