On the protection of UO 2, U and UC by metal films against fission induced losses of uranium

Abstract

Pellets of UO 2, U and UC, either bare or covered with thin films of nickel or gold were irradiated at thermal neutron doses of 0.2 × 10 19 to 0.9 × 10 19 n/cm 2, to determine by the collector method the ejection rates of uranium from their surfaces. The ejection rates found for bare emitters were comparable to those observed by other authors. The losses of uranium from the Ni-covered emitters were lower by a factor of 2 to 4, those of the Au-covered emitters were widely scattered. The ejected matter was deposited on carbon films in the form of spots (islands). The spot density and the size of the spots varied, depending on the nature of the emitting material and the distance of the carbon films from the emitter.