Choosing galvanized steel is one way to prevent corrosion and damage in your steel products. Other solutions do exist such as coating steel with paint, zinc plating, other types of coating, or choosing to build with aluminum instead. However, none of these other options stand the test of time and prevent corrosion better than galvanized steel. Coatings can chip and wear away, and aluminum is not the best choice for all building projects because it is not as strong and durable as steel. One of the main reasons why galvanized steel is the best choice for resisting rust and the elements is because the zinc in galvanized steel offers barrier protection and sacrificial protection.
Barrier Protection. Galvanized steel offer barrier protection before sacrificial protection. The hot dip process of galvanizing steel creates a zinc coating on the outside of the steel which sees the most distress. When the surface of galvanized steel gets damaged, the zinc coating gets damaged first. Regular zinc coating offers the same barrier protection on the surface, but you will not get any protection below the surface like that of galvanized steel. Once the surface zinc coating is damaged on steel which is not galvanized, the underlying steel is exposed and vulnerable to corrosion.
Sacrificial Protection. In addition to barrier protection, galvanized steel offers sacrificial protection. Sacrificial protection is unique to galvanized steel. The zinc coating on galvanized steel bonds deeper than just the surface. This allows for more protection than a zinc plating on steel can offer. When the superficial zinc coating on galvanized steel is penetrated, the galvanized steel below is still protected by zinc. So when exposed to the elements, the corrosion products within the zinc will be redeposited on the steel. This provides another barrier for the steel to resist corrosion.