Stainless 17-4 PH® (UNS S17400)


17-4 PH® is a martensitic precipitation hardening stainless steel offering high strength and hardness along with moderate corrosion resistance up to 600˚F. It has good fabrication characteristics and can be age hardened using a single heat treatment in the 900-1150˚F temperature range. This grade has been used for a variety of oil field and chemical process equipment, as well as fittings and fasteners.

Chemical Composition

Chemical Composition (wt%) limits as specified in ASTM A693 (Type 630)*

Element 17-4 PH
Carbon 0.07
Chromium 15.0-17.5
Nickel 3.0-5.0
Copper 3.0-5.0
Manganese 1.00
Silicon 1.00
Phosphorus 0.040
Sulfur 0.030
Columbium + Tantalum 0.15-0.45

*Maximum, unless range is indicated

Physical Properties

Physical properties for 17-4 PH stainless steel

Density, lb/in3 0.280
Modulus of Elasticity, psi 28.5 x 106
Coefficient of Thermal Expansion, 68-212˚F, /˚F 6.0 x 10-6
Thermal Conductivity, Btu/ft hr ˚F 10.6
Specific Heat, Btu/lb ˚F 0.11
Electrical Resistivity, Microhm-in 38.6

Mechanical Properties

Mechanical property requirements for solution treated product (Condition A) as specified in ASTM A693.

Property 17-4 PH
Yield Strength, min. (ksi) -
Tensile Strength, min. (ksi) -
Elongation, min. (%) -
Hardness, max. (HBW) 38


Typical standards for 17-4 PH stainless steel

ASTM A693 (listed as Grade 630)
AMS 5604