Steel
Stainless steel is a name given to a group of steel alloys with many differences in properties and behaviour having one property in common - resistance to corrosion.
When an Alloy of Steel contains more than approximately 10.5% Chromium it can be classed as a stainless steel. This is due to the fact that Chromium has a high affinity for oxygen and forms a tenacious, stable oxide film, which is resistant to further chemical or physical change. This film, known as the passive film, forms practically instantaneously in ordinary atmospheres and has the remarkable property of being self-healing and rebuilding when it has been removed.
The large group of stainless steels can be divided into two major groups, namely Austenitic and Ferritic. The Ferritic group can be split again into two groups, Martensitic and Ferritic. If you would like to know more about the different types of steels within these groups, please follow one of the links below.