Dongguan Heat Treatment Factory: Blackening is a commonly used chemical surface treatment method, which works by forming an oxide film on the metal surface to isolate air and prevent rust. Blackening treatment can be used when appearance requirements are not high, and the blackening of steel parts is also known as bluing. Do not exceed the specified temperature when using the oven. According to the phosphatizing mechanism, oxidizers and accelerators can increase the phosphatizing speed and improve the quality of phosphatizing. Common oxidizers and accelerators include salts, chlorates, sulfites, peroxides, and organic oxidizers.

General salt is used for high-temperature phosphatizing, chlorates for medium-temperature phosphatizing, and sulfites and organic oxidizers are mainly used for low-temperature phosphatizing. Peroxides like H2O2, due to their instability, are rarely used. When water needs to be added to the chemical degreaser and acid tanks during operation, it must be slowly added from a distance using a rubber hose. This improves corrosion resistance. Although the phosphatizing film is thin, as a non-metallic, non-conductive insulating layer, it transforms the excellent conductors on the surface of metal workpieces into poor conductors, inhibiting the formation of micro-batteries on the surface of the metal workpieces, thereby effectively preventing the corrosion of the coating.