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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Radiant signs contract on microreactors for the military
California-based microreactor developer Radiant Industries has announced the signing of what it calls “the first-ever agreement” to deliver a mass-manufactured nuclear microreactor to a U.S. military base. The contract was signed with the Department of Defense’s Defense Innovation Unit (DIU) and the U.S. Air Force as part of the Advanced Nuclear Power for Installations (ANPI) program.
G. W. Keilholtz, R. E. Moore
Nuclear Technology | Volume 3 | Number 11 | November 1967 | Pages 686-691
Technical Paper and Note | doi.org/10.13182/NT67-A27904
Articles are hosted by Taylor and Francis Online.
The effects of neutron irradiation on poly crystalline α-alumina were investigated. The specimens were translucent solid cylinders of 99.8% of theoretical density with an average grain size of 25 μm. Fast (> 1 MeV) neutron exposures ranged from 0.6 to 5.2 × 1021 n/cm2 where the thermal-to-fast flux ratio varied from 1.6 to 1.1. Temperatures of the specimens were calculated to range from 300 to 600°C. Grain-boundary separation was observed when the neutron dose (> 1 MeV) was approximately 2.3 × 1021 n/cm2, and it became progressively worse with increasing neutron dose. Extensive fracture was observed in specimens exposed to doses above 3 × 1021 n/cm2 (> 1 MeV), but there was virtually no fracturing of samples exposed to doses less than 2 × 1021 n/cm2. Volume of the specimens increased as the neutron dose increased, but the volume as calculated from the lattice parameters, which increased in specimens exposed to a neutron dose of 0.7 × 1021 n/cm2, decreased slightly with additional radiation. Above 0.7 × 1021 n/cm2, the a parameter remained constant while the c parameter decreased. It is suggested that grain-boundary separation, which causes the fracturing of the specimens, is produced by an anisotropic expansion of the crystals produced by defect agglomerates which are too large to affect the lattice parameter measurements.