The galvanized steel coil is coated on the zinc layer, the outermost layer is zinc, but the continuous layer is a mixture of zinc and iron, and the inner layer is pure steel. These multilayer structures make the metal have amazing corrosion resistance. Zinc can also be used as a "sacrificial layer" to protect steel. If the rust is really on the surface of the galvanized steel coil, the zinc will be corroded first. This allows zinc to be coated on nicks or scratches to prevent rust from reaching the steel. For countless outdoor, marine or industrial applications, galvanized steel coil is an essential manufacturing component.