A mesoscopic model of dissolution/disintegration of nanocrystalline metals via vacancy diffusion along grain boundaries

We propose a model describing the growth of a two-dimensional subsurface pore induced by vacancy supersaturation on the surface of a polycrystal. We demonstrate that the pore develops narrow slits propagating along the grain boundaries which may lead to disintegration of nanocrystalline metal by grain detachment. Analytic models describing initial and final (on the verge of grain detachment) stages of pore growth are proposed. The models’ predictions are in good agreement with the numerical simulation results.