Thie report was prepared as an accounl of Government aponwred u·ork. Nclther the United States, nor the Commission. nor any person acung on behalf of Be Commiselon:A. Makes any warranly or representation. expressed or implied. wil respect to ae accuracy. completeness. or usefulness of the informnuon contained tn t.hie report. or that the use of ony informalion, apparatus. method, or pricess disclosed in thls rcport rnay not 1./..ge In each case, formulations are developed along both one-and threedimensional diffusion models. These alternative results are compared with experiments, particularly annealing in copper irradiated by.electrons at low temperature. The results support the conclusion that the defect which migrates in Stage I diffuses in three dimensions.

The contribution of dragging of point defects attached to dislocation lines, to dislocation damping, to elastic modulus, and to logarithmic decrement, is developed. It is shown that the dragging leads to an initial increase in decrement in a suitable frequency range, determined by other related parameters: dislocation loop length, line tension, and damping constants.The theory predicts a dependence on frequency of v, in contrast to the Koehler-Granato-Lucke (KGL) frequency dependence of cu, explaining the failure of previous experiments to confirm the KGL theory. In a similar manner, the generally accepted dependences on point-defect density are shown to be incorrect at lower frequencies, below a few kHz in copper. For example, it is shown that the dislocation decrement should be proportional to the two-thirds power of the modulus defect, rather than proportional to the square of the modulus defect as previously expected, at large point-defect densities on dislocation lines.

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