Galvanized Steel Vs. Stainless

by Richard Rowe

For most applications, galvanized steel will accomplish the same task as stainless. However, your operating conditions, longevity requirements and budget will dictate which one's best for you.

Manufacture

Workers pouring steel in a steel mill.

Stainless steel is made by adding at least 10.5% chromium (by weight) to regular carbon steel, according to the Stainless Steel Industry of North America. To galvanize steel, manufacturers dip the raw carbon steel in a bath of molten zinc, which bonds to the steel's surface in a thin layer.

Function

Wet stainless steel pipes.

Both stainless and galvanized steels prevent corrosion by forming a "sacrificial" layer of protective oxides. Stainless forms an almost invisible layer of chromium oxide and galvanized forms a (comparatively) thick layer of zinc oxide, according the Metallurgical Consultants website.

Longevity

Rusty galvanized steel sheets.

Eventually, the galvanized steel's zinc oxide coating will wear away, leaving it vulnerable to corrosives and weather. Stainless steel contains chromium all the way through, so its protective layer is continually replenished.

Durability

Zinc spraying process to create galvanized steel.

The zinc layer on galvanized steel is less than a millimeter thick, so even minor scratches can result in localized rust. Stainless won't rust no matter how deep the scratch.

Cost

Galvanized steel used in building construction.

Galvanized steel is far cheaper than even the most inexpensive stainless steels. Galvanized can drastically decrease the cost of structures that use very thick steel components, like buildings and machine housings.

About the Author

Richard Rowe has been writing professionally since 2007, specializing in automotive topics. He has worked as a tractor-trailer driver and mechanic, a rigger at a fire engine factory and as a race-car driver and builder. Rowe studied engineering, philosophy and American literature at Central Florida Community College.

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