The fast diffusional growth of an interphase layer during the initial stages of reactive diffusion was considered. The phenomenon of rapid growth was attributed to grain-boundary diffusivity and to accelerated bulk diffusion due to vacancy supersaturation. In the latter case, vacancy-source movement and the spatial distribution of non-equilibrium vacancies was involved. It was shown that, if bulk diffusion predominated due to vacancy supersaturation, the process was enhanced by grain-boundary diffusion.

On the Problem of High-Rate Reactive Diffusion. L.Levin, A.Katsman: Materials Chemistry and Physics, 1998, 53[1], 73-6