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arXiv · 2304.10120

Surface and in-depth structural changes in nuclear graphite irradiated with noble gases described with Raman imaging

Magdalena Gawęda·Magdalena Wilczopolska·Kinga Suchorab·Małgorzata Frelek-Kozak·Łukasz Kurpaska·Jacek Jagielski
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Abstract

4th Generation high-temperature gas-cooled nuclear reactors (HTGR) are regarded as possible sources of industrial heat in Poland and Europe, allowing for a substantial reduction of the dependency on gas and coal import. It is mainly due to their safety of use, reliability and economy in a current energetic crisis. In this work, graphite, as a primary construction material and neutron moderator in HTGR, was evaluated before and after ion irradiation since its properties depend on the material's structure and purity. Commercial graphite materials (IG-110, NBG-17) and the laboratory's in-home material were chosen for the exemplary samples. The structural damage in HTGR was simulated with energetic Ar+ and He+ ions with fluencies from 1E12 to 2E17 ion/cm2. Raman imaging was chosen to assess radiation damage build-up: the crystallites' evolution, occurrence and types of defects. The recorded evolution showed stronger disordering of the material with heavier Ar+ ions than with He+.

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Magdalena Gawęda, Magdalena Wilczopolska, Kinga Suchorab, Małgorzata Frelek-Kozak, Łukasz Kurpaska, Jacek Jagielski. 2023-04-20. Surface and in-depth structural changes in nuclear graphite irradiated with noble gases described with Raman imaging. https://doi.org/10.1016/j.nimb.2023.02.036

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