电磁离心凝固过程中宏观偏析的数值模拟

基于连续模型建立了非惯性坐标系下电磁离心凝固过程流动、传热、传质耦合数学模型．依此模型对Al-5％Cu合金进行了模拟计算．结果表明，电磁离心凝固过程中，电磁力使熔体的平均径向运动速度下降．熔体流动状态的改变使凝固合金外层的逆偏析减轻，凝固过程中两相区的负偏析也减轻．与普通离心铸造相比，电磁离心凝固可减轻铸件宏观偏析．模拟结果与实测铸件成分分布基本吻合，表明本数学模型较好地描述了电磁离心凝固过程．

Numerical Simulation of Macrosegregation During Electromagnetic Centrifugal Solidification

A macrosegregation model, based on the continuum formulation, is developed to evaluate momentum, heat and mass transfers during electromagnetic centrifugal solidification. Using a non-inertial coordinate system, the model is applied to predict Al-5%Cu alloy solidification under electromagnetic centrifugal solidification. The results show that the effect of electromagnetic force on melt lowers the radial component velocity of melt flow. The change of melt flow decreases the inverse segregation at outer position of the solidifying alloy and the negative segregation at the mushy zone. Electromagnetic centrifugal solidification lessens marcogregation compared with conventional centrifugal casting. Good agreement is found between the simulation and experiment results, which shows the electromagnetic centrifugal solidification can be described well by this model.