METHOD OF FORMING PROTECTIVE OXIDE AND CERAMIC COATING ON THE SURFACE OF VENTILATION METALS AND ALLOYS Russian patent published in 2019 - IPC C25D11/00 

FIELD: electroplating.

SUBSTANCE: invention relates to electroplating and can be used in mechanical engineering, medicine, automotive, aerospace, radio-electronic industry in both single and serial production. Method of plasma electrolytic oxidation (PEO) involves immersing product as electrode together with counter electrode in bath filled with alkaline aqueous electrolyte, and applying bipolar voltage pulses to electrodes using pulsed power source, while bipolar rectangular voltage pulses are applied to electrodes, moreover, anode pulse is followed by current-free pause and then cathode pulse, while the ratio of anode pulse duration and current-free pause (Ta / To) is chosen in range from 1:5 to 1:6, and duration of anodic pulse is 3–30 mcs and total period duration (T = Ta + To + Tk) is 30–300 mcs, between amplitude values and durations of anodic and cathodic voltage pulses withstand ratio U_a * T_a = U_to * T_to, PEO is carried out when amplitude values of voltage pulses of anodic 600–1200 V and cathode 150–400 V, depending on nature of oxidized material.

EFFECT: obtaining molten uniformly uniform in thickness oxide-ceramic coatings with unique physicomechanical properties: high hardness, elastic modulus, adhesive and cohesive strength and density.

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