Galvanized sheets are coated with a layer of metallic zinc on the surface of thick steel sheets to prevent the surface of thick steel sheets from being corroded and extend their service life. This type of zinc-coated cold-rolled steel sheet is called galvanized sheet. Classification can be divided into the following categories according to manufacturing and processing methods:
①Hot-dip galvanized thick steel plate. The cold-rolled steel plate is infiltrated into the molten zinc bath so that a layer of zinc adheres to the surface of the cold-rolled steel plate. At present, it mainly adopts the continuous hot-dip galvanizing process, that is, the thick steel plate in the coil is continuously immersed in a plating bath containing molten zinc to make a galvanized plate;
②Fine-grain reinforced galvanized sheet. This kind of steel plate is also produced by the hot dip method, but it is heated to about 500°C immediately after coming out of the tank to turn it into an aluminum alloy coating of zinc and iron. This type of galvanized sheet has excellent adhesion to architectural coatings and electric welding properties;
③Electro-galvanized sheet. This kind of galvanized sheet produced by electroplating method has excellent process performance. However, the coating is thin and its corrosion resistance is not as good as that of hot-dip galvanized sheets;
④Single-double-sided galvanized plate and double-sided galvanized plate. Single-sided galvanized sheet is a product that is hot-dip galvanized on only one side. In terms of welding, spraying, anti-rust treatment, production and processing, it has stronger adaptability than double-sided galvanized sheets. In order to get rid of the defect of not being coated with zinc on both sides, there is another kind of galvanized sheet that is coated with chromatographic zinc on the other side, that is, double-sided galvanized sheet;
⑤Aluminum alloy, composite galvanized sheet. It is a thick steel plate made of zinc and other metal materials such as lead, zinc, aluminum alloy or even composite plating. This kind of thick steel plate has both excellent anti-rust treatment properties and excellent spray properties. In addition to the above five types, there are also colorful galvanized sheets, clothing printing spray galvanized sheets, polyethylene laminated galvanized sheets, etc. But at this stage, hot-dip galvanized sheets are still common. According to the main uses, galvanized sheets can be divided into general use, roof use, construction side panel use, structural use, tile ridge board use, drawing use and deep drawing use.
