Evaluation of long-term exposure of 310S and 800H under conditions of SCW-SMR
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F26722445%3A_____%2F26%3AN0000003" target="_blank" >RIV/26722445:_____/26:N0000003 - isvavai.cz</a>
Result on the web
<a href="https://www.sciencedirect.com/science/article/pii/S0029549325008684" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0029549325008684</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1016/j.nucengdes.2025.114691" target="_blank" >10.1016/j.nucengdes.2025.114691</a>
Alternative languages
Result language
angličtina
Original language name
Evaluation of long-term exposure of 310S and 800H under conditions of SCW-SMR
Original language description
Austenitic stainless steels 310S and Alloy 800H are considered promising candidates for fuel cladding in Small Modular Reactors cooled by Supercritical Water due to their high corrosion resistance and favourable mechanical properties. To evaluate their long-term behaviour in supercritical water environments, full-length tube samples were exposed to supercritical water at 500 °C, 25 MPa, and 150 ppb dissolved oxygen for up to 10,000 h. Weight gain measurements revealed a decelerating oxidation rate over time, with low cumulative mass increases indicative of excellent corrosion resistance. Conservative extrapolation suggests that the wall penetration depth is projected to remain below 5 μm after 30,000 h for both alloys, supporting the expectation of long-term structural integrity. Surface roughness measurements corroborated these trends: 310S showed a gradual increase from 0.18 μm (as received) to 0.29 μm after 10,000 h, whereas 800H exhibited minimal change, attributed to its initially higher surface roughness. Post-exposure characterization by Scanning Electron Microscope with Energy-Dispersive X-ray Spectroscopy and Transmission Electron Microscope confirmed the formation of compact, chromium-rich oxide layers (Cr₂O₃) on both materials, with underlying Cr-depleted zones. Microstructural analysis revealed that 310S developed thicker oxide layer with larger grains and Cr-Ni-rich phases, whereas 800H exhibited finer oxide grains in a thinner layer, with occasional localized corrosion – nodules. These differences underscore the role of alloy composition in oxidation behaviour under supercritical water conditions. Overall, both 310S and 800H demonstrate excellent oxidation resistance and microstructural stability, reinforcing their applicability as fuel cladding materials in Small Modular Reactors cooled by Supercritical Water designs.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
20305 - Nuclear related engineering; (nuclear physics to be 1.3);
Result continuities
Project
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Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2026
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Nuclear Engineering and Design
ISSN
0029-5493
e-ISSN
1872-759X
Volume of the periodical
448
Issue of the periodical within the volume
March
Country of publishing house
CH - SWITZERLAND
Number of pages
12
Pages from-to
1-12
UT code for WoS article
001653860700001
EID of the result in the Scopus database
2-s2.0-105025665095