Continuous Observation of Dynamic Behaviors of Dislocations in Aluminum

Foil specimens of about 3µ in thickness were directly stretched inside a 500 kV electron microscope, and the dynamic behaviors of dislocations were continuously observed. When the specimens are deformed, frequency of cross slip is increased with increasing amount of deformation, and a number of small prismatic dislocation loops are formed. Mechanical and thermal stability of these loops are related to their size; i.e. , small ones are fairly...