Abstract
Hot-dip galvanized steel was exposed to sea air, sea spray, tidal flow, and continuous immersion in seawater in order to determine its corrosion resistance in various marine environments.
Corrosion resistance was evaluated by surface observation, microscopic observation of a cross section of the galvanized coating, and measurement of corrosion weight loss. The corrosion rate in a relatively dry marine environment (exposure to sea air) was approximately equal to the corrosion rate in rural areas. The corrosion rate in a wet marine environment (immersion in seawater) was high when compared with the corrosion rate when exposed to sea air, but the corrosion rate decreased with time. The corrosion rate under the alternating wet/dry conditions encountered in the sea spray and tidal flow exposure sites was high, and corrosion of the steel base was observed before zinc in the coating was depleted.
These exposure tests served to confirm the effectiveness of a hot-dip galvanized coating in various marine environments.
