METHOD FOR PLASMA-ELECTROCHEMICAL FORMATION OF NANOSTRUCTURED CHROME SMOOTH COATING Russian patent published in 2022 - IPC C25D3/04 B82B3/00 

FIELD: electroplating.

SUBSTANCE: invention relates to the field of electroplating, in particular, to obtain a nanostructured chromium smooth coating, and can be used in mechanical engineering, instrument making and other fields of technology. The method consists in the fact that at the first stage, chromium is galvanically deposited with simultaneous burning of single microdischarges on the coating surface, for which the cathode, which is a chromium-plated product, is placed in an electrolytic bath with chromium plating electrolyte in a stationary state, then in a bath with an electrolyte solution parallel to the cathode the anode is placed and the treatment is carried out at a current density of 100–200 A/dm² and a voltage of 60–80 V to form a chromium layer of the required thickness on the cathode surface, at the same time, the same depth of immersion of the anode and cathode into the electrolyte is maintained, at the second stage, plasma etching is performed, for which the polarities of the anode and cathode are changed and the chrome-plated product becomes the anode, a capacitive induction filter is included in the electrical circuit, the voltage is increased to 350-400 V, in as a result, a gas discharge burns in a vapor-air shell covering the entire surface of the product, while the capacitive induction filter provides an adjustable smoothed voltage shape in the form of a constant, not reduced to zero, which makes it possible to uniformly influence the plasma on the chrome-plated surface of the product.

EFFECT: obtaining a nanostructured smooth chromium coating.

1 cl, 2 ex, 2 dwg