When it comes to various steel applications in the modern world, rust and corrosion prevention are often some of the most important qualities prioritized. For the many applications where such protections are valuable, two of the most popular metal products utilized are stainless steel and galvanized steel.

At Wasatch Steel, we’re proud to offer a wide range of steel products, from stainless steel tubing to steel bar, steel plate and several other types. One of the most common questions we get from clients who are prioritizing corrosion resistance in their materials: What are the main differences between stainless and galvanized steel for these purposes, and which should I choose for my application? This two-part blog series will dig into everything you need to know about both these materials and their ideal uses.

Stainless Steel Basics

What makes stainless steel different from standard carbon steel or other types? The answer lies in additions that are made to the material to change its chemical makeup, making it more resistant to corrosion.

Carbon steel is usually mostly iron and carbon, but stainless steel adds to this, usually with additions of chromium (sometimes other alloying elements). This element is added during the melting process and prior to forming, changing the chemical properties of the steel in important ways we’ll detail further in just a bit.

Galvanized Steel Basics

Galvanized steel, on the other hand, does not refer to steel that’s had additional alloys added to it – but rather to a steel that has been coated in a layer of zinc. This zinc serves as a protective layer for the underlying steel, helping stop rust or other corrosion risks from ever reaching the metal itself.

Galvanization is generally done well after melting, refining and shaping has already been completed on steel. It may even be completed after manufacturing processes like bending or welding.

Corrosion Resistance Properties

Each of these materials resists corrosion in its own way. Here are the basics:

• Stainless steel: The added chromium, or other alloying elements in certain cases, combines with oxygen present in the surrounding environment of the steel to create a layer of chromium oxide. This chromium oxide prevents the formation of iron oxide, which is the technical name for rust. As long as there’s enough chromium or another alloying element to create this strong layer, corrosion will be prevented.
• Galvanized steel: The zinc layer added to this steel prevents oxygen from making contact with the steel, limiting corrosion risks. Even when this layer is damaged, nearby zinc on the remaining coating is more reactive than the underlying steel, and therefore more likely to attract an oxygen molecule and limit rust.

For more on the differences between stainless and galvanized steel, or to learn about any of our steel products or services, speak to the staff at Wasatch Steel today.