17-4PH Stainless Steel Bar AMS 5643 / AMS 5622
Short Description:
17-4PH Stainless Steel Bar (AMS 5643 / AMS 5622)
Precipitation hardening stainless steel with high strength and good corrosion resistance.
Available in round bar, flat bar, square bar, hex bar and forged bar.
Suitable for aerospace, shafts, valves, fasteners and precision machined parts.
17-4PH Stainless Steel Bar (AMS 5643 / AMS 5622)
17-4PH Stainless Steel Bar is a precipitation-hardening martensitic stainless steel bar
known for its excellent combination of high strength, good corrosion resistance, and reliable dimensional stability.
It is widely used in aerospace, energy, petrochemical, marine, valve, shaft, fastener, and precision engineering applications.
Under international material systems, 17-4PH is commonly identified as UNS S17400,
Grade 630, 1.4542, and X5CrNiCuNb16-4.
For customers requiring aerospace-grade supply, AMS 5643 and AMS 5622
are two frequently referenced standards for bar products.
Product Introduction
17-4PH stainless steel bar offers a practical solution for applications where conventional stainless steels
do not provide enough strength, while ordinary alloy steels cannot deliver the required corrosion resistance.
One of its main advantages is that it can be supplied in the solution-treated condition and then strengthened
through aging heat treatment, allowing manufacturers to achieve high mechanical properties with relatively low distortion.
Compared with common austenitic stainless steels such as 304 or 316, 17-4PH provides much higher yield and tensile strength.
At the same time, it maintains good resistance to many industrial and mildly corrosive environments, making it a popular material
for demanding structural and mechanical components.
Key Features of 17-4PH Stainless Steel Bar
- High tensile strength and yield strength after aging treatment
- Good corrosion resistance for industrial and marine-related service environments
- Good machinability in solution-treated condition
- Excellent dimensional stability during heat treatment
- Suitable for precision shafts, valve parts, fasteners, fittings, and aerospace components
- Available in multiple aging conditions such as H900, H925, H1025, H1075, H1100, and H1150
Product Specifications
| Item | Description |
|---|---|
| Product Name | 17-4PH Stainless Steel Bar |
| Material Grade | 17-4PH / UNS S17400 / Grade 630 / 1.4542 |
| Standards | AMS 5643, AMS 5622, ASTM A564, ASME SA564 |
| Forms | Round Bar, Flat Bar, Square Bar, Hex Bar, Forged Bar |
| Surface Finish | Black, Peeled, Rough Turned, Bright, Polished, Centerless Ground |
| Diameter Range | 6 mm to 350 mm |
| Length | 1000 mm to 6000 mm or as required |
| Heat Treatment | Solution Treated / Condition A / Aged Condition |
| Certification | EN 10204 3.1 / Mill Test Certificate / PMI / UT on request |
| Origin | China |
Chemical Composition of 17-4PH Stainless Steel Bar
| Element | Content (%) |
|---|---|
| Carbon (C) | Max 0.07 |
| Manganese (Mn) | Max 1.00 |
| Silicon (Si) | Max 1.00 |
| Phosphorus (P) | Max 0.040 |
| Sulfur (S) | Max 0.030 |
| Chromium (Cr) | 15.00 – 17.50 |
| Nickel (Ni) | 3.00 – 5.00 |
| Copper (Cu) | 3.00 – 5.00 |
| Niobium + Tantalum (Nb+Ta) | 0.15 – 0.45 |
Mechanical Properties of 17-4PH Stainless Steel Bar
| Condition | Tensile Strength | Yield Strength | Elongation | Hardness |
|---|---|---|---|---|
| H900 | Min 1310 MPa | Min 1170 MPa | Min 10% | Approx. HRC 40 – 47 |
| H925 | Min 1170 MPa | Min 1070 MPa | Min 10% | Approx. HRC 38 – 44 |
| H1025 | Min 1070 MPa | Min 1000 MPa | Min 12% | Approx. HRC 35 – 40 |
| H1075 | Min 1000 MPa | Min 860 MPa | Min 13% | Approx. HRC 32 – 38 |
| H1100 | Min 965 MPa | Min 795 MPa | Min 14% | Approx. HRC 30 – 36 |
| H1150 | Min 930 MPa | Min 725 MPa | Min 16% | Approx. HRC 28 – 37 |
AMS 5643 vs AMS 5622 Comparison
Both AMS 5643 and AMS 5622 refer to 17-4PH stainless steel products,
but they are not positioned exactly the same in practice.
| Item | AMS 5643 | AMS 5622 |
|---|---|---|
| Material Type | 17-4PH Stainless Steel | 17-4PH Stainless Steel |
| UNS | S17400 | S17400 |
| Main Supply Form | Bar, Wire, Forgings, Tubing, Rings | Bar, Wire, Forgings, Tubing, Rings |
| Melting Route | Standard aerospace supply route | Vacuum melt route such as VAR / CEVM |
| Typical Application Level | General aerospace and industrial use | Higher reliability and more critical applications |
| Material Cleanliness | Standard controlled quality | Higher metallurgical cleanliness requirement |
In simple terms, AMS 5643 is commonly selected for mainstream aerospace and industrial bar applications,
while AMS 5622 is usually chosen when customers require a vacuum-melt quality route
for more critical service conditions.
Equivalent Grades and International Designations
| System | Designation |
|---|---|
| UNS | S17400 |
| ASTM / ASME | ASTM A564 / ASME SA564 Grade 630 |
| AISI | 630 |
| EN | 1.4542 |
| DIN / EN Name | X5CrNiCuNb16-4 |
| AMS | AMS 5643 / AMS 5622 |
Typical Applications
- Aerospace shafts, fittings, and structural components
- Valve stems, pump shafts, and mechanical seal components
- Oil and gas tools and high-strength fasteners
- Marine hardware and offshore equipment parts
- Chemical processing and petrochemical machinery
- Paper, food processing, and industrial precision parts
Available Sizes and Supply Condition
We can supply 17-4PH stainless steel bar in a wide range of sizes and conditions according to customer drawings,
machining requirements, and final application demands.
| Bar Type | Common Size Range | Supply Condition |
|---|---|---|
| Round Bar | 6 mm – 350 mm | Solution Treated / Aged |
| Flat Bar | Thickness 6 mm – 80 mm | Hot Rolled / Forged / Machined |
| Square Bar | 8 mm – 100 mm | Hot Rolled / Forged |
| Hex Bar | 8 mm – 65 mm | Bright Drawn / Machined |
| Forged Bar | Customized | Forged + UT + Rough Machined |
Inspection and Quality Control
To ensure reliable performance and traceability, 17-4PH stainless steel bar can be supplied with full inspection documents
and additional testing according to project requirements.
- Mill Test Certificate EN 10204 3.1
- Positive Material Identification (PMI)
- Ultrasonic Testing (UT)
- Hardness Testing
- Dimension Inspection
- Surface Quality Inspection
Packing of 17-4PH Stainless Steel Bar
Standard export packing is designed to protect the bars from rust, surface damage, and transportation impact during long-distance shipment.
Bundles, wooden cases, waterproof wrapping, and end protection can be arranged according to size and shipping method.
Why Choose Our 17-4PH Stainless Steel Bar
- Stable raw material sourcing and controlled production process
- Support for AMS, ASTM, and customer-specific technical requirements
- Available for aerospace, industrial, and precision machining applications
- Flexible supply in forged, hot rolled, bright, and machined condition
- Fast response for quotation, stock inquiry, and technical confirmation
FAQ
What is 17-4PH stainless steel bar used for?
17-4PH stainless steel bar is widely used for shafts, valves, fasteners, fittings, aerospace parts, marine hardware,
and other components requiring both high strength and corrosion resistance.
What is the difference between AMS 5643 and AMS 5622?
AMS 5643 is a mainstream aerospace specification for 17-4PH products, while AMS 5622 generally refers to vacuum-melt
material with higher metallurgical cleanliness for more critical applications.
Is 17-4PH stronger than 316 stainless steel?
Yes. 17-4PH offers significantly higher strength than 316 stainless steel, especially after aging heat treatment.
It is often selected when 316 does not provide enough mechanical performance.
Can 17-4PH stainless steel bar be machined?
Yes. It is commonly machined in solution-treated condition and then aged to achieve the required final hardness and strength.
What forms of 17-4PH bar can you supply?
We can supply round bar, flat bar, square bar, hex bar, and forged bar according to customer requirements.
Can you provide MTC and UT reports?
Yes. EN 10204 3.1 certificate, PMI, UT, hardness test, and other inspection reports can be provided upon request.
