Concentration dependencies of energy parameters in Fe–Al alloy

On the basis of X-ray data and the coherent potential approximation we show that interaction parameters for Fe–Al alloy strongly depend on the concentration. Calculation data for B2-phase for different concentrations are used to extract interaction parameters for partially ordered solid solutions and are compared with parameters treated from the diffuse X-ray scattering data. Importance of accounting for the concentration dependence of the parameter V(k→s), which is responsible for ordering tendency, is shown in the calculation of the critical temperature of order–disorder B2–A2 phase transition.