About this Abstract |
| Meeting |
Materials in Nuclear Energy Systems (MiNES) 2025
|
| Symposium
|
Materials in Nuclear Energy Systems (MiNES) 2025
|
| Presentation Title |
Investigating the Effect of Dose Rate on Cavity Evolution Using Ex-Situ and In-Situ Irradiation |
| Author(s) |
Xingyu Liu, Antoine Waegaert, Wei-Ying Chen, Arthur T. Motta, Xing Wang |
| On-Site Speaker (Planned) |
Xingyu Liu |
| Abstract Scope |
To expedite the qualification process of novel structure materials for advanced nuclear reactors, it is necessary to accelerate irradiation testing of advanced materials to high doses. Ion irradiation is a promising method for emulating neutron damage in nuclear reactors with significant time reduction. However, differences between neutron and ion irradiation, such as typical dose rates, cascade characteristics, and transmutation effects, can result in divergent microstructure evolution in materials. In this work, we compared swelling of austenitic 800H alloy irradiated by dual ions (Fe and He) and neutrons. We found that swelling in ion-irradiated samples did not exactly match that in neutron samples at high doses. To address this discrepancy, we combined ex-situ and in-situ ion irradiation to investigate cavity evolution across varying dose rates, with the idea that a lower dose rate may allow cavity shrinkage through cascade superposition. Ex-situ dual ion irradiation was performed at 7.5×10-4 dpa/s and 0.1 appmHe/dpa using 9 MeV Fe ions and 3.42 MeV energy-degraded He ions up to 32 dpa at 480°C to generate cavities. These cavities were further irradiated in situ at different dose rates ranging from 7.5×10-5 dpa/s to 7.5×10-4 dpa/s using 1 MeV Kr ions up to 1 additional dpa at 480°C. Transmission electron microscopy analysis revealed that cavity shrinkage did occur at higher dose rates, but the shrinkage was significantly suppressed under lower dose rates. The understanding of cavity stability at various dose rates can provide guidance for designing future ion irradiation experiments that more reliably emulate neutron-induced swelling. |
| Proceedings Inclusion? |
Undecided |