Thermodynamic Properties of Al-Sc Alloys

Abstract

Mixing enthalpies of liquid binary Al–Sc alloys (0.62 < x_Sc < 1) are determined by isoperibolic calorimetry technique at 1840 K. The thermodynamic properties of liquid Al–Sc alloys are described in the entire composition range using the model of ideal associated solution. The thermodynamic activities of components of the Al–Sc melts demonstrate large negative deviations from the ideal behavior; the mixing enthalpies are characterized by significant exothermic effects. The minimum mixing enthalpy equals –32.7 ± 2.2 kJ/mol at x_Sc = 0.49. The experimental and literature data have been compared.