Embedded-atom potential for an accurate thermodynamic description of the iron–chromium system

• A new EAM interatomic potential for the iron–chromium system was developed.
• The metastable α/α′α/α′ phase diagram is described with high accuracy.
• Phonon excess entropies are found to be in good agreement with experiment.

A new potential for the iron–chromium (Fe–Cr) alloy system was optimized for the embedded-atom method (EAM) within the two-band model (TBM) extension. In contrast to previous works, free model parameters are predominantly adapted to available experimental high-temperature data of the mixing enthalpy. As a major improvement, the metastable α/α′α/α′ miscibility gap is accurately described in agreement with experimental data and a recent CALPHAD parametrization. The potential was also fitted to obtain an enriched solubility for chromium atoms in an iron matrix at 0 K, as it is predicted by several ab initio calculations. Furthermore, it was benchmarked against phonon excess entropies at 300 K and 1600 K demonstrating good agreement with respective results of inelastic neutron scattering.

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