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DOE OSTI · 1778921

Advanced Microscopy Report on UCO Fuel Kernels from Selected AGR-1 and AGR-2 Experiments

Van Rooyen, Isabella J·Yang, Yong·Fu, Zhenyu·Kombaiah, Boopathy·Wright, Karen E
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Abstract

A variety of neutron irradiation experiments were completed at Idaho National Laboratory (INL) on tristructural isotropic (TRISO) coated particles contained in a graphitic matrix as part of the Advanced Gas Reactor (AGR) fuel development and qualification program. Although the initial advanced microscopy and microanalysis studies on AGR-1 particles focused predominantly on the SiC layer?s role as the main fission-product containment, studies were further expanded to evaluate UCO kernels of selected AGR-1 and AGR-2 coated particles. Fuel kernels tested in the AGR-1 and AGR-2 experiments is composed of a mixture of UO2 and UC, with a nominal as-fabricated stoichiometry of UO1.37 C0.35 and UO1.43 C0.39, respectively. These as-fabricated kernel-stoichiometry values are determined at the completion of kernel fabrication and do not account for any changes that will occur during the subsequent coating and compacting processes.

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11 NUCLEAR FUEL CYCLE AND FUEL MATERIALSAdvanced Gas ReactorPost-irradiation examinationTristructural Isotropic

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Van Rooyen, Isabella J, Yang, Yong, Fu, Zhenyu, Kombaiah, Boopathy, Wright, Karen E. 2021-03-29. Advanced Microscopy Report on UCO Fuel Kernels from Selected AGR-1 and AGR-2 Experiments. https://www.osti.gov/biblio/1778921

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