Work

Irradiation-Induced Grain Growth of γ F e 2 O 3 and F e 3 O 4 at Cryogenic Temperatures

Year: 2026

Type: article

Abstract: This work reports the first observations of grain growth under irradiation of Fe oxides, specifically maghemite (γ-Fe 2 O 3 ) and magnetite (Fe 3 O 4 ). The Fe oxide thin films were grown by Pulsed Laser Deposition and irradiated in-situ in a Transmission Electron Microscope at − 223 ∘ C using 1 MeV Kr 2+ ions up to 8.75 x 10 19 ions / m 2 to study grain growth kinetics under irradiation. Grain growth at such low temperatures appears to follow kinetics that can be accounted for by the thermal spike model developed for metals in the literature. The corresponding activation energies were calculated and compared with other oxides. The results demonstrate that γ-Fe 2 O 3 , despite its larger initial grain size, exhibits surprisingly fast grain growth in comparison with Fe 3 O 4 , likely due to the presence of iron vacancies in the crystal structure that facilitate faster atomic diffusion under irradiation.

Source: Scripta Materialia

DOI: 10.1016/j.scriptamat.2026.117179

Authors: Dmitrii Kretov, Tiffany Kaspar, Ben Derby, Daniel Schreiber, Djamel Kaoumi

Institutions: North Carolina State University, Pacific Northwest National Laboratory, Los Alamos National Laboratory

Language: English

Topic: Fusion materials and technologies

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,220

Funders: U.S. Department of Energy, Office of Science, Basic Energy Sciences