Thermodynamic Properties of Alloys of the Binary Bi—Yb System

Abstract

The thermochemical properties of melts of the binary Bi—Yb system were studied by the calorimetry method over the concentration ranges 0 < x_Yb < 0.43 at 1000–1270 K and 0.8 < x_Yb < 1 at 1100–1140 K. It was shown that significant negative heat effects of mixing are characteristic features for these melts. A range 0 < x_Yb < 0.19 of the Bi—Yb phase diagram was investigated by the DTA method. Using the regular associated solution (RAS) model, the activities of components, Gibbs energies and the entropies of mixing in the alloys, and the phase diagram of this system were calculated. They agree with the data from literature.