Thermodynamics of Oxygen and Sulfur in Ternary Liquid Alloys

The Margules equation is used in interpreting the excess Gibbs energies of several ternary systems. In the present study the activity coefficient of a dilute solute, 2, in a binary solvent 1-3 is interpreted using the Margules equation for a ternary system. The formalism is based on Gibbs energy interaction parameters which is deduced from the integral function of a ternary system. The derived expression is used to interpret logarithmic activity coefficient of oxygen in seven metallic systems and of sulfur in three metallic systems. The present study calculations of logarithmic activity coefficient of solute are compared with the available experimental data. Self interaction parameters of the solutes are derived from the partial functions of solutes along the constant compositional path. A thermodynamic formalism based on Maclaurin infinite series is used in interpreting excess Gibbs energy of a ternary system. An expression for logarithmic activity coefficient and self-interaction parameter of oxygen were derived using Maclaurin infinite series equations using same conditions as mentioned for the Margules equations. The derived equations are based on Maclaurin infinite series used successfully to deduce the thermodynamics of self-interaction of oxygen as a interstitial atom in two metallic systems. The predicted thermodynamic parameter values using Maclaurin Corresponding author infinite series and Margules equations, were found to be in excellent agreement with the available experimental data and also our predictions are far more accurate than the predictions made by other models.