Activity Prediction by Modified Molecular Interaction Volume Model in Au-Sn Based Liquid Alloys

The Modified Molecular Interaction Volume Model (M-MIVM) was applied to predict component activities in Au-Sn based liquid alloys. Activity data from nine binary alloy systems (Au-Bi, Au-Cu, etc.) were fitted to predict activities in four ternary systems (Au-Bi-Sn, Au-Cu-Sn, Au-Sb-Sn, Au-Sn-Zn). M-MIVM demonstrated superior predictive capability over both the Molecular Interaction Volume Model (MIVM) and the Subregular Solution Model (SRSM), achieving highest fitting accuracy for binary systems and best experimental agreement for ternary systems. The model successfully constructed iso-activity curves for ternary Au-Bi-Sn liquid alloys at 800-1000 K.