What Is The Production Process Of Hot-dip Galvanized Sheet?

Galvanized steel sheet is a composite material of steel and zinc. Galvanized products combine the advantages of both materials. Composite materials have the strength and ductility of steel, plus a corrosion-resistant coating. Widely used in construction, home appliances, automobiles and other industrial fields. In the atmosphere, zinc is much more resistant to corrosion than steel. Under normal conditions, zinc is 25 times more resistant to corrosion than steel. Hot dipping and electroplating are the two main processes for galvanizing steel sheets.

Hot-dip galvanizing is a more common and cost-effective process for treating steel for corrosion protection. Hot-dip galvanized sheet technology can avoid corrosion of steel process, improve service life, save energy consumption, and has an irreplaceable role. Hot-dip galvanized sheet is a resource-saving development prospect. The corrosion resistance of hot-dip galvanized sheet comes from the standard potential of zinc, which is lower than the standard electrode potential of iron. Therefore, maintaining the steel base by cathodically protecting the zinc layer in water or wet cold gas can greatly increase the service life of the steel process.

During the hot-dip galvanizing process, when the steel plate passes through the zinc pot, the zinc liquid adheres to the surface of the steel plate, and the air knife blows off the excess zinc liquid, so it is easy to produce thick-coated steel plates. In recent years, in order to reduce production costs and meet environmental protection requirements, domestic automobile and home appliance companies have gradually adopted hot-dip galvanized steel sheets instead of galvanized steel sheets. The surface quality of hot-dip galvanized sheet is better, the coating is evenly distributed, and its weldability, coating and stamping formability are better than hot-dip galvanized sheet; single-sided, double-sided or different thickness coatings can be easily processed in the production process switch. However, during galvanizing, zinc ions in the plating solution are transported to the steel sheet by an electric current. The thicker the coating, the more power consumed and the higher the cost.

The electrochemical potential of hot-dip galvanized sheet coating is more negative than that of steel, and the coating of hot-dip galvanized sheet has excellent electrochemical protection performance. The coating is thick and dense, the adhesion between the coating and the steel substrate is strong, and the durability is good. The service life of hot-dip galvanized steel with a zinc content of 600g/m2 can reach more than 30 years. The hot-dip galvanized layer of steel requires no maintenance during use. The hot-dip galvanizing process is simple and has strong adaptability to the shape and size of steel. In addition to steel sheets and strips, the hot-dip galvanizing process is also widely used in steel pipes, steel wires, and structural parts with high productivity. Compared with other protective coatings, zinc coating has strong economic competitiveness, especially for long-term use parts, the cost of hot-dip galvanized coating is much lower than that of paint coating.