<i>'In situ'</i>straining in the HVEM of neutron-irradiated copper crystals

Abstract

Abstract High-energy-neutron-irradiated copper single crystals strained 'in situ' in the high voltage electron microscope have been observed to yield in relatively few strongly developed slip bands. The deformation in the slip hands is caused by glide of inclined dislocations close to screw orientation belonging to the primary slip system. Radiation-induced point-defect clusters are swept up by the dislocations forming superjogs. Some of the jogs act as pinning points for the gliding dislocations, which bow out under the applied stress to form perfect, as well as faulted, dipoles, which are finally pinched off. The effective stress measured from the radius of curvature of the bowed-out, dislocations is in agreement with resolved flow stress measurements from irradiated bull; crystals.