The reorientation and termination of dislocation dipoles

Abstract
The self-stresses which dekink a bent dipole and which reorient a dipole to the edge configuration have been calculated. Using these equations it is found that dipoles cannot terminate by self-kinking within the dipole to form screw segments which annihilate. Washburn's proposed mechanism for dipole termination has been analysed theoretically and has explained many features of observed elongated dislocation loops. It is proposed that the lattice friction of a metal can be determined experimentally from the observed maximum misorientation of smooth dislocation dipoles. Using graphs of Low and Turkalo the lattice friction of silicon iron at room temperature is estimated to be 7 × 10−4 μ or 4 × 108 dynes/cm2.