Why is hot-dip galvanizing applied to the surfaces of steel products?

Steel is prone to rusting and even complete damage when exposed to air, water, or soil. Approximately one-tenth of the total steel production is lost annually due to corrosion. Therefore, protective coatings or platings are necessary to shield steel from corrosion. Hot-dip galvanizing is one such method. Zinc is resistant to changes in dry air, and in humid air, it forms a dense layer of basic zinc carbonate on its surface, which protects the underlying zinc from further corrosion. Furthermore, if the galvanized layer is damaged for some reason, exposing a relatively small area of the steel substrate, a micro-galvanic cell forms between the zinc and the steel substrate, making the steel substrate the cathode and thus protected. The corrosion rate of zinc in the atmosphere is one-fifteenth of that of steel, indicating that the lifespan of the zinc protective layer is relatively long. Additionally, compared to other corrosion-resistant metallic materials, zinc is relatively inexpensive. Therefore, hot-dip galvanizing steel is both durable and cost-effective.