THERMODYNAMIC PROPERTIES OF TERNARY LIQUID ZINC-ALLOYS

The thermodynamic properties of zinc in the three ternary (Ag, Au, Cu) -Sn-Zn systems were measured with an emf method, and with the help of the Gibbs-Duhem equation the integral thermodynamic quantities of thes e three systems were calculated. In several binary systems (Sb-Zn, Au- Zn, Au-Sn) chemical short range order (CSRO) has been found in the mel t, which was confirmed by different experiments such as emf, electrica l conductivity, magnetic measurements, and calorimetry. It was therefo re of interest to investigate the change of the anomalies in the therm odynamic properties by the addition of a third element. The exact dete rmination of the thermodynamic functions of some of these alloys is al so of some importance for industrial applications. Since lead in solde r materials is a great environmental problem and a health concern it i s safer and more economical to replace lead in the solder materials in stead of cleaning up the waste. Some of these materials under consider ation are ternary tin alloys. For the ternary (Ag, Au, Cu)-Sn-Zn syste ms no information is available in the literature on the thermodynamic properties and on the phase diagram in the Sn-rich corner.