- Sep 30, 2018 -
The bonding force and appearance of the trivalent chromium passivation film are closely related to the galvanizing process. Whether it is hexavalent chromium passivation or trivalent chromium passivation, the adhesion of alkaline cyanide-free galvanized passivation film is better than acid galvanizing. Although the acid galvanizing layer can also achieve the color of the acid galvanizing layer, the operation requirements are higher, the washing requirement is cleaner and thorough, and the passivation time cannot be too long, otherwise the passivation film is easy to yellow. Cyanide-free zinc plating is mainly zinc chloride and zincate zinc plating. The advantages of chloride galvanizing are excellent decorative properties, high current efficiency, poor throwing ability, and the layered structure of the coating makes the trivalent chrome blue and white passivation film less corrosion resistant than zincate galvanized. The advantage of zincate galvanizing is that the electrolyte has good deep plating ability and dispersing ability, and the plated crystal grains are columnar, so the trivalent chromium blue white passivation film has excellent corrosion resistance, from the functional point of view The corrosion resistance of zincate galvanized blue-white passivation film is greater than that of acid chloride galvanized blue-white passivation film. And from the softness of the coating, the new generation of zincate galvanizing is softer than chloride galvanizing.