保持架挤压铸造充型和凝固过程的数值模拟

Numerical simulation of filling and solidification processes in squeeze casting of bearing cage

为实现对挤压铸造生产过程的精确控制,运用有限元模拟软件对镁合金轴承保持架进行挤压铸造充型和凝固过程的数值模拟,得出最佳的挤压铸造工艺参数.优化的工艺参数为:浇注温度710℃,模具预热温度180℃,冲头压射速度25mm/s,比压200MPa,保压时间约为20s.建立了充型时间和凝固时间与模具预热温度和冲头压射速度的数学关系式,并对液态合金的充型及凝固过程进行了可视化观察.模拟结果表明,充型、凝固过程合理,铸件结构完整,效果良好,说明镁合金轴承保持架具有良好的成形性.将此模拟结果应用到实践中,可优化挤压铸造过程,提高工作效率.

In order to realize the precise control for squeeze casting process of the magnesium alloy bearing cage, the numerical simulation was conducted on both filling and sollidification processes with finite element simulation software, and the optimal squeeze casting technological parameters were obtained. The simulation result shows that the optimized technological parameters are as follows. The casting temperature is 710℃, the preheating temperature for the die is 180 ℃, the shot speed is 25 mm/s, the specific pressure is 200 MPa, and the holding time is 20 s. In addition, the mathematical equations concerning the filling time, solidification time, preheating temperature and shot speed were established. And the visual obsevation on the filling and solidification processes of the molten alloy was performed. It is demonstrated that the filling and solidification processes of the magnesium alloy bearing cage are successful and reasonable, and the quality of the casting is good.