A theoretical investigation was made of dislocation density fluctuations and instabilities in a system of uncompensated dislocations under conditions of single slip of dislocations that were generated by bulk and surface sources. Beginning with the equations of dislocation kinetics, dispersion relations were obtained for the Fourier components of dislocation density fluctuations. In a system of uncompensated dislocations, the Fourier components of the disturbances were shown to represent running waves that grew if they propagated along the direction of the movement of uncompensated dislocations. At high rates, instabilities of convective type could arise due to a rapid drift (entrainment) of dislocation-density fluctuations. The growth of dislocation density fluctuations was associated with the formation of a sub-structure of misoriented sub-grains.

Fluctuations and Instabilities in a System of Uncompensated Dislocations. S.K.Khannanov: Physics of Metals and Metallography, 1997, 84[3], 208-15