Galvanized refers to the surface treatment technology of plating zinc on the surface of metal, alloy or other materials to play the role of beauty, rust prevention, etc. The main method is thermal galvanized.

Zinc is easily soluble in acid and alkali, so it is called amphoteric metal. Zinc hardly changes in dry air. In humid air, dense basic zinc carbonate film will be formed on the surface of zinc. In the atmosphere containing sulfur dioxide, hydrogen sulfide and marine, the corrosion resistance of zinc is poor, especially in the high temperature and high humidity atmosphere containing organic acid, zinc coating is very easy to be corroded. The standard electrode potential of zinc is - 0.76v. For the steel substrate, zinc coating belongs to anode coating, which is mainly used to prevent the corrosion of steel. The protection performance is closely related to the coating thickness. After passivation, dyeing or coating, the protective and decorative properties of zinc coating can be significantly improved.

With the development of galvanized technology and the use of high-performance galvanized brightener, galvanized has entered the protection decoration application from the simple protection purpose.

There are two kinds of galvanized solution: cyanide plating solution and non cyanide plating solution. Cyanide solution is divided into micro cyanide, low cyanide, medium cyanide and high cyanide. Cyanide free solutions include alkaline zincate solution, ammonium solution, sulfate solution and ammonia free chloride solution. The cyanide galvanized solution has good plating ability and the obtained coating is smooth and fine, which has been used for a long time in production.