About the Role of Graphene-like Carbon in the Formation of Coatings by the Method of Microarc Oxidation

Abstract

Based on the provisions of the discharge percolation theory, an interpretation is given for the mechanism of the effect of carbon nanoparticles introduced into the electrolyte on the microarc oxidation process. The effect of graphene-like carbon particles (GC) on the main characteristics of the formed coating is studied using the D16 alloy as an example. It is established that GC introduced in silicate-alkaline electrolytes at a concentration of 250–1000 mg/l intensifies microplasma processes, which is directly evidenced by an increase in the coating thickness by 1.3–2.2 times. At the same time, the participation of graphene particles in the process of coating formation leads to an increase in the content of corundum in it and, as a result, to an increase in microhardness up to 25 GPa relative to 15 GPa for unmodified coatings.

Keywords

• microarc oxidation
• modification
• aluminum alloys
• graphene
• shungite
• phase composition
• microhardness