| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
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Microstructural, Mechanical, and Chemical Behavior of Solid Nuclear Fuel and Fuel-Cladding Interface II
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| Presentation Title |
Stability of the U-Zr δ-Phase |
| Author(s) |
Michael T. Benson, Tiankai Yao, Mukesh Bachhav, Chao Jiang, Jennifer Watkins, Joshua Zelina |
| On-Site Speaker (Planned) |
Michael T. Benson |
| Abstract Scope |
The U-Zr phase diagram has been essentially unchanged since 1956, with only minor modifications, primarily adjustments to the transition temperatures, incorporated since. During this time, the phase diagram has guided nuclear fuel development, as the behavior of U-10 wt. % Zr as a fuel is very dependent upon microstructure. The two primary phases present are α-U and δ-UZr<sub>2</sub>, the only intermetallic compound in this system. Important properties include swelling, solidus/liquidus temperatures, and fission product solubilities. Scanning electron microscopy, transmission electron microscopy, X-ray diffractometry and atom probe tomography results will be presented for a series of 500 °C annealing experiments conducted up to and including one year, along with density functional theory modeling. The results show that δ-UZr<sub>2</sub> is not a thermodynamically stable intermetallic compound and will separate into U and Zr. δ-UZr<sub>2</sub> is a long-lived metastable phase, and the breakdown is kinetically slow. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Nuclear Materials, Characterization, Modeling and Simulation |