Prepainted GI Steel Coil PPGI PPGL Color Coated Galvanized Corrugated Metal Roofing Sheet In Coil

Hot dipped galvanized steel sheet & coil is made of carbon steel coated in zinc utilizing the hot-dip process. The end result of this process is a layer of zinc on each side of the steel sheet or coil that is tightly adhered to the steel through the formation of an iron-zinc alloy bonding layer. This bonding layer is formed by a diffusion process while the heated steel is in contact with molten zinc.

Galvanized steel is defined as a carbon steel sheet coated with zinc on both sides. There are two main processes used to produce galvanized steel: continuous hot dipping and electro-galvanizing.
The hot dipping process consists of passing the steel through a bath of molten zinc, while the electro-galvanizing process consists of the application of zinc through electrolytic disposition. The result is a layer of zinc tightly adhering to the base metal through an iron-zinc bonding layer. Our hot-dipped galvanized products are manufactured to ASTM A653 specifications; our electro-galvanized products conform to ASTM A879 specifications.
A zinc coating is one of the most effective and economical methods of protecting bare steel from a corroding environment. The zinc not only serves as a barrier between the steel and the environment, but it will also sacrifice itself to protect the underlying steel sheet. Sacrificial or galvanic protection occurs when two dissimilar metals are in contact and coupled with water and oxygen. Zinc corrodes preferentially to the iron in steel. This protection prevents corrosion of the steel in areas not covered with zinc. Thus, the spread of corrosion from cut edges, drill holes, etc. is minimized.