17 4 PH

17/4PH / S17400 stainless steel is a 17% chromium, 4% nickel precipitation hardening stainless steel. Classed as a martensitic grade it obtains a variety of strength and hardness properties from a relatively simple set of heat treatment processes.

This strength and toughness coupled with the high corrosion resistance and ease of fabrication has made 17/4PH a popular choice across a wide range of industries. Usually stocked in the solution annealed condition (Condition A) higher strength levels are obtained by a single or double heat treatment.

Nominal Composition

Iron	Rem
Chromium	17.0%
Nickel	4.0% max
Copper	4.0% max
Niobium and Tantalum	0.30%

Related Specifications

Type 630	UNS S17400
DIN 1.4542	ASME SA564

Key Features

High strength and Hardness
Excellent corrosion resistance
Good welding properties

Typical Physical Properties

Density	7.81gm/cm³
Melting Point	1440?C
Specific Heat	460 j/kg ?K
Electrical Resistivity	0.77 microhm-m
Thermal Conductivity	17.8 W/m ?K
Modulus of Elasticity (H900 condition)	200 GPa
Coefficient of Thermal Expansion	10.8 x 10^-6

Fabrication Properties

Hot Workability	Good
Cold Workability	Fair (in the annealed condition)
Hot working temperature	1010-1230°C
Stress Relieving Temperature	350-430°C
Machinability	Okay
Welding	Good (post weld heat treatment may be needed)

Typical Applications
17/4PH has been used for aircraft and jet engine parts, gears and bushes, mixing screws, actuators, nuclear reactor components chemical process plant fasteners and couplings, oilfield valve stems, pump shafts, undercarriage components.

This technical information is given by John Hood & Co.without charge and the user shall employ such information at their own discretion and risk. For more detailed technical advice on temper selection, fabrication, joining, machining, physical and mechanical data please contact us as space does not permit the listing of every feature of the material.