When hot-dip galvanized steel is painted, the duplex system provides a more sophisticated manner of corrosion protection. The galvanized coating protects the base steel by providing both cathodic and barrier protection. The paint coating acts as a barrier protection for the hot-dip galvanized coating and significantly reduces the corrosion rate of the zinc. The increased lifetime that can be provided with a combination of paint over galvanized steel makes this type of corrosion protection system very attractive for structures designed to last a long time in aggressive atmospheres.

When hot-dip galvanized steel is painted, the duplex system provides a more sophisticated manner of corrosion protection. The galvanized coating protects the base steel by providing both cathodic and barrier protection. The paint coating acts as a barrier protection for the hot-dip galvanized coating and significantly reduces the corrosion rate of the zinc. The increased lifetime that can be provided with a combination of paint over galvanized steel makes this type of corrosion protection system very attractive for structures designed to last a long time in aggressive atmospheres.