About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Transmutation Effects in Materials in Fission, Fusion, and Spallation Environments
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| Presentation Title |
First-principles investigation of H/He synergistic effects in fcc Ni |
| Author(s) |
Kashi N. Subedi, Krishna Chaitanya Pitike, Giridhar Nandipati, David J Senor, Ayoub Soulami, Andrew M Casella |
| On-Site Speaker (Planned) |
Kashi N. Subedi |
| Abstract Scope |
In tritium-producing burnable absorber rods, neutron irradiation generates vacancies, self-interstitial atoms (SIAs), and transmutation gases such as H and He, which can interact and promote cavity formation in Nickel coating. In this work, we predict the thermodynamics of cavity formation using density functional theory. We quantify SIA–vacancy recombination thermodynamics for vacancies containing varying numbers of H and/or He atoms, and show how they modify defect recovery and vacancy-gas complex stabilization. To examine coupled H–He effects, we calculate binding energies of H and He in mixed H–He–vacancy complexes and assess gas accommodation within vacancy defects. We also map distance-dependent H–SIA and He–SIA binding energies to determine the spatial extent of gas–interstitial interactions. The resulting dataset will also be used to develop a Ni–H–He machine-learning potential to study thermodynamic and kinetic properties of wide range of gas-filled bubbles. |
| Proceedings Inclusion? |
Planned: |