A model was proposed for the description of the effect of a single lattice dislocation, that was trapped by a grain boundary, upon the diffusion properties of the latter. The model was based upon the fact that the grain-boundary free volume changed within the core of a spreading dislocation. Expressions were derived which permitted the estimation of the extent of the effect of the dislocation upon grain-boundary diffusion, as well as the characteristic time of this effect. Expressions were also derived for the grain-boundary diffusivity within the core of the spreading dislocation and for the effective diffusion coefficient in a grain boundary with a trapped lattice dislocation.

V.N.Chuvildeev: Physics of Metals and Metallography, 1996, 81[6], 583-8