CHROME-PLATED PART (VERSIONS), AND ITS MANUFACTURING METHOD Russian patent published in 2013 - IPC C25D5/14 C23C28/00 

FIELD: metallurgy.

SUBSTANCE: part includes a substrate, a lustre nickel coating layer above the substrate, a nickel coating layer with precious potential on the lustre nickel coating layer; with that, difference of electrical potentials between the above layers is within 40 mV to 150 mV, and a trivalent chrome coating layer formed on the nickel coating layer with precious potential and having at least one of the structure with micropores and structure with microcracks. Trivalent chrome coating layer has 10000/cm² or smaller pores or includes 4.0 to 20 atm % of carbon and 7 to 16 atm % of oxygen, or has been obtained by means of the main chromic sulphate as metal source and in addition it contains 0.5 atm % of iron or more, or contains at least one of 0.5 atm % of iron or more and 4.0 atm % of carbon or more, or contains at least one of 1 atm % to 20 atm % of iron and 10 atm % to 20 atm % of carbon, or is amorphous. The method involves formation of the lustre nickel coating layer above the substrate, formation of layer of nickel coating with precious potential on the lustre nickel coating layer; with that, difference of electric potentials between layers is 40 to 150 mV, and electric deposition of the trivalent chrome coating layer on the layer of nickel coating with precious potential. Amount of electric potential regulator added to the first electrolytic bath for formation of the layer of nickel coating with precious potential is regulated so that it can be higher than the amount added to the second electrolytic bath for formation of a lustre nickel coating layer.

EFFECT: improvement of part characteristics.

10 cl, 7 dwg