The stress at the beginning of stage-III of the strain-hardening curve was determined as a function of temperature and strain rate in single crystals. It was shown that the results could be described by two theories of steady-state creep. These were based upon the diffusion-controlled motion of jogged screw dislocations and upon the diffusion-controlled climb of edge dislocations. At high temperatures, the data could be explained equally well by both theories. At low temperatures, the agreement was better in the case of the former theory. Using this model, the activation energy for self diffusion was deduced to be 3.6eV.

H.Siethoff, W.Schroter: Philosophical Magazine, 1978, 37[6], 711-8