ABSTRACT
Stainless steels are alloys of iron and chromium usually with other added components. They are the most widely applied and versatile of the corrosion-resistant alloys formulated from the anodic passivating metals. The chapter argues that equilibria in multi-component stainless steels are approached by considering how successive additions of other components modify equilibria in the iron-chromium binary system. The American Iron and Steel Institute (AISI) specifications use a three-digit code to identify wrought stainless steels by structure. The first digit defines the following classes: austenitic steels with nickel as the primary austenite stabilizer; austenitic steels with manganese and nitrogen as nickel substitutes; and ferritic and martensitic steels with little or no nickel. The other digits identify the steels and letter suffixes indicate other features. Stainless steels resist or succumb to corrosion according to whether or not they succeed in maintaining a passive surface. The chapter also discusses resistance to dry oxidation and applications of cast stainless steels.
