Synthesis and Characterization of UO₂ Feedstocks containing Controlled Dopants

Technical Report · Tue Jan 01 04:00:00 EST 2019

DOI:https://doi.org/10.2172/1495946· OSTI ID:1495946

Finkeldei, Sarah ^[1]; Hunt, Rodney Dale ^[1]; Kiggans Jr, James O. ^[1]; Hobbs, Christopher A. ^[1]; Eckhart, Brian D. ^[1]; Mcmurray, Jake W. ^[1]; Brown, Daniel ^[1]; Helmreich, Grant W. ^[1]; Terrani, Kurt A. ^[1]; Nelson, Andrew ^[1]

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1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Within the Advanced Fuels Campaign, the Oak Ridge National Laboratory is looking into the fabrication of high-performance UO₂ fuel candidates. The aim of this study was to develop a suitable fabrication avenue to synthesize UO₂ feedstock with controlled dopants to enhance UO₂ grain growth within these fuel candidates. Enlarged UO₂ grains in a nuclear fuel pellet are expected to slow down fission gas diffusion, which would be a preferred property for a high-performance fuel compared to fission gas diffusion in standard UO₂. The unique fabrication processes for microspherical feedstocks via the internal gelation approach at the Oak Ridge National Laboratory have been developed further to enable the dopant uptake within the UO₂ microspheres. Mn and Cr were added via infiltration and/or addition of the dopant to the starting broth of an internal gelation experiment. The dopants were added in various amounts (ppm) into UO₂. Even though large amounts of these dopants volatized during sintering, scanning electron microscopy images of the microstructure revealed large UO₂ grains of up to 80 μm for the pellets that were prepared from doped microspherical feedstocks.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1495946
• Report Number(s): ORNL/SPR-2019/1067
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS