Type 17 chrome - 7 nickel stainless steel wire (AISI 631) has the corrosion resistance of Type 302 plus superior strength and heat resistance. This grade of stainless wire possesses high elastic qualities similar to music wire while maintaining the corrosion resistant qualities of the standard Type 302 stainless. The alloy is an excellent material for all kinds of springs where long life is required under severe service conditions, providing excellent fatigue properties, ductility, high yield strength, modulus of elasticity, and strength-to-weight ratio.
17 chrome - 7 nickel offers the advantage of being easily formed in Condition C and then hardened to high strength levels by simple heat treatment. 17-7 is hardenable due to the addition of aluminum to the chemistry of the alloy.
Gibbs Interwire 17 chrome - 7 nickel stainless wire is furnished in the cold drawn Condition C and should be treated at 900ºF. for one hour after forming into springs to achieve the maximum tensile properties of Condition CH900 (cold drawn and age hardened). Sizes are available within the range 0.017" - 0.625" conforming ASTM A 313, AND AMS-5678.