Effects of Neutron Irradiation on Precipitation-Hardening Alloys

Abstract

The effects of neutron irradiation on age-hardening alloys are of great importance in determining the usefulness of these alloys in reactors and are, in addition, of fundamental interest in determining the basic mechanisms of radiation effects. Most of the work has been on alloys irradiated as supersaturated solid solutions, although some data are available for specimens irradiated in the aged condition. Irradiation can enhance solid state diffusion sufficiently to initiate precipitation or to allow growth of existing precipitates, which can lead to overaging. In addition, precipitate nuclei can be redissolved by neutron irradiation. Either overaging or re-solution will reduce the strength of the alloy and will affect physical properties as well. This paper describes the effects of irradiation on the mechanical, electrical, and magnetic properties of alloys in the groups listed below and relates the effects, where possible, to structural changes: copper-beryllium, nickel-beryllium, copper-iron, copper-cobalt, zirconium-columbium (niobium), certain nickel-base alloys, and precipitation-hardenable steels. Work in progress includes studies of aluminum-copper and nickel-titanium alloys.