U3Si2 behavior in H2O: Part I, flowing steam and the effect of hydrogen

Wood, Elizabeth Sooby; White, Joshua Taylor; Grote, Christopher John; Nelson, Andrew Thomas

doi:10.1016/j.jnucmat.2018.01.002

Title: U₃Si₂ behavior in H₂O: Part I, flowing steam and the effect of hydrogen

Journal Article · 17 January 2018 · Journal of Nuclear Materials

DOI: https://doi.org/10.1016/j.jnucmat.2018.01.002 · OSTI ID:1417827

Wood, Elizabeth Sooby ^[1]; White, Joshua Taylor ^[2]; Grote, Christopher John ^[2];

^[2]

The Univ. of Texas at San Antonio, San Antonio, TX (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Recent interest in U₃Si₂ as an advanced light water reactor fuel has driven assessment of numerous properties, but characterization of its response to H₂O environments is absent from the literature. The behavior of U₃Si₂ in H₂O containing atmospheres is investigated and presented in a two-part series of articles aimed to understand the degradation mechanism of U₃Si₂ in H₂O. Reported here are thermogravimetric data for U₃Si₂ exposed to flowing steam at 250–470 °C. Additionally the response of U₃Si₂ to flowing Ar-6% H₂ from 350 to 400 °C is presented. Microstructural degradation is observed following hours of exposure at 350 °C in steam. U₃Si₂ undergoes pulverization on the timescale of minutes when temperatures are increased above 400 °C. In conclusion, this mechanism is accelerated in flowing Ar-H₂ at the same temperatures.