- Aircraft structural components, motor shafts, valve stems, gears and fittings in aerospace
- Oil and gas equipment operating under sustained load in corrosive environments
- Pump components and impellers in chemical processing
- Turbine and power generation components requiring strength at elevated temperature
- Precision engineering parts across motorsport and defence
- Applications where corrosion resistance and high strength must be achieved without the weight penalty of alloy steel
17-4PH Stainless Steel
Typical Applications
Motor Shafts
Aircraft Structural Parts
Valve Stems
Gears
AMS 5643, AMS 5604, AMS 5622 Suppliers & Stockists
Dynamic Metals is a specialist supplier and stockholder of 17-4 PH stainless steel, supplying aerospace and motorsport industries with certified material to AMS 5643, AMS 5604 and AMS 5622. No Minimum order quantities.
17-4 PH is the most widely used precipitation hardening stainless steel in the world. Its combination of high strength, good corrosion resistance and straightforward heat treatment makes it the default choice across an exceptionally broad range of industries — from aerospace structural components and motor shafts to valve stems, gears and oil and gas equipment.
Mechanical properties are developed through precipitation heat treatment, with tensile strength ranging from 931 MPa in the H1150 condition through to 1310 MPa at H900. Six discrete ageing conditions allow engineers to select the precise balance of strength and ductility required — a flexibility that few other stainless grades can offer. Properties are retained at operating temperatures up to 316°C (600°F), making the alloy suitable for elevated temperature service across turbine, valve and power generation applications.
Three specifications govern supply of 17-4 PH from Dynamic Metals. AMS 5643 covers bars, wire, forgings, mechanical tubing and flash-welded rings in the standard grade. AMS 5622 covers the same product forms but to a higher premium aircraft-quality standard, requiring consumable electrode remelting. AMS 5604 covers sheet, strip and plate up to 4 inches (102 mm) nominal thickness. All material is supplied in the solution heat-treated condition, ready for customer age hardening to the required H-condition. Full material certification and traceability to the original melt heat is provided with every shipment.
Related Products
Key Features and Benefits
• Tensile strength from 931 MPa (H1150) to 1310 MPa (H900) — six selectable ageing conditions to balance strength and toughness for each application
• Three specifications available — AMS 5643 (standard bar/forgings), AMS 5622 (premium aircraft-quality bar/forgings, consumable electrode remelted) and AMS 5604 (sheet, strip and plate)
• Good corrosion resistance across all heat treatment conditions, without requiring protective surface coating in most applications
• Copper addition (3.00–5.00%) combined with niobium stabilisation delivers consistent, predictable heat treatment response
• Weldable — AMS 5604 is specifically noted for applications where welding during fabrication is required. Machines and forms readily in the solution annealed condition, before age hardening to final properties
Technical specification
Related Specifications
AMS 5604
AMS 5622
AMS 5643
UNS S17400
W.Nr 1.4548
Specific Gravity
7.74 g/cm3
Chemical Composition (WT %)
Min
Max
C
-
0.07
Si
-
1.00
Mn
-
1.00
P
-
0.040
S
-
0.030
Cr
15.00
17.50
Mo
-
0.50
Ni
3.00
5.00
Cb
5 x %C
0.45
Cu
3.00
5.00
Fe
Bal
-
Typical Mechanical Properties in the Annealed Condition
H900
H925
H1025
H1075
H1100
H1150
0.2% Proof Stress
MPA
Min
-
1172
1069
1000
862
793
724
Tensile Strength
MPA
Min
-
1310
1172
1069
1000
965
931
Elongation
%
Min
L
10
10
12
13
14
16
Reduction of area
%
Min
L
40
44
45
45
45
50
Hardness
HBW
Min
-
388
375
331
311
302
277
Hardness
HB
Max
-
444
429
401
375
363
352
- Six precipitation hardening conditions — H900 through H1150 — give engineers direct control over the balance of strength and ductility
- Tensile strength ranges from 1310 MPa (H900) down to 931 MPa (H1150)
- 0.2% proof stress from 1172 MPa (H900) down to 724 MPa (H1150)
- Longitudinal elongation ranges from 10% minimum (H900) to 16% minimum (H1150)
- Hardness ranges from 388–444 HBW (H900) down to 277–352 HBW (H1150) — useful for condition verification without destructive testing
- Properties maintained at service temperatures up to 316°C (600°F)
- Where stress corrosion cracking is a concern, AMS 5622 and AMS 5643 recommend ageing at no lower than H1025
- Chromium content (15.00–17.50%) forms a stable passive oxide layer resisting atmospheric and mild chemical corrosion across all heat treatment conditions
- Copper addition within the composition contributes to passive film stability beyond what chromium alone would provide in mildly aggressive environments
- Performs reliably in aerospace structural applications, marine coastal environments, chemical processing media and oil and gas service
- Does not require additional protective coating in most applications
- Where stress corrosion cracking risk exists, ageing at H1025 or higher is recommended per ARP1110
- AMS 5643 — standard corrosion-resistant specification covering bars, wire, forgings, mechanical tubing and rings
- AMS 5622 — premium aircraft-quality version of the same product forms, requiring consumable electrode remelting (VAR or ESR)
- Remelting required by AMS 5622 eliminates non-metallic inclusions that would reduce toughness and fatigue performance
- AMS 5622 is the specification of choice for safety-critical aerospace components
- AMS 5604 covers sheet, strip and plate with the same chemical composition but tailored testing requirements for flat-rolled product forms
- Every heat subject to chemical analysis and macrostructure examination, with tensile properties certified after precipitation heat treatment
- Machine in solution annealed condition before age hardening to the required H-condition
- Lower work hardening rate than austenitic stainless steels — more predictable machining behaviour
- Copper addition aids chip formation — more practical to machine at scale than many comparable high-strength grades
- Minimal dimensional change during ageing — components can be machined close to final dimensions before heat treatment without significant distortion risk
- Weldable using standard TIG and MIG processes with appropriate filler selection — AMS 5604 specifically covers applications where welding during fabrication is required
- Post-weld re-solution treatment and re-ageing recommended for joints requiring full mechanical properties
- Applicable ageing conditions and temperatures defined within AMS 5643, AMS 5622 and AMS 5604
- Bar, wire, forgings and mechanical tubing — AMS 5643 (standard) and AMS 5622 (premium aircraft-quality with consumable electrode remelting)
- Sheet, strip and plate up to 4 inches (102mm) nominal thickness — AMS 5604
- All material supplied in solution heat-treated condition, ready for customer age hardening to required H-condition
- No minimum order quantities on stock items
- Suitable for both prototype development projects and full production contracts
- The benchmark precipitation hardening stainless steel — six-condition ageing system gives flexibility that solid solution strengthened grades cannot match
- Single stock material can be processed to meet a broad range of application requirements
- Tensile strength up to 1310 MPa with good corrosion resistance eliminates need for protective coating in most structural applications — reducing manufacturing complexity and long-term maintenance cost
- Ready availability in bar, forgings, sheet and plate covers most component geometries without difficulty
- Wide OEM aerospace approval and long track record in oil and gas, power generation and precision engineering reduces qualification risk for new programmes
- Specialist supplier of 17-4 PH to aerospace, motorsport and industrial customers since 1997
- Certified stock held to AMS 5643, AMS 5622 and AMS 5604 with full material certification and traceability to original melt heat
- Consumable electrode remelting route confirmed on certification where AMS 5622 is specified
- Team available to advise on specification selection, condition choice and heat treatment requirements
- No minimum order quantities — supports both development programmes and production contracts
- AS9100 certified
- Fast UK delivery on standard stock sizes
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