• 1. Protective coating method, covering the surface of metal parts with a protective layer to isolate the metal parts from the surrounding corrosive medium to prevent corrosion. Coat the surface of metal parts with machine oil, petroleum jelly, paint or cover with enamel, plastic and other corrosion-resistant non-metallic materials.
  • 2. Electroplating method, using methods such as electroplating, hot-dipping, spraying, etc., to plate a layer of metal that is not easily corroded, such as zinc, tin, chromium, nickel, etc., on the surface of metal parts. These metals are often oxidized to form a dense oxide film to prevent corrosion of metal parts such as water and air.
  • 3. Use chemical methods to form a fine and stable oxide film on the surface of metal parts. For example, a fine black ferroferric oxide film is formed on the surface of machine parts, guns and other metal parts.
  • 4. The electrochemical protection method uses the principle of galvanic cell to protect the metal, trying to eliminate the galvanic corrosion that causes galvanic corrosion. Electrochemical protection law is divided into two categories: anode protection and cathodic protection. The cathodic protection method is more widely used. Treat corrosive media. Eliminate corrosive media, such as cleaning metal equipment frequently, placing desiccant in metal parts, and adding a small amount of corrosion inhibitor that can slow down the corrosion rate in corrosive media.