The role of radioactive decay in irradiation damage in metals

Abstract

The effects which may accompany radioactive decay in irradiated metals can be described in terms of five mechanisms. Two are responsible for the production of defects, and two can annihilate existing defects. The fifth mechanism is the formation of transmutations. The relative importance of each mechanism is dependent upon the nuclear properties and damage state of the metal. The experimental observation of the effects of some of these mechanisms is made by means of resistivity change measurements in thermal neutron-irradiated Cu, W, Re, and Au. The observation of those effects which producecompensatingchanges is accomplished through the use of postirradiation annealing procedures and control of defect concentration.

An ephemeral Frenkel pair in iridium

“…can only be attributed to a recombination of Frenkel pairs, this recombination being induced by one of the nuclear reactions. Such recombinations have been previously observed by Coltman et al [ 10].…”

“…defects through recoil phenomena has been observed in quite a few metals [10]. At the end of the irradiation, we are thus left with a concentration c'j 4 = 0.55 c'4 of (I -i)4 pairs, where c'4 is the concentration of 194Ir atoms U = (I) or (II)).…”