Thermodynamic Properties of Al–Sc Alloys

The mixing enthalpies of liquid Al–Sc binary alloys (0.62 < xSc < 1) are determined by isoperibolic calorimetry at 1840 K. The thermodynamic properties of liquid Al–Sc alloys are described in the entire composition range using the ideal associated solution model. The thermodynamic activities of components in 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 xSc = 0.49. The experimental and literature data are compared.