METHOD OF PRODUCING PROTECTIVE COMPOSITE COATING ON STEEL PART Russian patent published in 2020 - IPC C23C22/07 C23C22/18 C23C22/82 C23C24/00 C23C28/00 

FIELD: technological processes.

SUBSTANCE: invention relates to chemical surface treatment. Method involves successive application on surface of part of two layers of coating, each of which is formed by depositing aluminum powder in solution of inorganic binder by dyeing with subsequent thermo hardening of applied coating layer and machining of part with applied coating layer. Suspension of aluminum powder is used in solution of inorganic binder, prepared from following components, wt%: aluminum hydroxide 1.2-1.6, solution of 85% orthophosphoric acid 4.7-5.5, magnesium oxide 0.12-0.16, potassium permanganate 0.25-0.33, aluminum powder 45.0-55.0, sodium silicate or potassium silicate 0.25-0.37, distilled water - balance. Inorganic binder is distilled water to specific density of 1.20-1.30 g/cm³. Thermosetting is followed by additional treatment with corundum powder at pressure of 2 to 3 bar.

EFFECT: high protective capacity of the obtained coating from corrosion with simultaneous reduction of the thickness of the coating, hardening temperature of up to 200°C, simple process of applying protective coating, as well as avoiding use of substances of 1st class of hazard.

1 cl, 2 dwg, 2 tbl