The gallium-iron system: Enthalpy of formation in liquid state
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Through the use of a very high-temperature, automated calorimeter, the enthalpy of formation, ΔfH=f(XFe), of the Fe-Ga liquid system was measured in the temperature and molar fraction ranges 0<XFe< 0.591 and 1373 <T< 1573 whereT is inK. The molar enthalpies of formation of these liquid alloys are negative with an extremum point atXFe = 0.55 and ΔfH = -5.9 ± 0.6 kj/mol (all results are referred to the liquid state). From measurements performed on the Ga-rich mole fraction side, the limiting partial molar enthalpy was deduced Δhm0 (FeL in GaL) = -2 ± 0.2 kJ/mol. These results were compared with those obtained previously for the two similar systems, Ni-Ga and Co-Ga. Moreover a point of the liquidus line was obtained (XFe = 0.48 atT = 1466 K).
KeywordsEnthalpy Liquid Alloy Molar Enthalpy Liquid System Equilibrium Phase Diagram
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