LOW TEMPERATURE RECOVERY OF DEFORMED ZIRCONIUM

Abstract

The low-temperature recovery of the electrical resistivity increment Δρ0 produced by deformation of polycrystalline Zr at 4.2 °K was investigated. Particular attention was given to the large recovery stage occurring between 30° and 40 °K, which amounted to 30% of Δρ0 for Zr containing ~0.070 at. % oxygen, but only 6% of Δρ0 for Zr containing ~0.015 at. % oxygen. By means of isochronal and isothermal anneals, this recovery stage was shown to be due to several first-order annealing processes (with activation energies between 0.105 and 0.125 eV), which were attributed to defect-oxygen atom interactions. Additional recovery peaks were observed at 190 °K and 310 °K only for the lower purity Zr, whose recovery to 360 °K was approximately 80%.