Effects of MnO-Al2O3 on the Grain Growth and High-Temperature Deformation Strain of UO2 Fuel Pellets

RECYCLING PROCESS OF U3O8 POWDER IN MnO-Al2O3 DOPED LARGE GRAIN UO2 PELLETS

“…The pure UO 2 pellets and 950ppm of Mn and 50ppm of Al doped UO 2 pellets were prepared by a conventional sintering process [6]. The green pellets were sintered at 1730°C for 4h in a dry hydrogen atmosphere.…”

“…The recent development of fuel pellets for light water reactors is mainly focused on the large grain UO 2 pellets which could enhance pellet-cladding-interaction (PCI) behavior, because a large grain pellet is expected to enhance fuel plasticity at an elevated temperature of transient operation as well as the fission gas retention capability [1][2][3][4][5][6][7][8].…”

“…Among those, additives doping technology has been widely studied due to its effectiveness at increasing grain size and compatibility with an industrial pellet fabrication process [5][6][7][8]. MnO and Al2O 3 doped UO 2 pellets are being developed as a potential candidate for PCI solution by KAERI [6]. Previous out-of-pile test results [6] showed that the grain size and softness of UO 2 pellets could be enhanced by doping Mn and Al in UO 2 .…”

“…MnO and Al2O 3 doped UO 2 pellets are being developed as a potential candidate for PCI solution by KAERI [6]. Previous out-of-pile test results [6] showed that the grain size and softness of UO 2 pellets could be enhanced by doping Mn and Al in UO 2 . The average grain size of the UO 2 pellets could be enlarged by more than 50 µm by adding 1000 ppm of MnO-Al2O 3 additives mixture.…”

TiO2 doped UO2 fuels sintered by spark plasma sintering

“…To manipulate microstructure and obtain larger grain-sized UO 2 fuel pellets, oxide dopants were used as sintering additives [5][6][7][8][9][10] including TiO 2 [11,12], Cr 2 O 3 [13], Al 2 O 3 [14], and MgO [15] were studied with the focus on their effects on fission gas retention and fuel swelling in-pile performance. Unique features of oxide-doped fuels include greatly-enlarged grain size, as large as 100 µm, significantly larger than that of standard fuel (10-15 µm).…”