Ideal for outdoor use, galvanized steel is coated with zinc oxide to prevent rust. Zinc oxide provides a protective coating to prevent rust. Zinc oxide coating compounds take longer to corrode than non-galvanized steel. As a cost-effective process, galvanized steel gives you a maintenance-free material option for a variety of industries.


What does Galvanized mean?

Galvanizing or galvanizing is a manufacturing process in which a coating of zinc is applied to steel or iron to provide protection and prevent rust. There are several galvanizing processes available, but the most common method is hot dip galvanizing.


How Does Galvanization Work?

Typically, manufacturers dip the steel in molten zinc, which bonds to the steel like any other alloy. This makes zinc more than just a protective coating, as it becomes part of the chemical composition of steel. The inside might be steel and the outside might be zinc, but in between is a gradient mixture of steel and zinc that combines the properties of both metals.


Hot dip galvanizing is the most common form of galvanizing.

You can also spray zinc onto steel, but this method produces a weaker zinc layer.


How Does Galvanizing Protect the Base Metal Underneath?

The zinc coating prevents corrosive substances such as acids (such as acid rain) from reaching the metal below.


Galvanized to prevent rust. Zinc will still "sacrificial anode" more easily than base metals when the coating gets scratched - this keeps it from rusting.

Learn more about how and why metals rust in our blog: Which Metals Rust?


Zinc corrodes protective metals faster than base metals. A special ingredient called "chromate" is sometimes added to galvanized metal, which causes it to corrode faster. It sounds like this might not be what you want to happen, but keep in mind that corrosion of the zinc before the metal is what protects the metal underneath from rusting.


Will galvanized steel rust?

While galvanized steel provides a protective zinc oxide barrier, eventually even galvanized steel will rust. The question remains how fast galvanized steel will rust, and some galvanizations last 50 years or more. Some factors that increase corrosion include:


Outdoor environmental issues such as salt water or humidity

Atmospheric factors such as natural gas or acid rain

temperature fluctuations

air pollution


Gi Sheet Price

Generally speaking, galvanized steel will cost a little more than standard steel due to the added process. The heavier the coating, the higher the cost.


With on-site metal cutting services and partnerships with reputable steel suppliers, WanJuan Steel can provide you with the galvanized steel products you need for today's projects.