The effects of high-energy Gamma radiation on dielectric solids

The kinds and magnitudes of radiations present in the various locations near nuclear reactors are discussed as well as the mechanisms of interaction of radiation with matter, namely, group fragmentation, molecular scission, and polymerization. Techniques and locations for obtaining high dose rates are presented. Results of 60-cycle short-time voltage breakdown tests on polyethylene, cellulose acetate, and polyvinyl chloride films along with Formex*-varnished wire are given as a function of integrated dose up to 108 roentgens. Extensive electrical tests on a mica-glass-silicone-resin insulation simulating that used in the electromagnetic pump for the submarine intermediate reactor are described. Measurements of mechanical property changes of irradiated resins by means of a newly developed penetrometer are presented.