| About this Abstract |
| Meeting |
2023 TMS Annual Meeting & Exhibition
|
| Symposium
|
Composite Materials for Nuclear Applications II
|
| Presentation Title |
Ruthenium and Silver Diffusion in Nuclear Graphite |
| Author(s) |
Dina Elgewaily, Jacob Eapen |
| On-Site Speaker (Planned) |
Dina Elgewaily |
| Abstract Scope |
Nuclear graphite is used for neutron moderation as well as a fission product (FP) barrier in high-temperature gas-cooled reactors. A firm knowledge of FP diffusion mechanisms in graphite under normal and accident operational conditions is therefore important for reactor design. In this work, the diffusional characteristics of ruthenium and silver are investigated for five graphitic grades – AXF-5Q, ZXF-5Q, IG-110, NBG-18, and PCEA – for temperatures ranging from 500 to 900°C. Interestingly, two diffusional regimes, a fast region, and a slow region, can be identified. Surface characterization using electron microscopy reveals a transition from a spatially uniform surface coverage to a clustering behavior; this transition occurs between 700 to 800°C, approximately, for all the graphite grades. Concurrent Raman spectroscopy further corroborates this transitional behavior. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, Nuclear Materials, High-Temperature Materials |