THERMODYNAMIC PROPERTIES OF ZINC-RICH ZINC-ALUMINUM MELTS

A thermodynamic study of molten zinc-aluminum alloys in the range 450- degrees-C to 650-degrees-C and 0 to 0.43 atom fraction of aluminum was carried out by the electromotive force (emf) method using the reversi ble concentration cell W, pure Al \MgCl2-NaCl-KCl-AlCl3\ Zn-Al (1), W The activities of aluminum derived from the measured cell potentials s how considerable positive deviations from Raoult's law. The Henry's la w constants and the self-interaction parameters of aluminum were obtai ned from the experimental data for the dilute solutions. The activitie s of aluminum extrapolated from the present experimental data agree we ll with the data from the literature at 727-degrees-C. The values of r elative partial molar enthalpy and entropy are also consistent with th e results obtained by previous authors. The behavior of the alpha-func tion for aluminum indicates that the solution behaves approximately su bregularly in the dilute region over the temperature range investigate d, and regularly for atom fractions of aluminum greater than 0.1 at te mperatures greater than 550-degrees-C.