Type 17-4

• Chromium-nickel grade of Stainless Steel
• Hardened by a single low-temperature precipitation-hardening treatment which provides excellent mechanical properties at a high strength level
• Should not be used in the solution treated condition

Available Forms

Type 17-4 stainless steel is available in:

• Bar
• Wire

Specifications

Type 17-4 is covered by the following specifications:

• AMS 5643
• ASTM A 564 Type 630

Typical Applications

• Used in a wide variety of applications because of its unique combination of advantages
• Applications include boatshafts, pump shafts, valve gates, plugs, seats, stems and trim, springs, gears, fasteners, chains, mixing equipment, aerospace, applications such as hydraulic actuators, structural components, fasteners, connectors in high pressure systems; cutter blades; racing car parts; and oil field equipment

Machinability

This grade has a machinability rating of 48% in the annealed condition (Condition A), with surface cutting speed of 80 feet per minute. In the overaged condition (H 1150-M), the machinability rating is 76% with surface cutting speed of 125 feet per minute.

Weldability

Readily weldable by all the commerical processes. Preheating and post-heating practices used for the standard hardenable stainless grades are not required.

Corrosion Resistance

The corrosion resistance of 17-4 is superior to that of hardenable straight chromium grades such as T410.  It approaches the corrosion resistance of the chromium nickel grades.  In many corrosive media it is equal to such grades as Type 302.  Corrosion resisting properties will be affected by such conditions as surface finish and aging heat treatment.

Forging

Forge between 2050 and 2150° F. Do not forge below 1850° F. Forgings are air cooled to 90° F or lower.  Large or intricate forgings should be equalized at some temperature between 1900° F and the forging temperature before air-cooling.