A procedure for calculation of three-phase equilibria with the participation of gas in binary systems

A model for calculation of three-phase equilibria with the participation of gas in binary systems is suggested and analyzed. This model is based on the joint solution of equations of the temperature and concentration dependences of the activity of components in solutions and liquidus equations in the T-x phase diagrams. Comparison calculated and experimental data by the location of the curves of three-phase equilibria α ⇆ L ⇆ G in the p-T phase diagrams of the Au-Cd and Cu-Zn systems confirmed the actuality of previous assumptions and the adequacy of the model suggested. The computing model is used to determine the parameters of extreme points in the curves of three-phase equilibria α ⇆ L ⇆ G of certain systems with the participation of metals.