Influence of the amount of strain at 78°K on the recovery process in Al 99.995%

Publisher Website
Google Scholar
Abstract
Recovery processes in 99.995% purity Al following deformation by torsion at 78°K have been investigated by resistometric means after several amounts of strain. The results show that the annealing of point defects is scarcely influenced by the degree of deformation and takes place in two recovery stages. The first is centred at about 80°K and is attributed to the annealing of interstitials to dislocations. The second, in the range of 160 to 260°K, has an activation energy of 0.57 ± 0.01 ev and is attributed to the annealing of vacancies to dislocations. The mechanism for dislocation removal at and just above room temperature is strongly dependent on the amount of strain. Polygonization is usually observed to take place at room temperature in 99.995% purity Al, and a recrystallization process characteristic of zone-refined Al can also occur after very large strains.