Gamma uranium-molybdenum alloys behavior under hydrogen atmosphere

Abstract

Due to its best irradiation and metallurgical processing performance, gamma uranium-molybdenum alloys are the best candidates for the use as high density / low enriched research reactor fuels. To the fabrication of U-Mo / Al dispersion fuel plates, gamma uranium-molybdenum powder obtention is one of the main processing steps, and to reach this goal, the route considered is hydrationdehydration (H-DH). In this work, some of the experimental results related to the hydration-dehydration of gamma uranium-molybdenum alloys are presented. Additions of 5, 6 and 7% wt% Mo were prepared by arc and induction melting, its as cast structures characterized by optical microscopy, MEV and X-ray diffraction, and related to the results obtained after being thermally treated under hydrogen atmosphere, for several conditions of time and temperature. First examinations showed that the gamma U-Mo alloy hydrogen susceptibility and the yielding in the powder production increases with the decrease in the Mo addition. Since the traditional pre-treatment before the hydration was not considered here, some important conclusions concerning the steps to produce the powder by the HDH process could be taken.