It was recalled that, in many experiments, curved penetration profiles were observed for grain boundary diffusion which was performed in the B kinetics regime; in contrast to the shape which was expected from solutions of Fick’s second equation. In order to explain the curvature, the effects of grain-boundary structure, grain-boundary migration and grain-boundary segregation had been proposed in the literature. By using previous data on Cu–Ag and Cu–Ni, and new data on Cu–Fe and Cu–Zn systems, it was shown to be possible to separate all of the possible contributions. Knowing the true origin of the curvature, it became possible to deduce quantitative information which was difficult to obtain by using other techniques.

Effect of Grain Boundary Segregation and Migration on Diffusion Profiles - Analysis and Experiments. J.Bernardini, C.Girardeaux, A.Rolland, D.L.Beke: Interface Science, 2003, 11[1], 33-40