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arXiv · 2411.18906

Short-Range Order Based Ultra Fast Large-Scale Modeling of High-Entropy Alloys

Abstract

High-Entropy Alloys (HEAs) exhibit complex atomic interactions, with short-range order (SRO) playing a critical role in determining their properties. Traditional methods, such as Monte Carlo generator of Special Quasirandom Structures within the Alloy Theoretic Automated Toolkit (ATAT-mcsqs), Super-cell Random Approximates (SCRAPs), and hybrid Monte Carlo-Molecular Dynamics (MC-MD) are often hindered by limited system sizes and high computational costs. In response, we introduce PyHEA, a Python-based toolkit with a high-performance C++ core that leverages global and local search algorithms, incremental SRO computations, and GPU acceleration for unprecedented efficiency. When constructing random HEAs, PyHEA achieves speedups exceeding 133,000x and 13,900x over ATAT-mcsqs and SCRAPs, respectively, while maintaining high accuracy. PyHEA also offers a flexible workflow that allows users to incorporate target SRO values from external simulations (e.g., LAMMPS or density functional theory (DFT)), thereby enabling more realistic and customizable HEA models. As a proof of concept, PyHEA successfully replicated literature results for a 256,000-atom Fe-Cr-Co system within minutes-an order-of-magnitude improvement over hybrid MC-MD approaches. This dramatic acceleration opens new possibilities for bridging theoretical insights and practical applications, paving the way for the efficient design of next-generation HEAs.

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BibTeXRIS

Caimei Niu, Lifeng Liu. 2025-01-09. Short-Range Order Based Ultra Fast Large-Scale Modeling of High-Entropy Alloys. https://arxiv.org/abs/2411.18906

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