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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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New coolants, new fuels: A new generation of university reactors
Here’s an easy way to make aging U.S. power reactors look relatively youthful: Compare them (average age: 43) with the nation’s university research reactors. The 25 operating today have been licensed for an average of about 58 years.
D. P. Harmon, C. B. Scott
Nuclear Technology | Volume 35 | Number 2 | September 1977 | Pages 343-352
Performance and Performance Modeling | Coated Particle Fuel / Fuel | doi.org/10.13182/NT77-A31894
Articles are hosted by Taylor and Francis Online.
Properties affecting the irradiation performance of outer pyrolytic carbon (PyC) layers on Triso- and Biso-coated fuel particles were studied. Irradiation temperatures were 1000 to 1500°C (1273 to 1773 K). Fast-neutron fluences reached 12.4 × 1025 n/m2 (E > 29 fJ)HTGR, which is 55% beyond the large high-temperature gas-cooled reactor peak design exposure of 8.0 × 1025 n/m2. Coatings with densities between 1.85 and 1.95 Mg/m3 and mean optical anisotropy values of ≤1.03 (BAF0 units) exhibited the best irradiation performance on Triso particles. For Biso particles, it is necessary to deposit the outer layer at coating rates between 3 and 8 µm/min and with densities ≥1.84 Mg/m3 to produce coatings impermeable to fission gases after irradiation. Data from fuel rod tests show that it is important to limit the degree of surface-connected porosity of the outer PyC layer and the amount of binder phase in the matrix to prevent coating failures resulting from coating-matrix interactions.
