This specification has been declared “NONCURRENT” by the Aerospace Materials Division, SAE, as of August 2009. It is recommended, therefore, that this specification not be specified for new designs. “NONCURRENT” refers to those specifications which have previously been widely used and which may be required for production or processing of existing designs in the future. The Aerospace Materials Division, however, does not recommend these specifications for future use in new designs.

This specification covers low-alloy steel springs made of annealed round wire heat treated after forming.

These springs have been used for valve springs, clutch springs, and other highly stressed springs on which a hardened case is required as assurance that surfaces will not be decarburized, but usage is not limited to such applications. Hardness of these springs is very high and use is recommended only after careful consideration.