Thermodynamic properties of the Pb-Sb-Bi ternary system

The paper presents the results of the Pb-Sb-Bi ternary system thermodynamic study. Experimental data were obtained using the EMF method in the temperature range from 873 to 973 K. The alloys compositions related to the concentration triangle projections with ratios of antimony and bismuth mole fractions (N-Sb/N-Bi) equal to 1/3, 1 and 3, were studied. The values of partial molar(ex)Gibbs energy (Delta G(Pb)), entropy (Delta S-Pb), enthalpy (Delta H-Pb) and the corresponding excess characteristics (Delta G(Pb) and (Delta S-Pb) of lead in the binary and ternary liquid metal alloys were found using the optimized experimental dependencies of EMF (E-p) on lead mole fraction (N-Pb). The integral thermodynamic quantities were calculated using the Darken method. Isolines of integral excess Gibbs energy and entropy (Delta G(ex) and Delta S-ex), integral Gibbs energy, entropy and enthalpy (Delta G, Delta S and Delta H) for the Pb-Sb-Bi system are illustrated graphically. It is determined that Delta G(ex) and Delta S-ex values in the Pb-Bi-Sb ternary system at 973 K are small, which indicates a good miscibility of the studied system and the absence of a strong chemical interaction of the components. (C) 2019 Elsevier Ltd.