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Updated: Mar 31, 2026
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Structural γ-ε phase transition in Fe-Mn alloys from a CPA + DMFT approach
A S Belozerov1, A I Poteryaev, S L Skornyakov
1Miheev Institute of Metal Physics, Russian Academy of Sciences, 620137 Yekaterinburg, Russia. Ural Federal University, 620002 Yekaterinburg, Russia.
Summary
We developed a new computational method to study disordered alloys with strong electronic correlations. This method accurately predicts the structural transition temperature in iron-manganese alloys, showing electronic correlations are key.
Area of Science:
- Computational materials science
- Condensed matter physics
- Alloy theory
Background:
- Disordered alloys with strong electronic correlations present significant computational challenges.
- Understanding structural transformations in these materials is crucial for materials design.
- Previous methods struggled to accurately capture the role of electronic correlations in phase transitions.
Purpose of the Study:
- To develop and validate a novel computational scheme for total energy calculations in disordered alloys.
- To investigate the crucial role of electronic correlations in the structural transformations of Fe-Mn alloys.
- To accurately predict the γ-ε structural transition temperature in Fe-Mn alloys as a function of Mn content.
Main Methods:
- Coherent Potential Approximation (CPA) combined with Dynamical Mean-Field Theory (DMFT).
- Density Functional Theory (DFT) for material-specific Hamiltonians in the Wannier function basis.
- Application to paramagnetic Fe-Mn alloys with 10-20 at.% Mn.
Main Results:
- The computational scheme successfully captures the γ-ε structural transition in Fe-Mn alloys.
- Electronic correlations significantly influence the transition, with Coulomb interactions driving the decrease in transition temperature with increasing Mn content.
- Calculated transition temperatures show good agreement with experimental data.
Conclusions:
- The developed computational scheme provides a robust tool for studying disordered alloys with strong electronic correlations.
- The γ-ε transition in Fe-Mn alloys is driven by a interplay of kinetic and Coulomb energies, highlighting the importance of electron correlation effects.
- This work offers new insights into the mechanisms governing structural transitions in technologically relevant alloys.
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