Materials · Stainless steels
17-4PH stainless steel fasteners
Bolts, studs, nuts and machined parts in 17-4PH (17/4PH, AISI 630), made to your drawing from certified, traceable bar. A precipitation hardening stainless steel combining high strength, toughness and good corrosion resistance; we make 17-4PH fasteners to order.
AISI 630
Also ASTM A564 type 630
3 to 5% Cu
Copper for precipitation hardening
1 step
Single ageing treatment after solution annealing
1 to 500
Single prototypes to batches of several hundred
About the alloy
High strength stainless steel
HAGUE FASTENERS makes 17-4PH fasteners in the UK where a bolt or stud needs much higher strength than austenitic stainless steel can give. 17-4PH is one of the most widely used precipitation hardening stainless steels: soft and ductile in the solution annealed condition, and capable of high properties after a single ageing treatment.
The ageing temperature sets the balance of strength and toughness. Lower ageing temperatures give the highest strength, while higher ones such as H1150 trade some strength for toughness and resistance to stress corrosion cracking. It has good corrosion resistance and is magnetic. See all stainless steels.
At a glance
- Martensitic precipitation hardening stainless
- High strength with good toughness
- Good corrosion resistance
- Properties set by the ageing condition
- Magnetic
Chemical composition
17-4PH chemical composition
Weight %. Other elements: Nb + Ta 0.15 to 0.45.
| Element | Min % | Max % |
|---|---|---|
| C | – | 0.07 |
| Mn | – | 1.00 |
| Si | – | 1.00 |
| Cr | 15.00 | 17.50 |
| S | – | 0.03 |
| P | – | 0.04 |
| Fe | Bal. | – |
| Ni | 3.00 | 5.00 |
| Cu | 3.00 | 5.00 |
| Nb | 0.15 | 0.45 |
Heat treatment
17-4PH heat treatment conditions
Mechanical properties depend on the condition.
| Condition | Treatment |
|---|---|
| Condition A | Soak at 1900°F (1038°C) for 30 minutes and cool below 60°F (16°C) for complete martensite transformation. |
| Condition H900 | Treat Condition A material at 900°F (482°C) for 1 hour, air cool. |
| Conditions H925, H1025, H1075, H1100, H1150 | Soak solution treated material for 4 hours at the specified temperature, air cool. |
| Condition H1150M | Soak solution treated material at 1400°F (760°C) for 2 hours, air cool, then reheat to 1150°F (620°C) for 4 hours and air cool. |
These figures are for general information only and may change without notice. We believe them to be accurate, but HAGUE FASTENERS LIMITED gives no warranty and accepts no liability for their accuracy or completeness. Actual properties may vary, and nothing here guarantees the material for a particular use.
Applications
Where 17-4PH is used
17-4PH is used wherever a stainless fastener needs high strength: in oil and gas equipment, valves and pumps, aerospace fittings and general engineering.
- Oil and gas equipment
- Valve stems and pump shafts
- Aerospace fittings and fasteners
- High strength stainless bolting
Designations
Alternative designations and specifications
AISI 630 AMS 5604 AMS 5622 AMS 5643 ASTM A564 (630) ASTM A693 (630) ASTM A705 (630) MIL C-24111 MIL P-47183 MIL S-81591 UNS S17400. Trade names include Carpenter Custom 630, 17-4, AL 17-4, Marinox 1, CSM 21 and MAXX 17-4.
What we make
17-4PH fasteners and components
Made to your drawing or to the standard you specify.
Certification and testing
Certified, traceable and tested
17-4PH bar comes from approved UK, EU or US mills with heat traceability to release. We supply EN 10204 3.1 or 3.2 certificates, PMI where specified and independent UKAS-accredited testing. Heat treatment is by approved partners, with furnace charts on request. See quality and testing.
Questions
Frequently asked questions
What does 17-4PH mean?
17-4PH means about 17% chromium and 4% nickel, precipitation hardening. Copper additions allow the steel to be strengthened by a single ageing treatment.
Which 17-4PH condition is best for fasteners?
It depends on the duty. Lower temperature conditions give the highest strength, while H1150 and H1150M give more toughness and better resistance to stress corrosion cracking. Your specification normally sets the condition.
Are 17-4PH fasteners stronger than 316?
Yes, much stronger. 17-4PH fasteners are chosen where 316 lacks strength and a stainless steel is still wanted.
What is the equivalent of 17-4PH?
17-4PH is also known as AISI 630 and ASTM A564 type 630, and is supplied under trade names such as Carpenter Custom 630.
17-4PH enquiry?
Send us your drawing or specification
Tell us the grade, condition, sizes, quantity and paperwork you need.