PROCESS FOR ELECTRODEPOSITION OF COMPOSITE ZN-FE-TIOCOATINGS

摘要

The invention relates to a process for electrodeposition of composite Zn-Fe-TiOcoatings having higher corrosion resistance as compared to the zinc and zinc alloys coatings, the process being employed in coating certain subassemblies in the machine building industry. According to the invention, the process consists in depositing composite coatings of the composition Zn-(0.6...1%)Fe-(0.5...2%)TiOwhich are obtained of a non-cyanide alkaline electrolyte with addition of polysulphonic copolymer of dimethylamine with sulphurous anhydride and addition of hydrocarboxylic or polyhydrocarboxylic acid, at a working temperature ranging between 18...30°C and a current density of 0.5...6 A/dm, preferably 1...3 A/dm.