It was noted that, in the Koehler dislocation multiplication process, segments of screw dislocation glided off the primary glide-plane, onto secondary planes, and then back onto a primary plane which was parallel to the first one. This generated trailing dipoles, for small excursions between the two primary planes, or pinning-points of Frank-Read mills in the case of large excursions. The mechanism that caused the lines to cross-glide, and the distribution of dipole heights that resulted, were considered here. It was proposed that self-excited oscillations of moving dislocation lines, caused by thermally induced shear-strain fluctuations, caused the cross-gliding. The properties of this process were similar to a two-dimensional random walk, and this determined the dipole-height distribution. The Koehler process predominated for dislocation multiplication in structural materials; especially at high strain-rates. The resultant dipole height distribution was an important factor in determining various properties of the cold-worked state.

Mechanism of the Koehler Dislocation Multiplication Process. J.J.Gilman: Philosophical Magazine A, 1997, 76[2], 329-36