Through the black passivation liquid treatment (c2D) containing silver salt or copper salt, a black passivation film is formed with a thickness of about 10-15μm. The cost is high but the appearance is unique.

Use colored zinc passivation (c2C), coating thickness 8-15μm, salt spray test can reach more than 72 hours, colorful appearance, better anti-corrosion performance.

GB/T 882-2008 “Pin” standard, nominal diameter 3-100mm, materials include carbon steel, stainless steel, etc., electrogalvanized layer thickness 5-12μm, in line with c1B or c1A post-treatment requirements.

The color zinc passivation process (c2C) is adopted, the coating thickness is 8-15μm, and the corrosion resistance of the salt spray test is more than 72 hours, which has both anti-corrosion and decorative functions.

It consists of countersunk bolts, expansion tubes, flat washers, spring washers and hexagonal nuts. The material is mostly carbon steel (such as Q235), and the thickness of the electrogalvanized layer is 5-12μm, which meets ISO 1461 or GB/T 13912-2002 standards.

Rainbow chromate passivation (c2C) is performed on the basis of electrogalvanizing to form a colored passivation film with a thickness of about 8-15μm. The salt spray test can last for more than 72 hours without white rust.

Made of Q235 carbon steel and other materials, the surface is electro-galvanized, and the coating thickness is usually 5-12μm, which meets the post-treatment requirements of c1B (blue-white zinc) or c1A (bright zinc) in GB/T 13911-92 standard.