This specification covers the standard for carbon steel, alloy steel, and martensitic stainless steel castings that are to be subjected to higher mechanical stresses. All castings shall undergo heat treatment either by full annealing, normalizing, normalizing and tempering, or quenching and tempering and shall be regulated under pyrometers. Several grades of steel castings are covered and shall conform to the required chemical composition for sulfur and phosphorus. A tension test shall be performed and shall conform to the required tensile strength, yield point, and elongation. The notch bar impact properties shall also be determined by testing one set of three Charpy V-notch impact specimens.

1.1 This specification covers carbon steel, alloy steel, and martensitic stainless steel castings that are to be subjected to higher mechanical stresses than those covered in Specification A 27/A 27M.

1.2 Several grades of steel castings are covered, having the chemical composition and mechanical properties prescribed in Tables 1 and 2.

1.3 The values stated in 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 are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.