Abstract
Transmission electron microscopy observation of Kr bubble evolution in polycrystalline UO2 annealed at high temperature was conducted in order to understand the inert gas behavior in oxide nuclear fuel. The average diameter of intragranular bubbles increased gradually from 0.8 nm in as-irradiated sample at room temperature to 2.6 nm at 1600 °C and the bubble size distribution changed from a uniform distribution to a bimodal distribution above 1300 °C. The size of intergranular bubbles increased more rapidly than intragranular ones and bubble denuded zones near grain boundaries formed in all the annealed samples. It was found that high-angle grain boundaries held bigger bubbles than low-angle grain boundaries. Complementary atomistic modeling was conducted to interpret the effects of grain boundary character on the Kr segregation. The area density of strong segregation sites in the high-angle grain boundaries is much higher than that in the low angle grain boundaries.
| Original language | English |
|---|---|
| Pages (from-to) | 242-250 |
| Number of pages | 9 |
| Journal | Journal of Nuclear Materials |
| Volume | 496 |
| DOIs | |
| State | Published - Dec 1 2017 |
| Externally published | Yes |
Funding
This work was supported by the Laboratory Directed Research and Development program (LDRD project # 14-098 ) at Idaho National Laboratory. This work was also supported by the U.S. Department of Energy, Office of Nuclear Energy under DOE Idaho Operations Office Contract DE-AC07-051D14517 , as part of Nuclear Science User Facility experiments. X.M.B. acknowledges the financial support from the U.S. Department of Energy, Nuclear Energy University Program (# NE0008279 ) and Idaho National Laboratory , Faculty Joint Appointment Program, the Advanced Research Computing facilities at Virginia Tech, and the High Performance Computing facilities at Idaho National Laboratory. The authors would like to thank Jatuporn Burns, Yaqiao Wu, Joanna Taylor, and Kristi Moser-McIntire for their invaluable assistance at the Center for Advanced Energy Studies. The Kr implantation was accomplished in the Frederick Seitz Materials Research Laboratory Central Facilities at the University of Illinois-Urbana Champaign, and the authors would like to thank Doug Jeffers for this assistance in performing the irradiation. This manuscript was authored by a contractor (Battelle Energy Alliance, LLC) of the US Government under the Department of Energy Contract No DE-AC07-05ID14517. Accordingly, the US government retains and the publisher, by accepting the paper for publication, acknowledges that the US Government retains a nonexclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US Government purposes.
| Funders | Funder number |
|---|---|
| DOE Idaho Operations Office | DE-AC07-051D14517 |
| Idaho National Laboratory , Faculty Joint Appointment Program | |
| US Government | |
| U.S. Department of Energy | DE-AC07-05ID14517 |
| Battelle | |
| Office of Nuclear Energy | |
| Advanced Scientific Computing Research | |
| Nuclear Energy University Program | NE0008279 |
| Laboratory Directed Research and Development | 14-098 |
| Virginia Polytechnic Institute and State University | |
| Idaho National Laboratory |