The surface treatment of fasteners refers to the process of forming a covering layer on the surface of fasteners by certain methods. After surface treatment, fasteners can present a more beautiful appearance, and the corrosion resistance of fasteners themselves Ability will also improve. The surface treatment methods of fasteners are as follows.
1. Electroplating of fasteners
The electroplating of fasteners refers to immersing the part of the fastener that needs to be electroplated in a specific aqueous solution. The aqueous solution will contain some deposited metal compounds, so that after the current passes through the aqueous solution, the metal substances in the solution will be precipitated and attached to the surface. on the immersed part of the fastener. Electroplating of fasteners generally includes galvanized, copper, nickel, chromium, copper-nickel alloy, etc.
2. Hot-dip galvanizing of fasteners
The hot-dip galvanizing of fasteners is to immerse the fasteners of carbon steel components into a zinc-dissolving bath at a temperature of about 510 ° C, so that the iron-zinc alloy on the surface of the fasteners will be converted into passivated zinc, thereby Get a finish. The price of hot-dip galvanizing treatment of fasteners is higher than that of electroplating, which is about 1.5 to 2 yuan per kilogram.
3. Mechanical plating of fasteners
The mechanical plating of fasteners refers to impacting the surface of the fasteners with the powder of the coating metal through specific physical and chemical means, so that the coating metal forms a coating on the surface of the fasteners through cold welding to reach the surface. processing effect. Mechanical plating of fasteners is mainly applicable to spare parts such as screws, nuts and washers.
The main purpose of the surface treatment of fasteners is to make the fastener itself anti-corrosion, so as to increase the reliability and adaptability of the fastener. Therefore, the quality judgment of the surface treatment of fasteners is mainly to check Whether the anti-corrosion ability of fasteners is effectively increased, and whether the increase meets the expected requirements.