预测多元合金形成焓的三组元作用模型

研究了合金中的二元子系中的两组元的性质受到子系外组元的影响而引起形成焓的改变.模拟发现子系中组元的电负性和电子密度的改变与其和子系外组元电负性之和成比例，计算中可将此影响等效到对组元体积的影响，当子系外有多个组元时，其电负性的作用可等效到一个组元.对三元系合金形成焓的计算结果表明:考虑三个组元作用可大大提高预测的精度，结果与实验符合较好，优于几何模型预测结果.提出的合金形成焓建模的思路对于研究多元系合金的热力学性质也具有实际意义.

Three Component Interaction Model for Predicting the Formation Enthalpy of Multicomponent Alloys

The changes of the formation enthalpy of the system were investigated when the properties of any one component of a binary subsystem were affected by the component out of the subsystem. It was found from the simulation of the formation enthalpies of ternary alloys that the changes of the electronegativity and the electron density of one component of the binary subsystem were proportional to the sum of the electronegativity of both in and out of the subsystem. This effect could simply be taken into account in the calculation which was equivalent to the effect on the volume of the component. When more components existed out of the subsystem， the total contribution of their electronegativity could be equivalent to one component. It is shown from the calculation of the formation enthalpy of ternary alloys that the predicting results considering the effects of the three components were better than that using geometrical model and consistent with the experimental results. The method has great significance to the study of the thermodynamic properties of multicomponent system.