摘要
High-entropy alloys (HEAs) are proposed as potential structural materials for advanced nuclear systems, but little is known about the response of matrix chemistry in HEAs upon irradiation. Here, we reveal a substantial change of matrix chemical concentration as a function of irradiation damage (depth) in equiatomic NiCoFeCr HEA irradiated by 3 MeV Ni ions. After ion irradiation, the matrix contains more Fe/Cr in depth shallower than ∼900-1000 nm but more Ni/Co from ∼900-1000 nm to the end of the ion-damaged region due to the preferential diffusion of vacancies through Fe/Cr. Preferential diffusion also facilitates migration of vacancies from high radiation damage region to low radiation damage region, leading to no void formation below ∼900-1000 nm and void formation around the end of the ion-damaged region at a fluence of 5 × 1016 cm-2 (∼123 dpa, displacements per atom, peak dose under full cascade mode). As voids grow significantly at an increased fluence (8 × 1016 cm-2, 196 dpa), the matrix concentration does not change dramatically due to new voids formed below ∼900-1000 nm.
源语言 | 英语 |
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页(从-至) | 1-13 |
页数 | 13 |
期刊 | Journal of Materials Research |
DOI | |
出版状态 | 已接受/待刊 - 2020 |
已对外发布 | 是 |