About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Transmutation Effects in Fusion Reactor Materials: Critical Challenges & Path Forward
|
Presentation Title |
Investigation of High Temperature He Embrittlement Effects in High Performance Nickel-based Alloys |
Author(s) |
Zehui Qi, Steven Zinkle |
On-Site Speaker (Planned) |
Zehui Qi |
Abstract Scope |
For fusion and Gen IV reactor concepts operating at high temperatures and doses, high temperature He embrittlement (HTHE) might be the lifetime limit mechanism for potential structural materials. It is well accepted that tensile stress can dramatically enhance HTHE. However, limited creep test data during irradiation are available due to its drawback of high cost and long experimental time. In this context, an innovative specimen fixture was designed to provide tensile stress from zero to ~200 MPa during ion irradiation. We performed 4.5 MeV He^(2+) irradiations on 316 stainless steel, Fe-9Cr and three high-performance commercial Ni-based alloys at 650℃ and 750℃ with peak implanted He concentration of 200 appm for different stresses and He implantation rates. The size and number density of bubbles and cavities (matrix and grain boundary) were characterized by conventional TEM to quantify bubble behavior versus applied stress and He implantation rate for different matrix precipitate distributions. |
Proceedings Inclusion? |
Planned: |