This specification covers martensitic chromium stainless steel forgings, forged bars, and forging stock for high-temperature service. The mechanical properties are developed by suitable heat treatment, as indicated for each alloy. Steel materials shall be manufactured by melting and forging processes, and heat treatments, that shall consist of austenizing, quenching, tempering, and stress relieving. Stainless steels may then be furnished in one of the following hot-finished conditions: as forged without descaling; forged and descaled; rough turned or rough machined. Specimens shall conform to required chemical compositions. Forgings shall undergo tension, impact, stress rapture, and hardness tests, and should conform to mechanical properties prescribed for individual grades and classes. These mechanical properties are: tensile strength, yield strength, elongation, reduction of area, impact strength, and Brinell and Rockwell hardness.

1.1 This specification covers martensitic chromium stainless steel forgings, forged bar, and forging stock for high temperature service. The mechanical properties are developed by suitable heat treatment, as indicated for each alloy.

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 units are to be regarded separately as standard. Within the text, 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 standard.

1.3 Supplementary requirements of an optional nature are provided for use at the option of the purchaser. The supplementary requirements shall apply only when specified individually by the purchaser in the purchase order or contract.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.