Effect on Properties and Cost
Stainless steel is iron alloyed to chromium with certain additional elements to give the required properties to the finished metal. Since many of these alloying elements are expensive, producers try to minimize cost by closely controlling the percentages of these alloying elements while maintaining the desired properties. Listed below is a summary of the effects of various alloying elements in steel.
Carbon
Carbon, in most situations, is an impurity in stainless steel, which is removed in the steelmaking process. It can impair corrosion resistance. Its presence, however, raises strength especially at elevated temperatures.
Manganese
Manganese is added to stainless steel to improve hot working properties. Manganese has been used as a substitute for nickel in the 200 series stainless steels (e.g., type 201 as a substitute for Type 304) to reduce cost.
Chromium
Stainless steel by definition has a minimum chromium content of 10.5%. This concentration of chromium provides stainless steel with its inherent corrosion resistance and particularly oxidation resistance. This resistance increases as more chromium is added to the stainless steel.
