Nano-Transformations in the Surface Layer of Materials Under Combined Processing by Unbound Granules

Abstract

The article considers nano-transformations of the surface layer, occurring in combined dimensional finishing with an electric field applied by a tool in the form of unbound metal granules. The object of study are geometrically-complex parts, used in aviation, rocket and space engineering, as well as in oil-and-gas industry, namely, rotors and flow parts of turbopump unit casings, screw conveyers and impellers with sections of various curvature, providing limited access of the tool to the processing zone. It is shown that the combined process involving the fusion of two-component processing media, composed from current-carrying granules, and an electrically conductive liquid medium, supplied to the processing zone at high speed, helps to achieve the required quality of the surface layer. The action of the electric field from a high-voltage source makes it possible to achieve the required peening against the strikes of solid granules in the process of dimensional finishing. This gives the possibility to increase the service life and durability of critical units of aerospace and oil-and-gas equipment, and broaden the scope of using combined processing by unbound granules, as to comprise the components with sections, inaccessible for processing by a profiled electrode.