Recovery of Defects from 78° to 300°K in Cadmium Elongated at 78°K

Abstract

The motion of defects in polycrystalline cadmium (99.99%) deformed at 78°K has been studied from 78° to 300°K using electrical resistivity measured at the deformation temperature as an index of the defect concentration. There appear to be three stages of recovery, the first two are centered at 98° and 138°K with activation energies of 0.21 and 0.35 eV, respectively. The latter recovery state, which is attributed to the motion of vacancies, shows a similarity in several respects to recovery found in cold‐worked copper. A mechanism for the former recovery stage cannot be given; however, there is agreement in the number of jumps the defect makes before annihilation with the number in a recovery stage found in cold‐worked copper. A more complicated recovery stage occurs from 228° to 258°K with an energy increasing from 0.70 to 0.89 eV. Above this last stage, the resistance rises because of the anisotropy of the resistivity and a changed orientation of the recrystallized cadmium.