b'Accomplishments: and some aggregates were biggerFigure 1. Microstructures of FS CeO2 Nanopowders of CeO 2and UO 2 than 5 m. Even though FS is a very(left) and UO 2(right) pellets made with were synthesized in-house withfast sintering technique capable ofin-house synthesized powder. CeO 2average grain size is 1.4 m, while UO 2nanoparticles smaller than 3 nm, andretaining small grain sizes, the finalmicrostructure shows the formation of then pellets of these materials weremicrostructure is dictated by themicron-sized crystalsfabricated via FS. The microstructuresmorphology of the powder precursor. of FS CeO 2and UO 2pellets are shownMoreover, attempts to produce sim HBS in Figure 1. CeO 2pellets made by FSof UO 2using FS led to the formation retained an average grain size of 1.4of micron-sized UO 2crystals inside m and were densified up to 75.7%the FS pellets, as presented in Figure TD, while keeping an open porosity1. It is possible that the contamination of 19%. These results are close to whatby organic materials of the in-house is observed in actual HBS, which aresynthesized powder combined with the characterized by submicron grainselectric current and oxygen deficient smaller than 0.7 m, and porositiesatmosphere during FS led to the reduc-higher than 15 vol.%. To reduce thetion of the stoichiometry of the mate-grain sizes of sim HBS even further, itrial. If UO 2-xwas formed during FS, it is necessary to reduce the nanopowdercould then melt at low temperatures agglomeration and aggregation. The(1132 C), inducing the formation of in-house synthesized CeO 2powderUO 2crystals and of UC phase, as later had agglomerates bigger than 50 midentified by X-ray diffraction.2021|AFC ACCOMPLISHMENTS 23'