IRRADIATION SWELLING, PHASE REVERSION, AND INTERGRANULAR CRACKING OF U - 10 wt % Mo FUEL ALLOY

摘要

A fuel development program has been conducted, to investigate the behavior of U - 10 wt％ Mo alloy at the fission rates and temperatures anticipated in Core I of the Haliam Nuclear Power Facility. Unrestrained samples, 0.5 in. in diameter by 2.0 in. long, were irradiated in the Materials Testing Reactor for periods up to three years, to achieve substantial burnup levels at the relatively low Core I burnup rates. The specimens were irradiated in the fission rate range from 2.5 to 8.0x1012 fissions/cc- sec, at average central temperatures from 750 to 1085°F. Initially, the fuel specimen structures were as-cast (inhomogeneous 7), partially transformed (а + γ’ + γ), or homogenized (γ).