Galvanized Coil

　　Galvanized coil, a thin steel sheet that is dipped in a bath of molten zinc so that a layer of zinc is adhered to its surface. It is mainly produced by the continuous galvanizing process, that is, the coiled steel plate is continuously dipped in the galvanizing tank with molten zinc to make galvanized steel plate; alloyed galvanized steel plate. This kind of steel panel is also made by hot dip method, but it is heated to about 500℃ immediately after coming out of the tank, so that it can form an alloy film of zinc and iron. This galvanized coil has good paint adhesion and weldability.

　　Plating definition

　　(1) Normal spangle coating spangle coating

　　During the normal solidification process of the zinc layer, the zinc grains grow freely and form a coating with obvious spangle morphology.

　　(2) Minimized spangle coating

　　During the solidification process of the zinc layer, the zinc grains are artificially restricted to form a spangle coating as small as possible.

　　(3) No spangle coating spangle-free

　　By adjusting the chemical composition of the plating solution, there is no visible spangle morphology and a uniform coating on the surface.

　　(4) zinc-iron alloy coating zinc-iron alloy coating

　　Heat treatment is carried out on the steel strip after passing through the galvanizing bath, so that the entire coating forms an alloy layer of zinc and iron. The appearance of this coating is dark gray, without metallic luster, and it is easy to pulverize during the violent forming process. Except for cleaning, coatings that can be painted directly without further treatment.

　　(5) differential coating

　　For both sides of the galvanized steel sheet, coatings with different zinc layer weights are required.

　　(6) Smooth skin pass

　　Skin pass is a cold rolling process with a small amount of deformation on galvanized steel sheets for one or more of the following purposes.

　　Improve the surface appearance of galvanized steel sheets or be suitable for decorative coatings; temporarily minimize the phenomenon of slip lines (Lüders lines) or creases produced during processing of finished products, etc.