THE EXCESS-ENTHALPIES OF LIQUID GE-PB-TE ALLOYS

The excess enthalpies of liquid alloys in the ternary system Ge-Pb-Te were determined at 1210 K in a heat flow calorimeter for five sections GeyPb1-y-Te with y = 0.2, 0.4, 0.5, 0.6 and 0.8 and at 1153 for Ge0.5 Pb0.5-Te. The enthalpy surface in the ternary system is determined by a valley of exothermic minima, stretching from an exothermic minimum a t the composition GeTe to one at the composition PbTe in the respectiv e binaries. The excess enthalpies in the timing metallic binary were a dapted with the Redlich-Kister formalism. For the description of the t hermodynamic functions in the ternary system the equation of Bonnier w as taken using ternary coefficients. The calculated curves are in good agreement with the experimental data.