Recent studies using classical precipitation models to follow experimental precipitation kinetics in Al-Sc alloys had concluded that an explicitly time- and temperature-dependant interfacial energy must be adopted to explain the observed precipitation kinetics. An alternative explanation for the precipitation kinetics based upon vacancy-enhanced diffusivity was proposed here. This method, combined with a classical Kampmann–Wagner class model, permitted the reconciliation of the kinetics of nucleation, growth, and coarsening in an Al-Mg-Sc alloy using a single value for the interfacial energy in the range of 250 to 350C.

The Role of Excess Vacancies on Precipitation Kinetics in an Al-Mg-Sc Alloy. F.Fazeli, C.W.Sinclair, T.Bastow: Metallurgical and Materials Transactions A, 2008, 39[10], 2297-305