Nanostructured Al-O-Me Coatings Obtained by the Microtribological Method

Abstract

Microscopic mass transfer by wear was used to obtain Al coatings on Al, Cu and glass substrates at action of a rotating wire brush. The process was performed in the conditions of severe shear deformations and intensive oxidation of small transferred metal particles at room temperature. Structure, composition and micromechanical properties were investigated using XRD, SIMS, electron, optical and atomic force microscopy and precision microindentation techniques. Coatings are characterized by the thermally stable nonhomogeneous nanostructure (50-200 nm) and good adhesion to the substrates. Microhardness values were by a factor of 3-10 higher than the source metals. Coatings show quasiplastic fracture behaviour. Such properties are determined by the formation of Al based nanostructured composite stabilized by the presence of oxidized interlayers, which act as barriers for the grain growth in wide annealing temperature regions.