About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Special Topics in Nuclear Materials: Reproducibility and Uncertainty; Hydrogen Effects; Space and Microreactor Systems
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| Presentation Title |
Hydrogen Retention in Zirconium Hydride Moderator: Atomistic Insights Into the Role of Microstructural Defect Sinks |
| Author(s) |
Jianqi Xi, Yuwen Xu, Wenwen Leng, Nicholas Dailey |
| On-Site Speaker (Planned) |
Jianqi Xi |
| Abstract Scope |
ZrH2-x is a promising candidate for neutron moderation in microreactors due to its high hydrogen content. However, its performance is limited by hydrogen loss at elevated temperatures. In this talk, we used atomistic simulations informed by a machine learning interatomic potential, we investigate hydrogen behavior in the presence of grain boundaries and triple junctions in hydrides. ZrH2 and ZrH1.75, are examined to capture the influence of hydrogen concentration on diffusion mechanisms. Our results show that grain boundaries significantly enhance hydrogen diffusivity in ZrH2, while their effects are mitigated in ZrH1.75 due to local variations in the H/Zr ratio. Elevated temperatures reduce diffusivity difference across grain boundary types. Our analysis reveals that grain boundaries do not serve as efficient hydrogen traps. We also explore the role of triple junctions in ZrH2-x and their impact on hydrogen trapping. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Modeling and Simulation, Nuclear Materials, High-Temperature Materials |