The effect of defects, introduced by quenching or plastic deformation, upon the acceleration of surface segregation kinetics in the Ni-S system was studied. An estimation was made of the diffusion coefficient of S in as-quenched single crystals of Ni. In cold-worked structures, the annihilation of vacancies produced very rapid segregation of S atoms to the dislocation network at the beginning of annealing. The diffusion acceleration became really significant when the pipes, in sub-grain boundaries that resulted from deformation, rearranged to form a percolated network. The results demonstrated that the micro-structural evolution of diffusion short-circuits should be taken into account when analyzing complex diffusion kinetics.

Effects of Metastable Diffusion Short-Circuits on Surface Segregation. R.Le Gall, G.Saindrenan: Interface Science, 2003, 11[1], 59-66