Microstructural and crystallographic effects of sol-gel synthesized Ti-doped UO2 sintered under reducing conditions.
- Resource Type
- Article
- Authors
- Silva, Chinthaka M.; Hunt, Rodney D.; Nelson, Andrew T.
- Source
- Journal of Nuclear Materials. Aug2021, Vol. 552, pN.PAG-N.PAG. 1p.
- Subject
- *URANINITE
*HEAT treatment
*MICROSPHERES
*LATTICE constants
*CRYSTAL grain boundaries
*ELECTRON microscopy
*GELATION
- Language
- ISSN
- 0022-3115
Titanium (Ti)-doped UO 2 microspheres of three different Ti concentrations (1000, 2000, and 4000 wppm) were synthesized using an internal gelation process. The microspheres were pressed into pellets, and a two-step heat treatment was applied to form monolithic cylindrical pellets with high densities (≥95%TD). Microstructure of these samples consisted of equiaxed grains with >300% increase in average grain size compared to the undoped UO 2 pellets. Secondary Ti-rich chemical phases corresponding to a liquid eutectic formed during sintering were observed at grain boundaries of UO 2 for samples doped with 4000 wppm Ti. These Ti-rich chemical phases were not observed in 1000 or 2000 wppm Ti samples at microscale using electron microscopy investigations. The 0.02–0.04% lower lattice parameter values for the Ti-doped UO 2 samples compared to the undoped UO 2 confirms the incorporation of Ti into the UO 2 lattice. [ABSTRACT FROM AUTHOR]