MODIFICATION OF METAL SURFACE BY ELECTROPLATING AND VACUUM ARC DEPOSITION

摘要

The decorative finishing by metal plating allows one to improve the aesthetic appearance and corrosion resistance. The new compositions of the additives for copper and nickel electroplating were developed allowing to deposit coatings with given brilliance, roughness and surface patterns. These characteristics of a deposited coating vary depending on the composition of an additive and the electrolysis mode. For example, the change of velocity and flow direction of agitated electrolyte during electrolysis considerably influences a degree of the electrodeposit roughness. The new technique permits to deposit the novel protective and decorative copper and nickel coatings with the "Velvet", "Sateen" and "Velour" surface patterns. An electrodeposition of thin Ni and Cr layers or vacuum arc deposition of TiN or TiO_2 on the "Velvet", "Sateen" and "Velour" patterned coatings strengthens the decorative effect and essentially increases the corrosion resistance of coated parts.