Carbon has a dual effect in hardenable alloy steels. It both controls maximum obtainable hardness and contributes substantially to hardenability. It is the least expensive approach to improving hardenability.

Plain carbon steels do not have any other commonly used intentional alloy additions. They are generally used for less-critical applications in non-corrosive environments, and are not usually heat treated. Except for spring and bearing steels, more than .60 percent C is seldom used in steels for machined parts.

Steel grade designation:  10XX, 11XX,15XX

Click the links below to view
Chemical Composition Ranges
and Limits Charts.