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Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
F. J. Homan, T. B. Lindemer, E. L. Long, Jr., T. N. Tiegs, R. L. Beatty
Nuclear Technology | Volume 35 | Number 2 | September 1977 | Pages 428-441
Performance and Performance Modeling | Coated Particle Fuel / Fuel | doi.org/10.13182/NT35-428
Articles are hosted by Taylor and Francis Online.
Two fuel failure mechanisms were identified for coated particle fuels that are directly related to fuel kernel stoichiometry. These mechanisms are thermal migration of the kernel through the coating layers and chemical interaction between rare-earth fission products and the silicon carbide (SiC) layer (the primary barrier to diffusion of metal fission products out of the particle) leading to failure of the SiC layer. Thermal migration appears to be most severe for oxide fuels, while chemical interaction is most severe with carbide systems. Thermodynamic calculations indicated that oxide-carbide fuel kernels may permit a stoichiometry that reduces both problems to manageable levels for currently planned high-temperature gas-cooled reactors. Such stoichiometry adjustment is possible over the complete spectrum from UO2 to UO2 for the present recycle fuel, a weak acid resin (WAR)-derived fissile kernel. Thermodynamic calculations indicate that WAR kernels containing <15% UC2 (>85% UO2) will develop excessive CO overpressures within the particle during irradiation. In 100% UO2 particles, thermal migration and oxidation of the SiC layer were observed after irradiation. The calculations also indicate that WAR kernels containing >70% UC2 (<30% UC2) contain insufficient oxygen to oxidize the rare-earth fission products formed in fuel operated to the maximum burnup levels of 75% fissions per initial metal atom (75% FIMA). Instead, the rare earths are present in part or completely as dicarbides. As such, they were observed to segregate from the kernel and collect at the SiC interface on the cold side of the particle, react with the SiC, and eventually fail this coating. Five WAR kernel stoichiometries were irradiated. These are either UO2 kernels, UO2 plus 15, 50, or 75% UC2, or 100% UC2. Results of these tests are consistent with thermodynamic calculations. Additional tests are in progress to establish the optimum stoichiometry; preliminary indications suggest an optimum value of ∼35% conversion with a permissible range of ±20%.
