Stainless Steel - Corrosion Resistance: Background

Although one of the main reasons why stainless steels are used is corrosion resistance, they do in fact suffer from certain types of corrosion in some environments and care must be taken to select a grade which will be suitable for the application. Corrosion can cause a variety of problems, depending on the applications:

· Perforation such as of tanks and pipes, which allows leakage of fluids or gases,

· Loss of strength where the cross section of structural members is reduced by corrosion, leading to a loss of strength of the structure and subsequent failure,

· Degradation of appearance, where corrosion products or pitting can detract from a decorative surface finish,

· Finally, corrosion can produce scale or rust which can contaminate the material being handled; this particularly applies in the case of food processing equipment.

Corrosion of stainless steels can be categorised as one of:

-General Corrosion

-Pitting Corrosion

-Crevice Corrosion

-Stress Corrosion Cracking

-Sulphide Stress Corrosion Cracking

-Intergranular Corrosion

-Galvanic Corrosion

-Contact Corrosion

Source: http://www.azom.com/details.asp?articleID=1177