Mechanochemical Oxidation of a Surface of Metal Alloys under the Impact of Severe Plastic Deformation

Abstract

The purpose of this review consists in the consideration of mechanochemical processes, particularly, mechanochemical oxidation of the surface of different materials under the severe plastic-deformation exposure. The nature of mechanochemical reactions with the formation of the oxide film at the mechanical exposure, particularly during the processes of friction and wear of materials, is considered. As shown, the increase of the mechanochemical activity of surface layers of metal alloys during the different mechanical treatments is associated, first of all, with the accumulation of structural defects (point ones, dislocations), the formation of juvenile surfaces, amorphous phases, etc. The effect of mechanochemical oxygen interaction with the surface of titanium and aluminium alloys under the exposure of ultrasonic impact treatment in the air is revealed. The mechanism of mechanochemical synthesis of strong oxide layer is suggested, and the kinetics of the surface oxidation under such type of severe plastic deformation is studied.

Keywords