How can steel be protected from corrosion?

The most common surface protection methods for steel are:

Anti corrosive paint coating
Hot dip galvanizing
Electroplating
Spray galvanizing
Chromium plating
Aluminium spraying
Rubberising
Coil coating of sheet steel

The most common metallic coating used to protect steel construction products is hot dip galvanising. Very simply, the process involves coating the surface of the steel with a very thin coating of a corrosion-resistant metal, usually zinc or an aluminium/zinc alloy.

Zinc coating
Zinc coating can be executed by:
Hot-dip zinc coating
Electroplating
Spray galvanizing
Zinc-rich paint

The corrosion resistance of zinc coating varies depending on zinc coating thickness. Hot dip zinc coating (hot dip galvanizing) is therefore the most common and most important form of zinc coating for steel structures.