Thermodynamic properties of liquid Au-Bi-Sn alloys

► The thermodynamic data of the liquid ternary Au-Bi-Sn system are reported. ► The electromotive force method with a liquid electrolyte was used to determine the activity of tin in the alloys. ► The partial free energies of tin in this system were calculated from the obtained EMF values. ► The Gibbs-Duhem integration was used to calculate the integral Gibbs free energy and integral enthalpy in the system.