|About this Abstract
||Materials Science & Technology 2020
||Ceramics in the Nuclear Fuel Cycle
||Nb and Ti Alloying Effects on the Phase and Oxidation of U<sub>3</sub>Si<sub>2</sub>
||Geronimo Robles, Joshua T. White, Elizabeth Sooby Wood
|On-Site Speaker (Planned)
U<sub>3</sub>Si<sub>2</sub> has been identified as an accident tolerant nuclear fuel candidate for light water reactors due to its superior thermal conductivity and increased uranium density, when compared to traditional uranium dioxide (UO<sub>2</sub>). While reducing internal thermal stresses and increasing efficiency with this improvement, U<sub>3</sub>Si<sub>2</sub> exhibits an energetic oxidation response less favorable than UO<sub>2</sub> during off normal and accident scenarios including coolant or steam exposure. To mitigate this, Ti and Nb were chosen as alloying constituents for their corrosion resistance and strength benefits when alloyed in materials like steels. The work presented investigates the response of alloyed U<sub>3</sub>Si<sub>2</sub> to water bearing atmospheres. Phase characterization of as-melted, thermally annealed and post oxidation compositions with up to 12 volume percent Nb and Ti by powder x-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy is reported. Included are select compositions in sintered pellet form. Thermogravimetric analysis conducted in flowing steam assesses oxidation resistance.
||Planned: At-meeting proceedings