Carbon Steels

When maximum content of the main elements do not exceed the following:

• Mn ? 1.65%

• Si ? 0.60%

• C < 0.60%

May be used with or without final heat treatment. May be annealed, normalized, case hardened or quenched and tempered. May be killed ^[a], semikilled, capped, or rimmed, and, when necessary, the method of deoxidation may be specified.

Alloy Steels

The maximum range of elements exceed the above amounts. Steels containing up to 3.99 % Cr, and smaller amounts (generally 1 4%) of other alloying elements.

Alloys steels are always killed, but special deoxidation or melting practices, including vacuum, may be specified for special critical applications.

Stainless Steels

Generally contains at least 10% Cr, with or without other elements. Few contain more than 30% Cr or less than 50% Fe. In the U.S. the stainless steel classification includes those steels containing 4% Cr.

In the broadest sense, this category can be divided into three groups based on structure: austenitic-(400 Series) nonmagnetic in the annealed condition. Nonhardenable; can be hardened by cold working. The general-purpose grade is widely known as 18-8 (Cr-Ni). ferritic-(400 Series) always magnetic and contain Cr but no Ni. Basic grade contains 17% Cr. This group also contains a 12% Cr steel with other elements, such as Al or Ti, added to prevent hardening. martensitic-(300 Series) Magnetic and can be hardened by quenching and tempering. Basic grade contains 12% Cr. This series contains more...