精密铸造大型蜡模成形过程的数值模拟

Numerical Simulation of the Forming Process for a Large-Sized Wax Pattern of Investment Casting

基于Moldflow软件对某大型复杂蜡模的成形过程进行了数值模拟,并在同等工艺条件下通过注蜡试验评价计算准确性。选用的KC4017B造型蜡具有非牛顿流体特征。计算结果表明,流体前沿在行进至内环环面时出现了明显停滞,流动前沿温度突然降低,形成12处充填不足的区域。试验蜡模在相同位置也出现了充填不足的孔洞,验证了数值模拟的准确性。

The numerical simulation of the forming process for a large-sized complex wax pattern was carried out based on Moldflow software, in addition, the calculation accuracy was evaluated through the wax injection experiment under same process conditions. The selected KC4017B modelling wax was of typical nonNewtonian fluid characteristics. The calculation results show that the fluid fronts stop obviously when they advance into the inner ring surface, and the fluid front temperature here dropped sharply, leading to produce 12 misrun areas. The experimental wax patterns showed the similar defects, which verified the accuracy of the numerical simulation.