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 al l the available experimental thermodynamic and phase diagram data, The non-stoichiometric compounds were modelled with two or three sub-latt ices, while a Redlich-Kister polynomial was used to describe the therm odynamic behaviour of the substitutional solutions, A consistent set o f thermodynamic parameters with the phase diagram data is obtained.