Within many steel projects, it’s vital for your metal to be protected from the risk of corrosion. One of the most popular methods for doing this is called galvanizing, which is a process that involves applying a thin coating of zinc to metal to help shield it from the surrounding environment.

At Wasatch Steel, we can help with the sorts of metals that are best for galvanizing along with the processes you need to get it done. Here are some of the basics you need to know.

Galvanizing Basics

As you drive around in your car, take note of things like street signs and lamp posts – a high percentage of these will have a mute, silver color. This silver is actually zinc coating, and this metal has been galvanized. This means its thicker metal base has been coated with zinc to help protect it from the rigors of that environment.

Why Do It?

Galvanizing steel gives it anti-corrosion properties. Without this coating, it would be exposed to the elements, allowing it to oxidize and corrode much faster. Galvanized steel is often a more cost-effective alternative to using austenitic stainless steel or aluminum to avoid corrosion.

How Galvanizing Works

Galvanizing protects metal in more than one way. For starters, it creates a protective coating that prevents corrosion. In addition, it can also protect metal through “galvanic corrosion,” a process where two metals of a different makeup are placed into contact with one another with an electrolyte (such as salt water) present.

One metal becomes the anode, and the other becomes the cathode. The anode corrodes more rapidly than it would normally, while the cathode does so more slowly. Zinc has an affinity toward being the anode when it contacts many metals, meaning it can slow the corrosion of the base metal, or cathode. That’s why zinc is so often used in galvanizing.

Methods

There are a few methods for galvanizing metal:

• Hot-dip galvanizing: This involves dipping base metal into a pool of zinc. It’s an economical method that can be performed quickly and to complex shapes, but the final coating can be inconsistent compared to other processes.
• Pre-galvanizing: Similar to hot-dip galvanizing, but is performed at the steel mill on products that have a specific shape already.
• Electrogalvanizing: A process that uses an electrical current in an electrolyte solution to transfer zinc onto the base metal. This brings benefits like uniform coating and precise thickness, but coating is often thinner than hot-dip methods can achieve.

For more on galvanizing steel, or to learn about any of our steel services, speak to the pros at Wasatch Steel today.