METHOD OF APPLYING CHROMIUM COATING ON PRECISION PARTS FROM LOW-ALLOY STRUCTURAL STEELS Russian patent published in 2020 - IPC C23C16/16 C23C16/46 

FIELD: metallurgy.

SUBSTANCE: invention relates to production of metal coatings and can be used for application of coatings at hardening of precision parts from low-alloy steels road-building, rescue and tillage, agricultural, lumbering machines in conditions of repair enterprises. Method of chromium coating application on precision parts from low-alloy structural steels includes application of chromium coating adhesive layer on part surface, heated to temperature from 390 to 410 °C, at residual pressure for 5 to 10 min and subsequent application of main coating layer by feeding chromium hexacarbonyl vapour onto part surface cooled to temperature of 200 to 250 °C, with thermal decomposition of chromium hexacarbonyl vapour. Chromium coating adhesive layer on part surface is applied with thickness of 4 to 6 mcm by feeding chromium hexacarbonyl vapour at 35 to 45 °C at rate of 1 to 2 l/h at residual pressure of 10 to 20 Pa with thermal decomposition of chromium hexacarbonyl vapour. Main layer of the coating is deposited with thickness of 35 to 45 mcm by feeding chromium hexacarbonyl vapour at temperature of 55 to 65 °C on the surface of part for 40-60 min with thermal decomposition of chromium hexacarbonyl vapour.

EFFECT: higher wear resistance and longer service life of assembly unit.

1 cl, 1 tbl, 3 ex