Preparation method of nickel-cobalt plated layer on inner wall of ring-shaped copper piece

Abstract

The invention discloses a preparation method of a nickel-cobalt plated layer on the inner wall of a ring-shaped copper piece. The nickel-cobalt plated layer is prepared by the adoption of a tank-freeelectro-deposition technology. According to the tank-free electro-deposition technology, a nickel plate used as the anode is dipped in an alkaline deposition solution and rotates on the inner wall ofthe ring-shaped copper piece as the cathode, and then the nickel-cobalt plated layer is deposited on the inner wall of the ring-shaped copper piece. According to the preparation method of the nickel-cobalt plated layer on the inner wall of the ring-shaped copper piece, the tank-free electro-deposition technology is adopted, through repeated friction between the anode and the cathode, the defects,such as pinholes, pocking points and nodules, existing in the conventional electro-deposition process can be effectively overcome, the obtained nickel-cobalt plated layer is compact in structure, smooth in surface and good in quality, and the service life of the ring-shaped copper piece is greatly prolonged. The thickness of the nickel-cobalt plated layer obtained by the adoption of the preparation method can reach 800-1200 microns, and the hardness of the obtained nickel-cobalt plated layer can reach 450-550 HV. Besides, the obtained nickel-cobalt plated layer has good adhesion strength witha substrate, is good in wear resistance and can meet the use requirements in severe environments.

Description

technical field [0001] The invention belongs to the technical field of electrodeposition, and in particular relates to a method for preparing a nickel-cobalt coating on the inner wall of a copper ring. Background technique [0002] At present, the commonly used inner coatings of copper rings are mainly pure nickel coatings or nickel-iron coatings. The pure nickel coating has low hardness, cannot resist the wear of the billet, and has a short service life. The nickel-iron coating has poor thermal alternating resistance and electrochemical corrosion resistance, and the plating solution is not easy to control. If the control is not good, the yield rate will be low, and the actual service life will fluctuate greatly. [0003] Nickel-cobalt alloy is a nickel-based alloy with excellent performance. Compared with pure nickel coating and nickel-iron coating, nickel-cobalt coating has two advantages besides similar physical and chemical properties: (1) higher hardness, especially I...

AI Technical Summary

Problems solved by technology

[0004] However, due to factors such as hydrogen evolution in aqueous solution, impurity adsorption, and tip discharge, the use of conventional electroplating methods to prepare nickel-cobalt coatings on the inner wall of copper rings has the following disadvantages: (1) The crystal grains are usually relatively coarse, and prone to pinholes, numbness, etc. (2) It is difficult to prepare nickel-cobalt coatings with high hardness and thickness

Images