Common surface treatment methods for fasteners such as screws and nuts, and resistant screws

During the production and processing of screws, they all need to undergo surface treatment. What is the surface treatment? Surface treatment is the process of forming a covering layer on the surface of a workpiece through certain methods, with the aim of giving the product a beautiful and corrosion-resistant surface. The surface treatment methods used are summarized as follows:
1. Electroplating: Immerse the electroplated parts in an aqueous solution containing the deposited metal compound, and use an electric current to pass through the plating solution, causing the electroplated metal to precipitate and deposit on the parts. Generally, electroplating includes zinc plating, copper plating, nickel plating, chromium plating, copper nickel alloy plating, and sometimes includes blackening (bluening), phosphating, etc.
Screw electroplating
2. Hot-dip galvanization: It is completed by immersing carbon steel parts in a bath of molten zinc with a temperature of about 510 ℃. The result is that the iron zinc alloy on the surface of the steel parts gradually becomes passive zinc on the outer surface of the product. Hot dip aluminum plating is a similar process.
bolt Hot-dip galvanization
3. Mechanical plating: Impacting the surface of a product by coating metal particles and cold welding the coating onto the surface of the product.
4. Durable treatment: It can pass strict 100 grid tests and meet high salt spray requirements. It can be applied to industries with high requirements such as toys, headphones, and mobile phones.