The salinity of seawater typically ranges from 1% to 25%, with 3.5% commonly used for calculations. Seawater contains substantial amounts of oxygen, nitrogen, carbon dioxide, and other elements that accelerate the corrosion of zinc layers. Chloride ions (approximately 55% of the total ion count) hinder the formation of protective films and enhance corrosion, while magnesium and calcium ions readily react with zinc layers to form insoluble salts, promoting the formation of protective films and gradually reducing the corrosion rate.
The products resulting from the corrosion of zinc layers in seawater include carbonates, hydroxides, chlorides, and other components. The corrosion rate of zinc layers in seawater generally ranges from 50 to 650 milligrams per square decimeter per year.
