NATURE OF HIGH-ENERGY NEUTRON DAMAGE IN COPPER AND GOLD

Transmission electron microscope studies have been made on the defect clusters in high-purity copper and gold single crystals produced by d-Be, D-T and fission neutron irradiations at ambient temperatures. The vacancy or interstitial nature of the defect clusters and Burgers vectors and habit planes were determined from the direction of the black-white contrast in dynamical images of the clusters and from depth information obtained from stereo measurements. Studies were also made using the weak-beam technique combined with stereo measurements to obtain spatial distribution information on vacancy clusters. It is shown that the nature of high-energy neutron damage is quite similar to fission neutron damage for copper. Significant differences between high energy and fission neutron damage particularly in the amount of retained damage, exist in the case of gold. © 1979.