Experimental studies of phase equilibria in high-temperature ternary immiscible metallic melts

Shear viscosity measurements were carried out for a liquid immiscible ternary system In–Se–Te in a temperature range from the monotectic to about 1200 K using an oscillating-cup viscometer. It was revealed that the ternary In₈₀Se_xTe_20−x (0 ⩽ x ⩽ 20 at.%) system may be considered as a set of quasibinary In–(Se/Te) alloys of almost critical concentrations. A variation of the Se to Te ratio at constant content of In changes the properties of coexisting liquids and affects the binodal temperature. The critical parameters describing the peculiarities of viscosity behavior in the vicinity of the critical point are evaluated. The analysis based on the dynamic theory of phase transitions for viscosity in the phase separation region is proposed. The results are compared with available data for immiscible dielectric solutions and metallic melts.