This specification covers round, shaped and flat rolled plain carbon and alloy steel spring wires, uniform in quality and temper, intended for the manufacture of mechanical springs that can withstand moderate fatigue stresses over some relatively low number of cycles. This wire shall be either in the annealed and cold-drawn or oil-tempered conditions. The steel may be made by any commercially accepted steel making process in either ingot cast or strand cast form. The percentage of the following elements: carbon, manganese, phosphorus, sulfur, silicon, chromium, and vanadium, shall conform to the chemical composition requirements and be determined by heat analysis. Tensile and wrap tests shall conform to the mechanical requirements such as tensile strength. Metallurgical requirements including eddy current testing for etched surface, decarburization, and inclusion content are detailed.

1.1 This specification covers a quality of round and shaped plain carbon and alloy steel spring wire, uniform in quality and temper, intended for the manufacture of mechanical springs that can withstand moderate fatigue stresses over some relatively low number of cycles. The quality level is between the commercial quality grades of wire such as Specifications A 401/A 401M, A 231/A 231M, and A 229/A 229M and the valve spring quality grades such Specifications as A 230/A 230M, A 232/A 232M, A 877/A 877M and A 878/A 878M. It is similar to the grade TD (referenced in EN 10270-2) intended for medium fatigue levels, such as required for clutch springs. This wire shall be either in the annealed and cold-drawn or oil-tempered condition as specified by purchaser.

1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the inch-pound units are shown in parentheses. The values stated in each system are not exact equivalents; therefore, each system must be used independent of the other.