Structure and Properties of Black Ceramic MAO Coatings on Aluminum Alloys

The existing processes for obtaining black wear-resistant coatings include chemical methods, anodic oxidation followed by painting in aniline dyes, electrochemical deposition, vacuum plasma treatment, microarc (MAO). Of great interest the formation of light-absorbing is MAO method, which characterized as a reliable and environmentally friendly process, provides hard ceramic-like oxide layer with high corrosion resistance аnd good adhesion to substrate. Therefore, development methods high-quality both optical mechanical characteristics currently an urgent task. paper presents results study structure properties ceramic on aluminum alloy AMg2 obtained using silicate-alkaline silicate-phosphate electrolytes containing potassium ferrocyanide sodium tungstate coloring components. Sodium tungsten acid concentration 0.5 2.0 g/l were added additional components that ensured coatings. It has been established most saturated electrolyte are formed addition 1.5–2.0 tungstate, 1.5 ferrocyanide. use makes it possible form lower microroughness height (Ra 0.97–1.11 µm) compared up 4.20 µm). maximum wear resulting (wear rate (0.38–0.59) × 10 –4 mm 3 /(m×N)) achieved treatment studied duration min. In this case, thickness 21–31 µm. A further increase processing does not have significant effect rate.