About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Transmutation Effects in Materials in Fission, Fusion, and Spallation Environments
|
| Presentation Title |
Recent Insights into Helium Effects on Cavity Formation in Irradiated BCC Fe–Cr Alloys |
| Author(s) |
Yan-Ru Lin, Steven Zinkle |
| On-Site Speaker (Planned) |
Yan-Ru Lin |
| Abstract Scope |
BCC Fe–Cr alloys are promising structural materials for nuclear fission and fusion, but transmutation-helium effects on radiation-induced cavity evolution remain incompletely understood. This presentation highlights recent advances from dual-ion irradiated model alloys, nanostructured ferritic alloys, and neutron-irradiated Ni-doped F82H steels. Helium stabilizes vacancy clusters, accelerates bubble nucleation, and alters bubble/void size distributions. Cavity swelling varies non-monotonically with He production rate, peaking near the fusion-relevant rate of ~10 appm He/dpa, then decreasing at higher rates as over-nucleated small bubbles suppress void growth. Neutron irradiation confirms that fusion-relevant He production increases cavity density and contributes to hardening and embrittlement. In nanostructured alloys, nanoclusters trap He in dense, small bubbles, reducing swelling and limiting He diffusion to grain boundaries. Temperature-dependent cavity-denuded zones reveal distinct migration energies for vacancies and He–vacancy complexes. A generalized biased/unbiased sink-strength model improves swelling prediction, guiding radiation-tolerant Fe–Cr alloy design for nuclear applications. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Nuclear Materials, Characterization, Mechanical Properties |