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DOE OSTI · 2954827

Decoupling thermal and irradiation effects on grain boundary segregation

Thomas, Marie J. [Colorado School of Mines, Golden, CO (United States)]·Offidani, Daniele Fattó [University of Michigan, Ann Arbor, MI (United States)]·Dhoriya, Mohit [Clemson University, SC (United States)] (ORCID:0009000935156519)·Marquis, Emmanuelle A. [University of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000264762835)·Martinez, Enrique [Clemson University, SC (United States)]·Mathaudhu, Suveen N. [Colorado School of Mines, Golden, CO (United States)] (ORCID:0000000162485363)
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Abstract

Radiation-induced segregation (RIS) is most often measured by peak solute concentration at a boundary. However, this may give an incomplete picture of segregation quantity and phenomena. Radiation-induced and thermal segregation at grain boundaries was investigated in Fe-9.6 at.% Cr after 9 MeV Fe 3+ ion irradiation at 400 °C. The experimental results were compared to kinetic Monte Carlo (KMC) simulations. The study revealed that Cr enrichment (peak segregation) at the grain boundaries was comparable in both the irradiated and non-irradiated conditions, although irradiation resulted in broader segregation profiles in both experiments and simulations, indicating an overall increase in grain boundary segregation due to irradiation. This broadening is attributed to back diffusion into the grain interior. While it is an established phenomenon, this study offers a quantitative evaluation using experimental data and KMC modeling. Further, these results emphasize the importance of analyzing the entire segregation profile and decoupling the thermal and irradiation contributions to solute segregation.

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Thomas, Marie J. [Colorado School of Mines, Golden, CO (United States)], Offidani, Daniele Fattó [University of Michigan, Ann Arbor, MI (United States)], Dhoriya, Mohit [Clemson University, SC (United States)] (ORCID:0009000935156519), Marquis, Emmanuelle A. [University of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000264762835), Martinez, Enrique [Clemson University, SC (United States)], Mathaudhu, Suveen N. [Colorado School of Mines, Golden, CO (United States)] (ORCID:0000000162485363). 2025-11-11. Decoupling thermal and irradiation effects on grain boundary segregation. https://doi.org/10.1016/j.mtla.2025.102607

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