About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
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Metallic Fuels - Design, Fabrication, and Characterization
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| Presentation Title |
Compositional Effects on Phonon Dispersion and Lifetimes of U<sub>xTh<sub>1-xO<sub>2 using Inelastic X-Ray Scattering |
| Author(s) |
Puspa Upreti, saqeeb Adnan, Erika Nosal, Zilong Huwa, Sabin Regmi, Krzysztof Gofryk, J Matthew Mann, David H. Hurley, Marat Khafizov, Michael E Manley |
| On-Site Speaker (Planned) |
Puspa Upreti |
| Abstract Scope |
Uranium dioxide (UO<sub>2) and thorium dioxide (ThO<sub>2) are key nuclear fuel materials, with thermal transport playing a vital role in reactor efficiency and safety. Their shared crystal structure makes UO<sub>2-ThO<sub>2 solid solutions particularly interesting. Introducing magnetic U ion into diamagnetic ThO<sub>2 alters the thermophysical properties, with spin-lattice interactions potentially affecting phonon dominated thermal transport in ThO<sub>2. To probe the microscopic mechanism behind this behavior, we performed high-resolution inelastic X-ray scattering (IXS) measurements of phonon dispersion and lifetimes in U<sub>xTh<sub>1-xO<sub>2 single crystals (x = 0.13 and 0.5). Our analysis shows phonon interaction with magnetic excitations, revealing how U doping alters phonon energies and lifetimes. These insights advance our understanding of thermal transport and provide critical guidance for the development of the next generation nuclear fuel materials.
This work was supported by the US Department of Energy (DOE), office of Science, Energy Frontier Research Centers (EFRC), Center for thermal Energy Transport under Irradiation. |
| Proceedings Inclusion? |
Planned: |