Predicting the Concentration Dependence of the Surface Tension of Ternary Systems

A comparative analysis of semi-empirical methods based on the Kohler, Bonnier, and Toop models for predicting the surface tension (ST) of ternary systems has been performed. Surface tension–concentration dependence calculations have been carried out in the indium–tin–lead and indium–tin–gallium systems. The ternary indium–tin–lead system is characterized by the fact that the excess surface tension isotherms of all the side binary melts are symmetrically shaped with respect to the equimolar composition, and such systems are called symmetric. In the ternary indium–tin–gallium system, the excessive surface tension isotherms of side binary indium–gallium and tin–gallium systems have pronounced asymmetry with respect
to the equimolar composition, and such systems are called asymmetric. It has been shown that a method based on the Kohler model rather precisely describes the concentration dependence of the surface tension of
symmetric ternary systems. However, this method does not predict the concentration dependence of the surface tension of asymmetric systems. It has been revealed that the Bonnier and Toop models can predict the
surface tension–concentration dependence for asymmetric ternary systems with strong asymmetry in the excess surface tension isotherms of two side binary systems independently of the degree of complexity in these isotherms within overall error of experiment.