WHAT CAN CAUSE STAINLESS STEEL TO RUST?

There are more than 150 grades of stainless steel out there, and some are simply more prone to rust than others. It`s important to consider that, although 304 stainless steel can corrode, it will not rust in normal atmospheric conditions. The corrosion of stainless steel only occurs under more aggressive environments or in situations where the composition of the steel contains impurities.

Though stainless steel, for the most part, is resistant in nearly every environment, the various types will react differently when put into hostile conditions that aid in corrosion.

Some common causes of stainless steel corrosion include:

Bimetallic Corrosion – Dissimilar metals coming with a common electrolyte coming into contact with each other (also referred to as galvanic corrosion)

Crevice Corrosion – Triggered when oxygen levels in a crevice are very low

General Corrosion – Triggered when stainless steel has a pH value of >1

Intergranular Corrosion – When you heat stainless steel in the range of 450 to 850 degrees Celsius, carbon in the steel will convert to grain boundaries which lead to corrosion

Pitting Corrosion – When stainless steel is exposed to environments that contain chlorides (such as seawater)

Stainless steel is a multifunctional metal that can be used successfully for a huge range of applications, from automotive to medical devices. It`s the most readily available grade of stainless steel and typically less expensive than its common counterpart, 316 stainless steel, which offers super corrosion resistance but is very similar overall. If your application isn`t exposed to aggressive chemicals and is instead only exposed to milder acids, then 304 stainless steel is likely the perfect fit.