“A copper and copper alloy surface chemical passivation method consists of the following steps of: caustic, acid, acid bright (polished), a passivation film forming process, a dilute chromic acid treatment, drying.”
The present invention belongs to the field of chemical conversion treatment of a metal material, suitable for chemically passivating the surface treatment of copper, copper-zinc and copper-zinc alloy of multi-component. Copper and brass easily rust in the atmosphere, it has long been widely used for the surface treatment process chromated surface to improve corrosion resistance of copper and brass.
Although the appearance of the product after the treatment process a golden yellow, and has good corrosion resistance.
Copper and copper alloys passivated continuous cleaning methods, including brushing degreasing, cold water, pickling, cold brushing, water washing, drying and passivation process, characterized in that the passivation process using benzo passivating liquid aqueous triazole or benzo triazole derivative, and a copper ion complexing agent is added in the above-described passivation solution.
Copper and copper alloys have high corrosion resistance of metal, but electrochemical corrosion prone to oxidation in a high temperature-humidity environment and cause discoloration, affect the quality and appearance of copper and copper alloys, in order to prevent the occurrence of discoloration, usually benzo an aqueous solution of triazole and its derivatives or anti-tarnish passivation of copper and copper alloy with an organic solution, impregnation treatment or spraying manner.