Galvanized coil, a thin steel sheet that is dipped in a bath of molten zinc to adhere a layer of zinc 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.

Zinc Coating

(1) 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) 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:

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) 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.

Advantages

The main advantage of galvanized coil is that the surface oxidation resistance is strong, which can strengthen the corrosion resistance of parts. In addition, the surface of galvanized roll is clean and beautiful, which enhances the decorative material. Therefore, galvanized products are becoming more and more indispensable materials in manufacturing industry.