Calculation update! New properties have been added to the website for dislocation monopole core structures, dynamic relaxes of both crystal and liquid phases, and melting temperatures! Currently, the results for these properties predominately focus on EAM-style potentials, but the results will be updated for other potentials as the associated calculations finish. Feel free to give us feedback on the new properties so we can improve their representations as needed.
Warning! Note that elemental potentials taken from alloy descriptions may not work well for the pure species. This is particularly true if the elements were fit for compounds instead of being optimized separately. As with all interatomic potentials, please check to make sure that the performance is adequate for your problem.
Citation: K. Ito, T. Otaki, T. Yokoi, K. Hyodo, and H. Mori (2025), "Machine learning interatomic potential reveals hydrogen embrittlement origins at general grain boundaries in α-iron", Communications Materials7(1). DOI: 10.1038/s43246-025-01042-4.
Abstract: Hydrogen embrittlement accompanied by cracking along general grain boundaries (GBs), which are characterized by a lack of crystallographic symmetry, is a persistent challenge in developing high-strength structural alloys. We develop a highly accurate and transferable machine learning interatomic potential (MLIP) for Fe-H by acquiring comprehensive and efficient learning data via simultaneous learning. Our MLIP accurately describes the density functional theory results for various lattice defects in α-Fe and their interactions with hydrogen, general GBs with hydrogen segregation, and their deformation and fracture behavior. Large-scale molecular dynamics simulations reveal that hydrogen can suppress <111>/2 full dislocation emissions from general GBs and thereby potentially promote their fracture, supporting experimental suggestions. In contrast, for general GBs, where deformation twins are responsible for plasticity, the influence of hydrogen is minimal. This study contributes to the development of high-strength alloys by providing a robust MLIP construction methodology and new insights into hydrogen embrittlement mechanisms.