振动过程的数值模拟在金属凝固中应用的研究进展

Progress on Numerical Simulation of Vibration in the Metal Solidification

将振动技术应用于金属凝固过程,既能有效改善凝固组织、提高铸件的性能,还具有成本低、节能环保的优点,因此振动技术在金属凝固中的应用得到了广泛的实验研究。但由于金属熔体的高温和不透明性阻碍了对它的测量和观察,振动对凝固影响的机理尚不完全清楚。数值模拟能够提供振动条件下流场、温度场、应力场等各个参量的变化规律,有助于更全面地理解振动的作用机理。同时,振动对金属凝固影响的数值模拟还未得到系统研究。本文介绍了振动技术在金属凝固中应用的数值模拟的研究进展,在振动方式上主要包括超声振动、机械振动及脉冲电磁场的数值模拟,在应用内容上主要包括熔体处理、充型、凝固、除杂及时效过程的数值模拟。系统地介绍了振动技术在铸造过程的各方面应用的数值模拟原理和技术的研究现状,同时对未来研究方向进行了展望。

The application of vibration technology to the metal solidification process can not only effectively improve the solidified structure and the performance of castings, but also have the advantages of low cost, energy saving and environmental protection. Therefore, the application of vibration technology in metal solidification has been extensively studied in experiments. However, due to the high temperature and opacity of the metal melt, hindering its measurement and observation, the mechanism how the vibration affects the solidification is not fully understood. Numerical simulation can provide the variation law of various parameters such as flow field, temperature field and stress field under vibration condition,which helps us understand the mechanism of vibration more thoroughly. Meanwhile, the numerical simulation of the influence of vibration on the solidification of metal melt has been much less systematically studied. This paper introduces the research progress of numerical simulation of vibration applied in metal solidification. The main vibration modes include ultrasonic vibration, mechanical vibration and pulsed electromagnetic vibration. The application mainly includes melt processing, filling, solidification, purification and ageing process of numerical simulation. The current research status of numerical simulation theoryand technology of vibration applied in all aspects of casting was summarized systematically. Furthermore, the future research directions of numerical simulation of vibration in metal solidification process were prospected.