A reference-free MEAM potential forα-Fe andγ-Fe.

Area of Science:

• Materials Science
• Computational Materials Science
• Condensed Matter Physics

Background:

• Accurate interatomic potentials are essential for molecular dynamics simulations of materials.
• Existing potentials may not adequately capture the complex behavior of iron phases, especially within critical temperature ranges for steel processing.
• The embedded atom method (EAM) and its modifications are widely used for modeling metallic systems.

Purpose of the Study:

• To develop and validate a novel reference-free modified embedded atom method (RF-MEAM) potential for iron.
• To enable accurate prediction of both body-centered cubic (bcc, α-Fe) and face-centered cubic (fcc, γ-Fe) lattice properties.
• To facilitate simulations of iron phase transformations and related phenomena in the 800-1300 K temperature range.

Main Methods:

• Construction of a reference-free modified embedded atom method (RF-MEAM) potential for iron.
• Validation against established experimental and computational data for lattice properties.
• Comparison with existing (M)EAM potentials commonly employed in molecular dynamics simulations.
• Assessment of the potential's performance in predicting point defect, surface, and stacking fault energies.

Main Results:

• The developed RF-MEAM potential accurately reproduces bcc and fcc iron lattice properties.
• It demonstrates excellent agreement with experimental data in the critical 800-1300 K temperature range.
• The potential shows superior performance in predicting point defect, free surface, and stacking fault energies compared to other potentials.
• Nishiyama-Wassermann and Kurdjumov-Sachs orientation relationships and interface energies for α-Fe/γ-Fe interphases are well reproduced.

Conclusions:

• The new RF-MEAM potential offers a significant advancement for simulating iron and steel behavior.
• It provides a reliable tool for molecular dynamics simulations, particularly for phase transformations in steel.
• The potential's compatibility with standard simulation software like LAMMPS enhances its practical applicability.