几种热力学模型应用于二元合金中各组元活度计算的研究

Modeling and Calculation of Activities of Constituent Elements in Binary Alloys

目前,大量二元系合金的活度计算模型得以广泛应用。本文以正规溶液模型,Miedema模型,MIVM,NRTL方程和Wilson方程作为研究模型,将各个模型所需参数进行统计,结果表明:NRTL方程和正规溶液模型所需参数最少,Miedema模型和MIVM所需参数较多,Wilson方程所需参数介于上述模型之间。通过计算Bi-Pb、Bi-Sn、Cd-Pb和Pb-Sn四个二元体系在全成分下的活度及相应活度的平均偏差S,得出:预测效果最好的是NRTL方程;Miedema模型的预测效果较差,其他模型的预测效果介于NRTL方程和Miedema模型之间。

The activities of the constituent elements in a variety of binary alloys were calculated with the widely used thermodynamic models,including but not limited to the regular solution model,Miedema model,molecular interaction volume model（ MIVM）,non-random two-liquid（ NRTL） equation and Wilson equation. The numbers of major parameters involved in each model were found to be in a descending order： Miedema model and MIVM Wilson equation NRTL equation and the regular solution model. The activities and average deviations of the alloys were calculated,such as the Bi-Pb,Bi-Sn,Cd-Pb and Pb-Sn alloys. The calculated results show that when it comes to prediction precision,NRTL equation does the best job and Miedema model does the worst.