Improvement of Tribological Properties of the Piston Alloy AK12M2MgN by Ceramic Coating Modified by Graphine-Like Carbon

Based on our scientific and methodological principles of creating electrolyte suspensions, which include insoluble, solid nanoparticles of a different nature, the graphene-like carbon (GC) modification of ceramic coatings (CC) formed by microarc oxidation (MAO) on silumin containing up to 13 wt.% Si was carried out. It is established that the GC, introduced into basic silicate-alkaline electrolytes with a concentration of 250–1000 mg/l, intensifies microplasma processes, which is directly confirmed by an increase in the thickness of the CC by 1,2–1,5 times. At the same time, the participation of the GC in the process of coating formation leads to an increase in the content of corundum 2–3 times and, as a consequence, to the microhardness growth up to 24 GPa instead of 16 GPa for unmodified CC. It is also shown that when the GC-nanoparticles are included in the coating composition, their significant influence on the tribotechnical characteristics is revealed: a decrease in the coefficient of friction at loads of 20–50 GPa 1,3–2 times, wear rate 1,3–2,3 times.