基于CAFE模拟Cu-3Ni-0.96Si-0.15Mg合金的铸锭凝固组织演变

Simulation of Ingot Solidification Microstructure Evolution of Cu-3Ni-0.96Si-0.15Mg Alloy Based on CAFE

采用ProCast软件中CAFE(元胞自动机有限元法)模型模拟计算了Cu-3Ni-0.96Si-0.15Mg铸锭凝固过程中枝晶生长组织演变过程,并将预测的凝固组织与实验微观组织进行了对比,验证了模型的准确性。结果表明,模拟预测的凝固组织与实验基本一致,说明该模型可以很好地模拟实际凝固组织。然后,利用此模型模拟研究了过热度以及形核密度对铸锭凝固组织的影响。结果表明:增大形核率以及适当降低浇注温度可以明显细化晶粒,提高等轴晶区的占比,当过热度为20℃,最大形核密度为1×10^(9)m^(-3)时,铸锭凝固组织几乎为等轴晶组织,其等轴晶区占比达到92.34%。

CAFE(cellular automaton finite element method)model in ProCast software was used to simulate and calculate the dendrite microstructure evolution during solidification of Cu-3Ni-0.96Si-0.15Mg ingot,and the predicted solidification microstructure was compared with the experimental microstructure to verify the accuracy of the model.The results show that the solidified microstructure predicted by the simulation is basically consistent with the experiments,indicating that the model can simulate the actual solidified microstructure very well.Then,the effect of the overheat temperature and the nucleation density on the ingot solidification microstructure was studied.The results show that increasing the nucleation rate and reducing the pouring temperature can obviously refine grain size.When the overheat temperature is 20℃and the maximum nucleation density is 1×10^(9)m^(-3),the solidification structure of the ingot is almost the equiaxed grain structure,and the ratio of the equiaxed grain zone is about 92.34%.