A finite-size model of reaction-diffusion type was proposed in order to explain the size effects of dislocation patterning in fatigued metals. It was demonstrated that the formation of certain patterns could be understood in terms of a competition between the intrinsic length scales of the Walgraef-Aifantis model and the linear size of the system. The latter could be taken to be equal to the grain size. Computer simulations demonstrated that, depending upon the grain size, it was possible to form a ladder structure of persistent slip bands (grain size of 13), or dislocation grids overlying grain boundaries (grain size of 1). Dislocation patterning could be prohibited when the grain size approached 0.1, and the system returned to the thermodynamic branch of solutions.

M.V.Glazov, C.Laird: Acta Metallurgica et Materialia, 1995, 43[7], 2849-57