Ab-initio calculations of the formation energies of BCC-based superlattices in the FeAl system

Abstract

First-principles calculations of the total energies of A2 iron and aluminum, B2 (FeAl), B32 (FeAl) and D0 3 (Fe 3Al and FeAl 3) compounds were performed in the frame of density functional theory (DFT) using the Full Potential - Linear Augmented Plane Wave method (FP-LAPW). These results have been used to obtain formation energies of the respective ground states. The calculated formation energies of the D0 3 (Fe 3Al) and B2 (FeAl) compounds show excellent agreement with available calorimetric data on standard enthalpies of formation of FeAl alloys up to 50 at.% aluminum. As the FeAl system has a controversial magnetic behavior when described by ab-initio methods in the DFT, this agreement is remarkable.