基于CA方法的铝合金铸件微观组织的数值模拟

摘要

目前数值模拟技术已经成为预测铝硅合金铸件的凝固行为以及微观组织形成演化过程的重要工具.通过建立元胞自动机模型,在其中耦合FT-STAR软件计算的温度场和试验获得的形核参数,模拟了某型号铝硅合金铸件重力铸造条件下枝晶形核以及不同择优取向枝晶的生长过程.使用该模型预测了该铸件凝固过程关键点的晶粒度和二次枝晶臂,与试验结果吻合良好.%At present, numerical simulation technology has been an important tool to simulate the solidification behavior and microstructure evolution. Coupling the calculated temperature curve and experimental nucleated parameters, a cellular automaton (CA) model was developed to simulate the dendritic nucleation and growth with different preferred growth orientations of an aluminum-silicon alloy casting by gravity casting process. Using the CA model, the grain size and secondary dendrite arm spacing of some key points of the casting were predicted, which were in good agreement with the experimental results.