Restructuring of the Phase Boundary during the Implementation of High-Energy Chemical and Electrochemical Reactions and the Influence of Restructuring on Characteristics of Coatings

Abstract

It is shown that high-energy impact on the phase boundary by the method of pulsed microplasma oxidation with a trapezoidal pulse shape leads to localization of high-density energy in the near-electrode layer, bifurcation of the electrolyte flow, restructuring of the phase boundary, and fragmentation of the boundary hydrodynamic layer. The processes of phase-boundary restructuring and boundary-layer fragmentation, which affect the structure of porous oxide coatings, were determined and modeled. It has been shown that fragmentation leads to the appearance of ring structures, which are then reconstructed into more complex and larger structures, inside which small-diameter pores remain, with a porous oxide coating being formed. Differences have been identified elemental composition in the center and at the boundary of the boundary-layer fragment, caused by different rates of electrochemical reactions in different parts of the fragment.