What is the role of fastener surface plating treatment?

Update:28 Sep 2020

The surface electroplating treatment of high-strength s […]

The surface electroplating treatment of high-strength screw fasteners forms a process of covering the surface of the fasteners. After the surface treatment of the fasteners, they can present a more beautiful appearance, and the corrosion resistance of the fasteners themselves will also be has seen an increase. It can make the fastener itself obtain the anti-corrosion ability to increase the reliability and adaptability of the fastener. Therefore, the quality judgment of the surface treatment of the fastener is mainly to check whether the anti-corrosion ability of the fastener is effectively increased. And whether the extent of increase meets the expected requirements.


The commonly used methods are:
A. Mechanical plating: mainly refers to the use of specific physical and chemical means to impact the surface of the fastener with the powder of the plated metal, so that the plated metal will form a coating on the surface of the fastener through cold welding to reach the surface Treatment effect.
B. Electroplating: Electroplating of fasteners generally includes zinc plating, copper, nickel, chromium, copper-nickel alloy, etc. Immerse the part of the fastener that needs to be electroplated into a specific aqueous solution. The aqueous solution will contain some deposited metal compounds, so that after the current is passed through the aqueous solution, the metal substance in the solution will precipitate and adhere to the immersed part of the fastener .
C. Hot-dip galvanizing: The price of hot-dip galvanizing of fasteners is higher than that of electroplating, about 1.5 to 2 yuan per kilogram. Hot-dip galvanizing of fasteners is to immerse fasteners of carbon steel components into a plating bath of molten zinc with a heat of about 510°C, so that the iron-zinc alloy on the surface of the fasteners will be converted into passivated zinc. Obtain the surface treatment effect.