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Fertile material
A material, which is not itself fissile (fissionable by thermal neutrons), that can be converted into a fissile material by irradiation in a reactor. There are two basic fertile materials: uranium-238 and thorium-232. When these fertile materials capture neutrons, they are converted into fissile plutonium-239 and uranium-233, respectively.
Page Last Reviewed/Updated Thursday, August 27, 2026
Page Last Reviewed/Updated Thursday, August 27, 2026