Interaction of the components in liquid glass-forming Fe–Hf–Ni alloys

Abstract

The enthalpies of mixing of liquid Fe–Hf–Ni alloys were studied at 1873 K by means of a high-temperature isoperibolic calorimeter. The investigations were performed along the section xFe/xNi = 3/1 at xHf = 0–0.18 and sections xFe/xNi = 1/1 and 1/3 at xHf = 0–0.46. The limiting partial enthalpies of mixing of undercooled liquid hafnium in liquid Fe–Ni alloys are (–135 ± 10) kJ mol−1 (at xFe/xNi = 3/1), (–155 ± 14) kJ mol−1 (at xFe/xNi = 1/1), and (–203 ± 15) kJ mol−1 (at xFe/xNi = 1/3). The integral mixing enthalpies are negative over the studied composition range. The integral mixing enthalpies show negative deviations from ideal mixing in the entire composition range. The thermodynamic properties of liquid ternary alloys are modeled using the associate solution model. The amorphization range in the ternary system is predicted by considering a total molar fraction of associates in undercooled liquid alloys.