Prediction of thermodynamic properties of the C-Fe-Co-Ni solid solutions by binary infinite dilute activity coefficients

A novel molecular interaction volume model proposed by the author can be used to describe the thermodynamic properties of a multicomponent solid solution system using its binary interaction parameters only. A derivation of the model for a common quaternary system has been shown as a compensation of its general expression. The predicted activity coefficients from the model are in good agreement with the experimental data of the C-Fe-Co-Ni solid solution. It shows that the model is of better predictability and reliability in comparison with a fourth-degree polynomial formulism because it has a good physical basis.