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DOE OSTI · 1846277

Grain boundary strain as a determinant of localized sink efficiency

Abstract

The opportunity to achieve radiation tolerance in crystalline materials hinges on understanding the structure and response of grain boundary sinks to irradiation. A common descriptor of grain boundary efficiency as a defect sink is the denuded zone, which is a defect free zone adjacent to the grain boundary dictated by its ability to absorb radiation induced defects. This descriptor is often used at the mesoscale, which requires an averaging of absorption events. In this paper, we resolve the defect sink efficiency as a function of interfacial strain with respect to grain boundary character, and correlate high levels of grain boundary strain to an enhanced absorption efficiency. Here, we also introduce a key relationship between localized strain in proximity with the grain boundary sink and the variation absorption efficiency associated with these regions, revealing the pitfalls of averaging absorption events along a grain boundary, and presenting a path forward toward improved models for denuded zones and localized grain boundary absorption phenomena.

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BibTeXRIS

Nathaniel, II, James E., Suri, Pranav K., Hopkins, Emily M., Wen, Jianguo, Baldo, Peter, Kirk, Marquis, Taheri, Mitra L.. 2022-01-08. Grain boundary strain as a determinant of localized sink efficiency. https://doi.org/10.1016/j.actamat.2022.117624

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36 MATERIALS SCIENCE↗