Cold-rolled sheets are rolled from hot-rolled coils at room temperature below recrystallization temperature. It is mostly used in automobile manufacturing, electrical products and so on.
In the production process, there are no defects such as pitting and oxide scale, which often occur in hot rolling, because there is no heating, and the surface quality is good and the finish is high. Moreover, the size accuracy of cold rolled products is high, and the properties and structure of products can meet some special requirements, such as electromagnetic properties, deep drawing properties and so on.
In the automotive industry, it is used for automotive body, shell, inner plate, bottom plate, etc. China vigorously develops power, transportation, communications, energy and urban infrastructure. With the strong development of construction, household appliances and automobile industry, galvanizing industry in China is facing unprecedented opportunities and huge market.
In the past two decades, the continuous hot-dip galvanizing technology, equipment and corresponding control methods of steel strip have been greatly developed, which makes galvanized sheet meet the stringent requirements of automobile panel and household appliances panel, and has the potential to be replaced by galvanized alloy steel strip because of its cheaper price and excellent corrosion resistance than galvanized alloy steel strip. This subject intends to draw lessons from the advanced technology and experience of foreign high performance hot-dip galvanizing production technology and equipment development. Through technological innovation, optimization design, precision manufacturing and foreign technical cooperation, it will break through the bottleneck restricting the development of production technology and equipment of high performance hot-dip galvanized steel sheet for automobiles in China. Meanwhile, the significance and prospects of the development of hot dip galvanizing technology in the sustainable development of national economy, energy saving and mineral resources are discussed.