Abstract
The effect of plastic deformation on the formation of point defects and defect clusters by electron irradiation has been studied in Ll2 ordered Ni3Ge and Ni3Al by high voltage electron microscopy. It is found that defects are formed preferentially along the Burgers vector directions as linear lines and grow into linear chains of clusters by electron irradiation. This phenomenon is explained by preferential generation of the defects along the antiphase boundary (APB) tubes, in specimens deformed both below and above the peak temperature T P. Based on three-dimensional analyses of the defect distribution, the formation mechanism of the APB tubes is discussed with particular reference to superdislocation motion and the strengthening of the Ll2 ordered compounds of Ni3Ge and Ni3Al.