Surface treatment method of zinc-alloy high-hardness abrasion-resistant imitating electroplating hexavalent chromium

Abstract

The invention relates to a surface treatment method of zinc-alloy high-hardness abrasion-resistant imitating electroplating hexavalent chromium. The method is characterized by comprising the steps as follows: 1) surface treatment is performed on a to-be-treated zinc alloy workpiece; 2) the workpiece is placed into a hydrofluoric acid solution to be etched and activated; 3) the activated workpiece is washed clean with pure water and then placed into a silane oxide tank solution for silane conversion coating treatment, and the workpiece is washed with water after treatment; 4) the workpiece is placed into an electrophoresis tank for electrophoresis, and an electrophoresis coating is formed on the surface of the workpiece; 5) cleaning is performed; 6) pre-drying is performed; 7) ultraviolet curing is performed; 8) the workpiece is hung in a PVD (physical vapor deposition) furnace, and a layer of metal and ceramic composite film is formed; 9) finally, PVD is performed on the surface of the workpiece again, and a layer of transparent DLC (diamond like carbon) film is deposited. By the aid of the method, the problem of the low good product yield of an electroplated zinc alloy due to die-casting sand holes and nests and the like is solved, the quality is stable, and the good product yield is high; the method is environment-friendly, simple in process and low in energy consumption.

Description

technical field [0001] The invention relates to a surface treatment method, in particular to a surface treatment method for a zinc alloy with high hardness and wear resistance imitating electroplating hexavalent chromium. Background technique [0002] At present, the zinc alloy chrome-plated products on the market are electroplated with hexavalent chromium, using the traditional water electroplating process. The water electroplating process has the following disadvantages: (1) consumes a lot of water and energy, produces a large amount of waste water and waste residue, and the cost of waste water and waste residue treatment is high; (2) uses harmful chemical plating solution and additives; (3) discharges toxic waste gas; (4) The amount of metal consumed is large; (5) the hexavalent chromium used is harmful to the human body. Moreover, zinc alloy electroplating with hexavalent chromium often causes blistering of the coating, separation of the coating from the substrate, etc....

AI Technical Summary

Problems solved by technology

The water electroplating process has the following disadvantages: (1) consumes a lot of water and energy, produces a large amount of waste water and waste residue, and the cost of waste water and waste residue treatment is high; (2) uses harmful chemical plating solution and additives; (3) discharges toxic waste gas; (4) Consumption of a large amount of metal; (5) the use of hexavalent chromium is harmful to the human body

[0005] The Chinese invention patent application with the notification number CN102758176A discloses "A Method for Carrying out All-Dry Composite Coating on Metal Surfaces", which is mainly a surface treatment method for imitating electroplating of hexavalent chromium directly on polished metal substrates. It has high requirements on the polishing of metal substrates, and the polished surface is required to be as bright as a mirror. For the trachoma nests of die-cast zinc alloys, this method is powerless