|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Thermal Property Characterization, Modeling, and Theory in Extreme Environments
||Oxidation Resistance Impact of Niobium and Zirconium Additions to U<sub>3</sub>Si<sub>2</sub>
||Geronimo Robles, Cole Moczygemba, Joshua T. White, Elizabeth Sooby
|On-Site Speaker (Planned)
U<sub>3</sub>Si<sub>2</sub> is a drop-in accident tolerant fuel candidate proposed for replacement of current UO<sub>2</sub> in light water reactors due to superior uranium density and thermal conductivity. These improvements facilitate deployment of advanced cladding materials carrying a higher neutronic penalty while also addressing non-proliferation, safety and performance concerns for the fuel. However, the energetic and pulverizing oxidation of U<sub>3</sub>Si<sub>2</sub> in off-normal, water bearing scenarios could lead to fuel liberation into the coolant in the event of cladding failure. Reported is the impact of corrosion resistant niobium (Nb) or protective oxide-forming zirconium (Zr) on the oxidation response of U<sub>3</sub>Si<sub>2</sub> in high temperature flowing steam. Compositions of U<sub>3</sub>Si<sub>2</sub> with up to 14 vol.% Nb or Zr were fabricated, heat treated, oxidized and characterized. Oxidation results of both as melted and heat-treated alloy additions are compared to the performance of unalloyed U<sub>3</sub>Si<sub>2</sub> via thermogravimetric analysis, scanning electron microscopy, and energy dispersive spectroscopy.