Optimization and calculation of the Fe-Ta phase diagram

An optimized set of thermodynamic functions was derived for the FeTa system from limited experimental information on phase equilibria and thermodynamics available in the literature using the conjugate gradient method. The thermodynamic properties of the ϵ-phase were described using the sublattice model. For the μ-phase, the enthalpy of formation was estimated from Miedema's model. A Redlich-Kister equation was used to describe the excess thermodynamic functions of the liquid, body-centred cubic and face-centred cubic phases. The phasediagram of the FeTa system was calculated from the evaluated thermodynamic data.