An Accurate Two-Body Interaction Model for Describing the Structure-Energy Relationship of Binary Alloys

Area of Science:

• Materials Science
• Computational Materials Science
• Alloy Physics

Background:

• Alloy properties are dictated by atomic structures, but systematic studies are hindered by a lack of efficient predictive tools.
• Understanding structure-property relationships is crucial for designing novel materials.

Purpose of the Study:

• To develop a quantitative model for the structure-energy relationship in binary transition metal alloys.
• To provide an accurate and efficient method for predicting alloy configuration stability.

Main Methods:

• Developed a two-body interaction model (2M-kNN) using first-principles density functional theory (DFT) calculations.
• Extracted interaction parameters from DFT energies of specific alloy configurations.
• Validated the model against machine learning potential and cluster expansion methods.

Main Results:

• The 2M-kNN model accurately predicts the relative stability of configurations in 57 body-centered cubic (bcc) and face-centered cubic (fcc) binary transition metal alloys.
• The model demonstrates comparable or superior accuracy to existing methods for binary alloys.
• Integration with Monte Carlo simulations provides short-range order patterns at various temperatures.

Conclusions:

• The 2M-kNN model offers a physically meaningful and accurate approach to understanding alloy structure-energy relationships.
• The model's energy extrapolation mechanism allows for DFT-level accurate total energy predictions of any supercell configuration.
• The framework shows potential for extension to multi-component alloys.