Detection and analysis of particles with failed SiC in AGR-1 fuel compacts
As the primary barrier to release of radioactive isotopes emitted from the fuel kernel, retention performance of the SiC layer in tristructural isotropic (TRISO) coated particles is critical to the overall safety of reactors that utilize this fuel design. Most isotopes are well-retained by intact SiC coatings, so pathways through this layer due to cracking, structural defects, or chemical attack can significantly contribute to radioisotope release. In the US TRISO fuel development effort, release of 134Cs and 137Cs are used to detect SiC failure during fuel compact irradiation and safety testing because the amount of cesium released by a compact containing one particle with failed SiC is typically ten or more times higher than that released by compacts without failed SiC. Compacts with particles that released cesium during irradiation testing or post-irradiation safety testing at 1600–1800 °C were identified, and individual particles with abnormally low cesium retention were sorted out with the Oak Ridge National Laboratory (ORNL) Irradiated Microsphere Gamma Analyzer (IMGA). X-ray tomography was used for three-dimensional imaging of the internal coating structure to locate low-density pathways through the SiC layer and guide subsequent materialography by optical and scanning electron microscopy. In addition, all three cesium-releasing particles recovered frommore »
- Authors:
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- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Idaho National Lab. (INL), Idaho Falls, ID (United States)
- Publication Date:
- Grant/Contract Number:
- AC05-00OR22725
- Type:
- Accepted Manuscript
- Journal Name:
- Nuclear Engineering and Design
- Additional Journal Information:
- Journal Volume: 306; Journal Issue: C; Journal ID: ISSN 0029-5493
- Publisher:
- Elsevier
- Research Org:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Org:
- USDOE Office of Nuclear Energy (NE)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; TRISO; coated particle fuel; AGR; PIE
- OSTI Identifier:
- 1325503
- Alternate Identifier(s):
- OSTI ID: 1359679