Carbon Steel Galvanized Steel A325 Square Head Metal Bolt GR2 GR5 193 B7 Zinc Black

Metal color zinc plating refers to a treatment carried out in a chromate solution on the galvanized layer to obtain a rainbow-colored passivation film. Its structure is generally believed to be a complex mixture composed of chromium (III) basic chromate, zinc (III) basic chromate, chromium (III) chromate, zinc (III) chromate, and oxides of zinc and chromium. Passivation treatment of the galvanized layer to a rainbow color can significantly enhance its corrosion resistance. It is mainly used for the protection of steel parts.

• Mild Steel: Contains less than 0.3% carbon, highly ductile and malleable, used in automotive body panels, wire, and sheet metal.
• Medium Carbon Steel: Ranges from 0.3% to 0.6% carbon, provides balance of strength and ductility, used in shafts, axles and gears.
• High Carbon Steel: Contains more than 0.6% carbon, known for high hardness and wear resistance, used in cutting tools and springs.
• Ultra-High Carbon Steels: Carbon content over 1.0%, excellent hardness and wear resistance, used in ball bearings and precision components.

Bolts are mechanical parts, cylindrical threaded fasteners with nuts. They are used to fasten two parts with through holes and allow for detachable connections. Applications include:

Ordinary bolt heads are very thick and difficult to deform. Flange bolts with thinner parts can be slightly deformed for a more secure lock. The flange plate also serves as a fastening component, allowing use with special tools in confined spaces. Additionally, the flange top flat pad provides safer use with softer, non-wear-resistant materials by preventing perforation.