Stress-driven dynamic evolution of core-shell structured cavities with H and He in BCC-Fe under fusion conditions
Abstract
Understanding the dynamic behavior of microstructures formed under fusion conditions is critical for designing high-performance structural materials for fusion reactors. Under fusion conditions, cavities of core-shell structures are formed due to the interaction between irradiation-induced vacancies and H and He atoms produced via transmutation. In this study, thermodynamic analysis and molecular dynamics simulations are combined to investigate the atomic-scale mechanisms and dynamic response of core-shell cavities formed in BCC-Fe under applied stress/strain fields. The thermodynamic analysis provides both the foundational reference for cavity structures under fusion neutron irradiation and the initial configurations for atomistic simulations. Building on this framework, atomic-scale simulations demonstrate that H and He play a decisive role in the stress-strain response and the evolution of elastic-plastic deformation within the cavities. In core-shell configurations, H atoms serve a function analogous to that in He-filled cavities, synergistically interacting with He to induce cavity deformation under mechanical loading.
Cite
@article{arxiv.2603.00867,
title = {Stress-driven dynamic evolution of core-shell structured cavities with H and He in BCC-Fe under fusion conditions},
author = {Jin Wang and Fengping Luo and Yiheng Chen and Denghuang Chen and Bowen Zhang and Yuxin Liu and Guangyu Wang and Yunbiao Zhao and Sheng Mao and Mohan Chen and Hong-Bo Zhou and Jianming Xue and Yugang Wang and Chenxu Wang},
journal= {arXiv preprint arXiv:2603.00867},
year = {2026}
}