When you need steel products that are corrosion-resistant, you have two primary options: stainless and galvanized. Both are steel alloys designed to resist corrosion, but they have some key differences that make them suitable for different applications.
The first difference between stainless and galvanized steel is their composition. In general, stainless steel is an iron alloy with a minimum of 10.5% chromium. Many stainless steel alloys include other elements, such as nickel, manganese, and molybdenum, to enhance their properties and change their characteristics. Galvanized steel, on the other hand, is regular steel with a zinc coating to prevent rust and corrosion.
The crucial difference between these two types of steel is their corrosion resistance. Stainless steel’s chromium content reacts with the oxygen in the air or water to create a passive oxide layer that protects it from corrosion in most environments. Galvanized steel, however, only has the layer of zinc to protect it from corrosion. Once the zinc layer corrodes, there is nothing to protect the steel. Depending on the environment, the zinc layer can last for some time, providing an effective barrier against rust and corrosion.
The most obvious difference between galvanized and stainless steel is their appearance. Stainless steel is a shiny, polished metal, while galvanized steel, because of the outer layer of zinc, is a dull, matte gray. The differences in appearance partially contribute to the uses of each type of steel. Stainless steel products are often used in kitchen appliances, architectural features, jewelry, and other applications where aesthetics are important. Galvanized steel is more common in outdoor structures, including fencing and roofing.
While both galvanized and stainless steel are strong materials, stainless steel generally has the edge when it comes to tensile strength. Stainless steel’s higher tensile strength is why it is more common in construction or industrial equipment than galvanized steel. The layer of zinc on galvanized steel protects against weakening from corrosion, but overall, stainless steel is the stronger material.
In most circumstances, stainless steel outperforms galvanized steel, making it the preferred choice for many applications. At Alliant Metals, we provide stainless steel products for applications across several industries. Contact our team at 1-800-543-1453 to learn more about all our products and services.
