Abstract
Dislocation loops with Burgers vector a〈100〉 are formed in Cu-Ni alloys during 1 MeV electron irradiation in a high-voltage electron microscope at 350°-400°C. The dislocation loops are of interstitial type and pure edge in character with 〈110〉 line vectors. Some of the loops are seen to dissociate into loops with Burgers vector a/2〈110〉.