METHOD OF MAKING GALVANIC FRACTAL COATS OF CHROMIUM Russian patent published in 2005 - IPC

FIELD: application of coats by electrolytic methods; making galvanic fractal coats of different configuration.

SUBSTANCE: proposed method includes preliminary treatment of surface of part before application of coat, electrochemical precipitation of chromium on part used as cathode; treatment of part consists in forming roughness within 10-200 mcm. Precipitation is performed from electrolyte containing CrO₃ and H₂SO₄ at the following composition of components, g/l: CrO₃, 250 and H₂SO₄, 2.5. Precipitation is continued for 18-20 h at rate of chromium plating of 13 mcm/h and electrolyte temperature of 45-55 C and DC density of 0.3 A/sq cm. Proposed method ensures making of mechanically stable coats whose hardness exceeds hardness of galvanic polycrystal chromium coats by 1.6 times.

EFFECT: enhanced wear resistance and improved decorative properties of coats.

3 cl, 2 dwg, 1 ex