Classification of steel sheets (1)

Classification of steel sheets

(1) Classification by surface characteristics (1) Galvanized sheet (hot-dip galvanized sheet, electro-galvanized sheet): In order to prevent the surface of the steel sheet from corrosion and extend its service life, a layer of metal zinc is applied to the surface of the steel sheet. Hot-dip galvanizing: The thin steel sheet is immersed in a molten zinc bath to make a thin layer of zinc adhere to its surface. At present, the main production process is continuous galvanizing, that is, the rolled steel sheet is continuously immersed in a molten zinc plating bath to make a galvanized steel sheet. Electro-galvanized: This galvanized steel sheet manufactured by electroplating has good processability. However, the coating is thin and the corrosion resistance is not as good as that of hot-dip galvanized sheet.

(2) Tinplate: A cold-rolled thin steel sheet with an extremely thin layer of metal tin on both sides. It combines the hardness and strength of steel with the weldability, corrosion resistance and bright appearance of tin. Tinplate has the advantages of being odorless, non-toxic, light in weight and easy to process and shape. Printing different patterns can also beautify the product, so it has been widely used in the food canning industry, electronic devices, chemical paint and other industries.

(3) Composite steel plate: According to its combination type, it can be divided into two categories, namely metal composite steel plate and non-metal composite steel plate.

Metal composite steel plate is a steel plate with other metal coatings on the surface, such as stainless steel composite steel plate, titanium composite steel plate, copper composite steel plate and aluminum composite steel plate.

Non-metal composite steel plate is a composite of base steel plate and viscoelastic resin with excellent vibration reduction performance, such as lightweight composite steel plate and vibration reduction composite steel plate.

(4) Color coated steel plate: commonly known as color steel plate, with high-quality cold-rolled steel plate, hot-dip galvanized steel plate or aluminum-zinc-coated steel plate as the substrate, after surface degreasing, phosphating, chromate treatment, coating with organic coating and baking.

It has the characteristics of light weight, high strength, bright color and good durability. It is widely used in construction, home appliances, decoration, automobile and other fields.

The strength of color steel plate depends on the substrate material and thickness, and the durability depends on the plating (galvanizing amount 318g/m2) and surface coating. The coatings include polyester (PE), silicone resin (SMP), high weather-resistant polyester (HDP), polyvinylidene fluoride (PVDF), etc. The coating thickness is more than 25um. The coating structure includes two coatings and one baking, two coatings and two baking, etc. The maintenance-free service life can be 20-30 years depending on the ambient atmosphere.