Thermodynamic assessment of the Al-Nb system

The Gibbs energies of formation of the solution and compound phases in the Al-Nb system were derived from an optimisation procedure using all the available experimental thermodynamic and phase diagram data, The non-stoichiometric compounds were modelled with two or three sub-lattices, while a Redlich-Kister polynomial was used to describe the thermodynamic behaviour of the substitutional solutions, A consistent set of thermodynamic parameters with the phase diagram data is obtained.