热浸镀锌彩钢板常用的钢种有：普通商用卷材（CQ）、结构镀锌板（HSLA）、冲压镀锌板（DQ）、深冲热镀锌板（DDQ）、烘烤硬化热镀锌板（BH）、双相钢（DP）、TRIP钢（相变诱导塑性钢）等。The production process of hot-dip galvanizing plate mainly includes: raw plate preparation → pre plating treatment → hot dip coating → post plating treatment → finished product inspection, etc., which is usually carried out according to the pretreatment method of electroplating
Hot dip galvanizing process can be divided into two categories: wet process (single steel hot galvanizing method), off-line annealing method (single steel hot-dip galvanizing method), wheel method (continuous hot-dip galvanizing method for strip steel),
Sendzimir method for on-line annealing (shielding gas method) adopts improved Sendzimir method, American Iron and Steel Federation (same as Kawasaki method in Japan), selas method and Sharon method.
Zinc is soluble in acids and bases, so it is called amphoteric metal. The standard electrode potential of zinc is negative than that of steel. When the substrate is steel, when the coating is damaged or corroded to form an iron zinc galvanic cell, the zinc coating belongs to the anode coating, which protects the steel by sacrificial dissolution of zinc. Therefore, the zinc coating on the steel surface is not only a mechanical protection, but also an electrochemical protection to prevent corrosion of the substrate, even if the zinc coating is incomplete. The corrosion resistance of zinc coating largely depends on the corrosion resistance of passive film. The corrosion resistance of passivated zinc coating can be increased by 8-20 times.
There are two kinds of zinc plating bath: cyanide plating solution and non cyanide plating solution. Cyanide plating bath is divided into micro cyanide, low cyanide, medium cyanide and high cyanide. Cyanide free plating bath includes alkaline zincate bath, ammonium salt plating bath, sulfate plating bath and ammonia free chloride plating bath. Cyaniding zinc plating solution has good bath performance and bright and clean coating, which has been used for a long time in production. However, due to its high toxicity and serious environmental pollution, low cyanide, micro cyanide and non cyanide zinc plating solutions have been used in recent years.
The mechanical properties of hot rolled steel plate are much lower than those of cold working and forging, but they have better toughness and ductility. The strength of hot-rolled plate is relatively low, the surface quality (oxidation finish is low), but the plasticity is good. Generally, it is medium thick plate. Cold rolled sheet: high strength, high hardness, high surface finish, generally thin steel plate, can be used as stamping plate. Cold rolled steel sheet has low toughness due to work hardening to a certain extent, but it can obtain better yield ratio, which can be used for cold bending of spring sheet and other parts. At the same time, because the yield point is close to the tensile strength, the danger can not be foreseen in the process of use, and accidents are prone to occur when the load exceeds the allowable load.
Hot dip galvanized sheet is mainly used in construction, home appliances, automobile, machinery, electronics, light industry and other industries.
The commonly used steel grades of hot dip galvanized sheet are: common commercial coil (CQ), structural galvanized sheet (HSLA), stamping galvanized sheet (DQ), deep drawing hot dip galvanized sheet (DDQ), bake hardening hot dip galvanized sheet (BH), dual phase steel (DP), TRIP steel (phase transformation induced plasticity steel), etc.