Variation of sinterability with sintering atmosphere and Li2O addition for UO2-5wt%CeO2 mixed powder milled with different milling techniques

The variations of sinterability and microstructure were studied for UO2-5wt%CeO2 mixed powder by different milling techniques in terms of the atmosphere and Li2O-doping. When UO2-5wt%CeO2 powder milled with batch-type attrition mill was sintered at 1700 deg C in reducing atmosphere, sintered densities were above 95%T.D., but grain size distribution was inhomogeneous and both micrograin clusters of the size below 3μm and grains of about 8μm existed in sintered pellet. When UO2-5wt%CeO2 powder milled with two-stage continuous attrition mill was sintered at 1600 deg C and 1700 deg C in reducing atmosphere, grain size distribution was homogeneous and also micrograin clusters were not observed. When UO2-5wt%CeO2 powder was sintered in CO2 atmosphere or that doped with 0.1wt%Li2O was sintered in reducing atmosphere, grain size distribution was almost the same for both batch-type and two-stage continuous attrition mill