Irradiation behavior of U-Nb-Zr alloy dispersed in aluminum

Three U-Nb-Zr alloys (U-5Nb-3Zr, U-6Nb-4Zr, and U-9Nb-3Zr) were included in a screening irradiation test of low-enrichment aluminum matrix dispersion fuels. Fuel particles made from these alloys reacted readily with aluminum during fuel fabrication and post-fabrication annealing, resulting in large fuel plate thickness increases. Under irradiation, the behavior of U-5N-b-3 Zr (wt%) alloy based fuel was poor at 41 at.% U-235 burnup, showing indicat ions of incipient breakaway swelling. The post-irradiation microstructural characteristics of U-6Nb-4Zr based fuel were somewhat better than those of U-5Nb-3Zr, but is marginal at 70 at.% burnup. U-Mo based fuels generally sh ow less reaction on fabrication and better fuel performance characteristics during irradiation. (C) 2001 Elsevier Science B.V. All rights reserved.