Mg-Zn-Si体系的相平衡计算及应用

Thermodynamic Calculation of Phase Equilibria in the Mg-Zn-Si System and Its Application

摘要:

利用Calphad方法重新评估了Mg-Si二元系的液相，并结合Mg-Zn和Zn-Si二元系热力学数据，外推得到Mg-Zn-Si三元系热力学参数；同时根据Mg2Si-MgZn2伪二元相图实验数据评估了Mg-Zn-Si系的液相三元相交互作用参数，计算相图与实验数据较一致。利用Scheil凝固模型模拟了Mg-2.33Zn-0.9Si(at%)合金的凝固过程，预测了镁合金在铸造冷却过程中的相演变信息，模拟计算结果与实验结果吻合较好

Abstract:

The liquid phase of the Mg-Si binary system was re-assessed by the Calphad approach. Combined the thermodynamic data of Mg-Zn and Zn-Si binary systems, the thermodynamic parameters of Mg-Zn-Si ternary system were obtained by extrapolation. Based on the phase diagram of Mg2Si-MgZn2 pseudo-binary system, the liquid ternary interaction parameters of Mg-Zn-Si system were assessed. The results show that the calculated phase diagram agrees basically with the experimental data. The solidification process of the Mg-2.33Zn-0.9Si (at%) alloy was simulated by Scheil model, and the phase evolution of Mg alloy during cooling casting was predicted. The results agree with the previous experiment results