Blue zinc plating and green zinc plating: The process is roughly the same as that of white zinc. Blue zinc is a passivated zinc oxide film containing trivalent chromium of 0.5-0.6 mg/dm2. Green passivation is also called penta-acid passivation, which can obtain a thick grass green film. The passivation solution contains phosphate ions, and the obtained oily grass green film is a complex protective film composed of chromate and phosphate.
For its corrosion resistance, blue zinc is better than white zinc, and green zinc is better than blue zinc. The color of blue zinc is relatively close to that of white zinc, which is widely used in the industry, and can also be used as an alternative process screw in product design.
