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Title: Synthesis and sintering of UN-UO2 fuel composites

In this study, the design and development of an economical, accident tolerant fuel (ATF) for use in the current light water reactor (LWR) fleet is highly desirable for the future of nuclear power. Uranium mononitride has been identified as an alternative fuel with higher uranium density and thermal conductivity when compared to the benchmark, UO2, which could also provide significant economic benefits. However, UN by itself reacts with water at reactor operating temperatures. In order to reduce its reactivity, the addition of UO2 to UN has been suggested. In order to avoid carbon impurities, UN was synthesized from elemental uranium using a hydride-dehydride-nitride thermal synthesis route prior to mixing with up to 10 wt% UO2 in a planetary ball mill. UN and UN – UO2 composite pellets were sintered in Ar – (0–1 at%) N2 to study the effects of nitrogen concentration on the evolved phases and microstructure. UN and UN-UO2 composite pellets were also sintered in Ar – 100 ppm N2 to assess the effects of temperature (1700–2000 °C) on the final grain morphology and phase concentration.
 [1] ;  [1] ;  [1] ;  [1] ;  [2] ;  [3] ;  [4] ;  [4] ;  [1]
  1. Boise State Univ., Boise, ID (United States); Center for Advanced Energy Studies, Idaho Falls, ID (United States)
  2. Univ. of Wisconsin-Madison, Madison, WI (United States)
  3. Idaho National Lab. (INL), Idaho Falls, ID (United States)
  4. Westinghouse Electric Company, LLC, Pittsburgh, PA (United States)
Publication Date:
OSTI Identifier:
Report Number(s):
Journal ID: ISSN 0022-3115; PII: S002231151530057X
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Nuclear Materials
Additional Journal Information:
Journal Volume: 466; Journal Issue: C; Journal ID: ISSN 0022-3115
Research Org:
Idaho National Laboratory, Idaho Falls, ID (United States)
Sponsoring Org:
Country of Publication:
United States
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS uranium nitride; composite fuel; nuclear fuel