Hot-dip galvanized steel coil: a thin steel coil is immersed in a molten zinc tank to adhere a layer of zinc to its surface. It is mainly produced by continuous galvanizing process.
Alloy galvanized steel coil: manufactured by hot dipping method, heated to about 500℃ after leaving the tank, to form an alloy film of zinc and iron, with good paint adhesion and weldability.
Electrogalvanized steel coil: manufactured by electroplating method, with good processability, but the coating is thinner and the corrosion resistance is not as good as hot-dip galvanized coil.
Single-sided and double-sided differential galvanized steel coil: single-sided galvanized steel coil is galvanized only on one side, with better adaptability; double-sided differential galvanized steel coil is coated with a thin layer of zinc on the other side.
Alloy and composite galvanized steel coil: steel coils made of alloy or even composite plated with zinc and other metals, with excellent rust prevention and good coating performance.
Classification by coating type
Galvanizing: achieved by immersing the prepared strip into a bath of molten alloy containing at least 99% zinc.
Zinc-iron coating: the strip is immersed in a molten zinc bath and further annealed to form a zinc-iron coating with an iron content of 8-12%.
Zinc-aluminum coating: coated by immersing the rolled steel in a bath of zinc and about 5% aluminum and a small amount of mixed metal.
Aluminum-zinc coating: formed by immersing the steel in a molten metal bath consisting of 55% aluminum and 1.6% silicon (the rest is absorbed by zinc).
Aluminum-silicon coating: formed by immersing the steel in a molten metal bath containing aluminum and 8-11% silicon.
Classification by surface treatment
Passivation: reduces rust under humid storage and transportation conditions, but the corrosion protection is limited.
Oiling: reduces rust under humid storage and transportation conditions, and the oil layer can be removed with a degreaser.
Lacquer seal: provides additional corrosion protection and improves lubricity during forming.
Phosphating: Improve the adhesion and corrosion resistance of the coating.
No treatment: No surface treatment.
Classification by surface structure
Normal spangles: A coating with obvious spangle morphology formed by the free growth of zinc grains.
Small spangles: Zinc grains are artificially restricted to form a coating with as small a spangle as possible.
No spangles: No visible spangle morphology, uniform surface.
Zinc-iron alloy: The entire coating forms an alloy layer of zinc and iron, with a dark gray appearance and no metallic luster.
Classification by use
General use: Galvanized coils suitable for general use.
Roofing: Galvanized coils used for roof construction.
Building exterior panels: Galvanized coils used for building exterior panels.
Structural use: Galvanized coils used for structural parts.
Roofing: Galvanized coils used for the manufacture of roofing.
Stretching: Galvanized coils suitable for stretching processing.
Deep drawing: galvanized coil suitable for deep drawing process.