CYCLIC DEFORMATION OF NEUTRON IRRADIATED COPPER

Copper single crystals irradiated to a neutron dose of 1·1 × 1018 n/cm2 (> 1 MeV) have been cycled between constant plastic elongation limits at room temperature. The general cyclic deformation characteristics have been ascertained and some qualitative ideas on the mechanisms of deformation developed. Transmission electron microscopy reveals that channels completely free of irradiation-produced defects are created during the cyclic strain programme. The width and spacing of the channels have been shown to be a function of the number of cycles. An electron microscope shadowgraph technique has also been used to study the exact shape and distribution of surface slip steps and the results are compared to the channel observations. © 1968 Taylor & Francis Group, LLC.