STUDY OF STRUCTURAL CHANGES PRODUCED BY NEUTRON IRRADIATION

Measurements were made of the electrical resistance of neutron- irradiated U-9 wt.% Mo alloy, and x-raydiffraction and microscopic analyses were carried out to determine the structural changes in the specimen. Preliminary annealing yielded specimens with eutectic structure alpha + gamma ' of various grain sizes. The rate of diffusion under irradiation of the annealed alloy is inversely proportional to the grain area. In homogeneous specimens ( gamma phase) radiation induced quick alteration of properties and structure of the alloy. Observations of irradiation effects indicated a certain disorder during gamma phase transition into cubic lattice. The results of the investigation are in good agreement with theory; however, the magnitudes of the thermal peak and energy were obtained as 2.5 a 10/sup -7/ cm/sup 3/ and ~2 Mev, respectively, which are smaller than the magnitudes derived previously. (tr-auth)