Universal machine learning interatomic potentials poised to supplant DFT in modeling general defects in metals and random alloys

TL;DR

This paper demonstrates that advanced pretrained universal machine learning interatomic potentials can accurately and efficiently model complex defects in metals and alloys, potentially replacing DFT calculations in materials research.

Contribution

The study introduces state-of-the-art uMLIPs that achieve DFT-level accuracy across diverse defect scenarios, outperforming existing ML potentials and emphasizing the importance of diverse datasets and architectures.

Findings

uMLIPs achieve RMSE below 5 meV/atom for energies

uMLIPs outperform specialized ML potentials

Data diversity is crucial for accurate defect modeling

Abstract

Recent advances in machine learning, combined with the generation of extensive density functional theory (DFT) datasets, have enabled the development of universal machine learning interatomic potentials (uMLIPs). These models offer broad applicability across the periodic table, achieving first-principles accuracy at a fraction of the computational cost of traditional DFT calculations. In this study, we demonstrate that state-of-the-art pretrained uMLIPs can effectively replace DFT for accurately modeling complex defects in a wide range of metals and alloys. Our investigation spans diverse scenarios, including grain boundaries and general defects in pure metals, defects in high-entropy alloys, hydrogen-alloy interactions, and solute-defect interactions. Remarkably, the latest EquiformerV2 models achieve DFT-level accuracy on comprehensive defect datasets, with root mean square errors (RMSE) below 5 meV/atom for energies and 100 meV/{\AA} for forces, outperforming specialized machine learning potentials such as moment tensor potential and atomic cluster expansion. We also present a systematic analysis of accuracy versus computational cost and explore uncertainty quantification for uMLIPs. A detailed case study of tungsten (W) demonstrates that data on pure W alone is insufficient for modeling complex defects in uMLIPs, underscoring the critical importance of advanced machine learning architectures and diverse datasets, which include over 100 million structures spanning all elements. These findings establish uMLIPs as a robust alternative to DFT and a transformative tool for accelerating the discovery and design of high-performance materials.