Flattening of a passivated solid surface due to capillarity

We considered flattening of a nearly plane solid surface covered with a thin, inert and fully elastic passivation layer. We demonstrated that instead of relaxing to a planar state the passivated surface retains some residual roughness. We determined the kinetics of surface flattening controlled by self-diffusion along the solid-passivation layer interface. The passivation layer slows down the flattening process, if compared with the behavior of unpassivated surface. This slowing down becomes more severe with increasing passivation layer thickness. (c) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.