17-4PH Stainless Steel

17-4PH stainless steel stockholders and suppliers, delivering to the whole of the UK. West Yorkshire Steel are suppliers of 17-4PH stainless steel round bar and flat bar. 17-4PH is a corrosion resistant grade which is soft and ductile in the solution annealed condition. Medium to high strength, good toughness and strength is obtained by the appropriate ageing treatment. As a martensitic precipitation hardening stainless it is characterised by high tensile strength and high yield strength obtained by solution annealing, followed by a single or double low temperature age hardening treatment. 17-4PH has corrosive properties comparable to 304 austenitic stainless steel in many environments.

We welcome export enquiries for stainless steel. Contact our sales office and consult our shipping policy for further details.

Related Specifications

EN/DIN1.4542 X5CrNiCuNb16.4 AFNOR Z6CNU17-O4
ASTM-A564 Grade 630 UNS S17400 JIS SUS630
AMS 5643 5604 EN10088-3 H900 H1025 H1075 H1150D

Alternative stainless grades we supply

FV520B | S31254 | 904L | 310 | 321 | 316 | 440B | 440C | 420 | 410 | 416 | 431 | S31803 | S32760

Form of Supply

17-4PH is commonly stocked in round bar in the following conditions:-
17-4PH Condition A
17-4PH H900
17-4PH H1025
17-4PH H1075
17-4PH H1150x2

Flat bar is stocked in Condition A and can be cut to your specific requirements. We can also offer precision ground bar whcih can be produced and supplied ground to your required tolerances.

Contact our experienced sales team who will assist you with your 17-4PH stainless steel enquiry.

  • Flat
  • Diameter

Click on the headings below for further information


Commonly used in industries such as offshore, marine, food, paper mills, oil field and aerospace. 17-4PH is used for components such as fasteners, couplings, screws, bushings, studs, fittings, valve stems, roller, wear rings.

Carbon0.07% maxChromium15.00-17.50%
Manganese1.00% maxNickel3.00-5.00%
Silicon1.00% maxCopper3.00-5.00%
Phosphorous0.04% maxNiobium +0.15-0.45%
Sulphur0.03% maxTantalum

Heat slowly and uniformly to 1180-1200ºC. Do not forge below 1010ºC. Hold at temperature for one hour prior to forging the component. Cool in air to room temperature. Forged components require solution annealing before any further heat treatment.

17-4PH stainless has very good corrosion resistance properties. Corrosion tests in service have shown good results in all aged conditions. With better corrosion resistance to standard hardenable stainless grades such as 431, 420 and 410. 17-4PH has corrosion resistance comparable to 304 stainless specification.

17-4PH requires similar arc and resistance welding processes to those used on standard specifications of stainless steel. Welding up to 100mm thick can be carried out without the requirement of pre heating due to its low hardness. We recommend you contact your welding consumables supplier who should provide you full assistance and information on welding 17-4PH stainless steel.

Similar in machining characteristics to 304 and 410 stainless steel specifications. Condition H900 has high hardness and strength which is the most difficult to machine and the machining of this is recommended to be carried out at 60% of the rate which is used for Condition A.

For increase resistance to surface wear, with a slight reduction in corrosion resistance, 17-4PH can be nitrided. When nitrided at 540ºC an approximate hardness of 64-67 HRc is achievable, with a surface hardness depth of up to 0.15mm. The steel maintains a high core strength.

17-4PH is commonly supplied in the solution treated condition (Condition A). Heat treated at different temperatures will offer a wide range of properties. (We also hold stock in H1150+H1150).

ConditionTemp. [°C]Hardness
Time (hours)
Type of
A10381/2Oil/Air (to below 32°C)363 max39 max
H1150+H1150621-6214 followed by 4Air/Air277-31128-33

Tensile Strength N/mm²1034138013101170114010351000965860
0.2% YS N/mm²6501275120011401035930860760585
Reduction of Area %30-605054565858606068
Elongation %6-151414151617192022
Charpy Impact J>203447616168108135


Heat treatment temperatures, including rate of heating, cooling and soaking times will vary due to factors such as the shape and size of each 17-4 PH steel component. Other considerations during the heat treatment process include the type of furnace, quenching medium and work piece transfer facilities. Please consult your heat treatment provider for full guidance on heat treatment of 17-4PH stainless steel.

Stainless steel grade 17-4 PH is available with BS EN 10204 3.1 mill certificate, please request when placing any orders.

17-4 PH stainless is supplied in accordance with our ISO 9001:2015 registration.