This specification covers hot-finished or cold-finished bars, except bars for forging, suitable for machining processes. It includes rounds, squares, and hexagons in the more commonly used types of stainless free-machining steels designed especially for optimum machinability and for general corrosion and high-temperature service. Bars may be furnished either hot finished or cold finished in one of the conditions specified. Materials shall adhere to specified chemical composition requirements. At least one hardness testing shall be made midway between surface and center on each lot to determine that the material conforms to hardness requirements. Also, test methods and definition for hardness testing are presented.

1.1 This specification covers hot-finished or cold-finished bars, except bars for forging (Note 1), suitable for machining processes. It includes rounds, squares, and hexagons in the more commonly used types of stainless free-machining steels designed especially for optimum machinability and for general corrosion and high-temperature service. Stainless steel bars other than the free-machining types are covered in a separate specification (Note 2).

1.2 This specification is expressed in both inch-pound units and in SI units; however, unless the purchase order or contract specifies the applicable M specification designation (SI units), the inch-pound units shall apply. The values stated in either inch-pound units or SI (metric) units are to be regarded separately as standard: within the text and tables, the SI units are shown in [brackets]. The values stated in each system may not be exact equivalents: therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.