Galvanizing is one of the most widely used methods to protect metals from corrosion. It includes coating a thin layer of zinc on the thick base metal to help it avoid the influence of the surrounding environment. Next time you are in the car, look at the street signs and lamp posts you pass by. Many of them will have a matte silver on their bodies. This “silver” is actually a coating of zinc.
Quite simply, galvanize a metal gives it anti-corrosion properties. Without the protective zinc coating, the metal would remain exposed to the elements and potentially oxidize and corrode much faster. Galvanize Steel is a cost effective alternative to using materials such as austenitic stainless steel or aluminium in order to prevent corrosion.
Galvanizing can protect metal is a number of ways. Firstly, it creates a protective coating that shields the metal from the surrounding environment. The layer of zinc prevents water and moisture and other elements in the air from corroding the steel underneath. Should the zinc coating be scratched deep enough, the metal would become exposed and susceptible to corrosion.
Galvanizing can also protect metal through a process called “galvanic corrosion”. Galvanic corrosion occurs when two metals of a different electrochemical make up are placed into contact with one another with an electrolyte present, such as salty water. Depending on the atomic structure of the two metals, one metal is the anode and the other is the cathode. The anode corrodes more rapidly than it would by itself and the cathode corrodes at a slower pace than it would by itself. The reason zinc is used for galvanize is because it has an affinity towards being the anode when in contact with many different types of metals. Since the zinc coating in contact with the base metal is usually the anode, it slows the corrosion of the base metal, or the cathode.
There are several different processes for galvanizing metal: