17-4PH | 1.4542 | SUS630 | X5CrNiCuNb16-4 | STS630
Supply Range & Tolerances
1. Round Bar
- Hot Rolled / Forged: Diameter Φ16mm – Φ500mm
- Forged: Diameter Φ50mm – Φ400mm (larger sizes available upon request)
- Length: 2000mm – 5800mm (customizable)
- Tolerances: Compliant with ASTM A564 or EN 10088‑3
- Surface conditions: Black skin, peeled, turned, or ground finish
Flat Bar / Plate
- Thickness: 10mm – 300mm ｜ Width: 200mm – 1000mm
- Length: 3000mm – 5800mm, or cut to your order (customizable)
- Surface Finish: Mill finish, grinded, polished, or 4-side cut / milled
3. Forgings / Custom Shapes
- Valve bodies, pump shafts, turbine blades, high‑strength fasteners, and complex geometries – all manufactured from your prints
- Full dimensional flexibility: thickness, width, length, and shape all tailored to batch order requirements
Keyspark Steel offers precision plate component machining, specializing in steel plate milling and precision hole finishing. Custom-made to your drawings.
We also provide our overseas customers with assembly services for various CNC machined parts.
Our team does rough and fine machining for all kinds of forging ring parts. We provided rough turning service like slewing bearing rings and gear rings to many European construction machinery partners. Keyspark Steel have strong custom ability and an engineer teams. We make products from your drawings and are very flexible.
Keyspark Steel also offers importing clients custom cold drawn steel round bars, steel square bars and hexagon steel bars in different sizes with cold drawing dies as supporting items. The material have tight tolerance, smooth surface and stable material performance. And also cold drawing dies as supporting items.
Material 17-4PH Equivalent
|
Standard System |
Country/Region |
Equivalent Grade |
Common Search Terms |
|---|---|---|---|
|
AISI / ASTM |
USA |
17‑4PH, UNS S17400, AISI 630 |
17‑4PH stainless steel, 17-4PH material, 17‑4PH steel, AISI 630, AISI 17‑4 PH |
|
DIN / EN |
Germany |
1.4542, X5CrNiCuNb16‑4 |
1.4542 steel, DIN 1.4542 |
|
JIS |
Japan |
SUS630 |
SUS630 steel, JIS SUS630 |
|
GB |
China |
0Cr17Ni4Cu4Nb |
0Cr17Ni4Cu4Nb steel |
|
BS |
UK |
630 |
630 stainless steel |
|
KS |
Korea |
STS630 |
STS630 steel |
|
AFNOR |
France |
Z6CNU17‑04 |
Z6CNU17‑04 steel |
17-4PH Composition
|
Standard |
C |
Si |
Mn |
P |
S |
Cr |
Ni |
Cu |
Mo |
|---|---|---|---|---|---|---|---|---|---|
|
SAE AMS 5643Q-2003 |
≤0.07 |
≤1.00 |
≤1.00 |
≤0.040 |
≤0.030 |
15.00–17.50 |
3.00–5.00 |
3.00–5.00 |
≤0.50 |
The copper and niobium additions are essential for the precipitation‑hardening reaction. Chromium provides corrosion resistance, while nickel stabilizes the martensitic structure. Composition can be micro‑adjusted per batch order.
17-4PH Stainless Steel Properties
|
MECHANICAL PROPERTY |
METRIC VALUE |
IMPERIAL VALUE |
|---|---|---|
|
Hardness (Annealed / Condition A) |
≤ 363 HB / ≤ 38 HRC |
≤ 363 HB / ≤ 38 HRC |
|
Hardness (H900) |
375 – 444 HB / 40 – 47 HRC |
375 – 444 HB / 40 – 47 HRC |
|
Hardness (H1025) |
331 – 375 HB / 34 – 42 HRC |
331 – 375 HB / 34 – 42 HRC |
|
Hardness (H1150) |
277 – 311 HB / 28 – 37 HRC |
277 – 311 HB / 28 – 37 HRC |
|
Tensile Strength (σb, Condition A) |
≥ 1000 – 1100 MPa |
≥ 145 – 160 ksi |
|
Tensile Strength (σb, H900) |
≥ 1310 MPa |
≥ 1310 MPa |
|
Tensile Strength (σb, H1025) |
≥ 1069 MPa |
≥ 155 ksi |
|
Tensile Strength (σb, H1150) |
≥ 931 MPa |
≥ 135 ksi |
|
Yield Strength (σ0.2, Condition A) |
≥ 380 MPa |
≥ 55 ksi |
|
Yield Strength (σ0.2, H900) |
≥ 1172 MPa |
≥ 170 ksi |
|
Yield Strength (σ0.2, H1025) |
≥ 1000 MPa |
≥ 145 ksi |
|
Yield Strength (σ0.2, H1150) |
≥ 724 MPa |
≥ 105 ksi |
|
Elongation (δ5, Condition A) |
≥ 35 % |
≥ 35 % |
|
Elongation (δ5, H900) |
≥ 10 % |
≥ 10 % |
|
Elongation (δ5, H1025) |
≥ 12 % |
≥ 12 % |
|
Elongation (δ5, H1150) |
≥ 16 % |
≥ 16 % |
|
Reduction of Area (ψ, Condition A) |
≥ 55 % |
≥ 55 % |
|
Reduction of Area (ψ, H900) |
≥ 40 % |
≥ 40 % |
|
Reduction of Area (ψ, H1025) |
≥ 45 % |
≥ 45 % |
|
Reduction of Area (ψ, H1150) |
≥ 50 % |
≥ 50 % |
|
Impact Toughness (KV, 20°C, Longitudinal) |
7 – 86 J |
5.6 – 63 ft·lb |
17-4PH steel is typically supplied in the solution-annealed Condition A, which is soft and formable, and subsequently aged to develop the desired strength. The aging temperature (condition code H900 to H1150) determines the final property balance — lower temperatures give higher strength and hardness but lower ductility and impact toughness, while higher temperatures trade strength for improved ductility and toughness. The properties above are minimum values from AMS 5643 (bar) and AMS 5604 (sheet/plate), with impact toughness ranges reflecting typical values across different aging conditions. Unit conversions: 1 MPa ≈ 0.145 ksi; 1 J ≈ 0.737562 ft·lb.
Delivery Condition of 17-4PH
Black Surface, Bright Surface, Turned Surface, Grinded Surface, Poblished surface.
17-4PH Material Application
Aerospace: Landing gear components, engine mounts, actuators, high‑strength fasteners, turbine blades.
Oil & Gas: Valve stems, pump shafts, drill collars, wellhead components, subsea hardware.
Chemical Processing: Reactor vessels, agitators, pumps, valves, heat exchangers.
Medical: Surgical instruments, orthopedic implants, dental tools, biopsy needles.
Nuclear: Control rod drive mechanisms, reactor internals, waste storage containers.
Industrial: High‑strength gears, shafts, springs, fasteners, moulds for plastics.
Marine: Propeller shafts, pump impellers, fittings for seawater service.
Food Processing: Equipment requiring both strength and corrosion resistance.
17-4PH Heat Treatment & Processing
Solution Annealing (Condition A): Heat AISI 17-4PH to 1,040°C ± 15°C, hold for 30 minutes per 25 mm of section thickness, then cool rapidly in air, oil, or water. Resulting hardness: approximately 363 HB maximum. This condition is optimal for machining.
Aging (Precipitation Hardening): After solution annealing and machining, age at 480–620°C for 1–4 hours, then air cool. The aging temperature determines the final strength and hardness. Common aging cycles:
H900: 480°C for 1 hour, air cool – highest strength (40‑44 HRC)
H1025: 550°C for 4 hours, air cool – good balance (34‑38 HRC)
H1150: 620°C for 4 hours, air cool – best toughness (28‑32 HRC)
Stress Relieving: Not typically required, but can be performed at 550–600°C before aging if necessary.
Pickling & Passivation: Recommended after heat treatment to restore corrosion resistance.
Processing Guide:
Machining: Solution‑annealed 17‑4PH steel (condition A) has good machinability, similar to 304 stainless steel. Carbide tools are recommended. Aged material is significantly harder and may require grinding.
Welding: 17‑4PH steel is readily weldable in the solution‑annealed condition using TIG, MIG, or electron beam welding. Post‑weld aging is recommended to restore properties in the heat‑affected zone.
Forging: Heat uniformly to 1,150–1,200°C. Start forging at 1,150°C, finish above 950°C. After forging, cool slowly and anneal.
Corrosion Resistance: Superior to 410 and 420 stainless steels, comparable to 304 in many environments. Resists chloride stress corrosion cracking better than 304.
Polishing: Can be polished to a high finish. Passivation after polishing enhances corrosion resistance.
Quality Inspection & Control of 17-4PH Steel
Full-process control:
- Raw material and manufacturer control
- Test : Chemical composition, mechanical properties, UT(ultrasonic testing), specification, surface condition, straightness, etc.
- Packing: Wooden case or pallet or VCI plastic film
Why Purchase AISI 17-4PH from Keyspark Steel?
Fully Customizable: Dimensions, heat treatment, and hardness – all adjustable per batch order.
Certified Quality: Each batch comes with MTC certificate (EN 10204 3.1/3.2) , full chemical and mechanical test report.
ESR Option: Premium quality with Electro-Slag Remelting available for critical applications.
Stable Production: Large forging and rolling capacity ensures consistent quality across orders.
Long-Term Supply: Reserved production slots for regular customers – no interruptions.
Neutral Packaging: Oiled, wrapped, and strapped.
FAQ of 17-4PH
Q1: What is 17-4PH stainless steel?
A: 17-4PH stainless steel is martensitic precipitation hardening stainless steel. Its Chinese grade is 0Cr17Ni4Cu4Nb (UNS S17400 / AISI 630). Typical composition: C ≤0.07%, Cr 15.0–17.5%, Ni 3.0–5.0%, Cu 3.0–5.0%, Nb+Ta 0.15–0.45%. It uses solution treatment (rapid cool at 1020–1060°C) plus aging treatment (480–620°C) to get different strength levels. Aging at 480°C gives tensile strength ≥1310 MPa and hardness ≥40 HRC. It is widely used in aerospace, chemical, oil, medical device industries.
Q2: Is 17-4 stainless steel magnetic?
A: Yes. 17-4PH material is ferromagnetic alloy. Its main matrix is martensite, and martensite has ferromagnetism. So both solution state and aging state show magnetism. Aging temperature changes magnetic property. Saturation magnetization reaches peak near 455°C. When temperature is over 566°C, austenite forms, and magnetism slowly drops.
Q3: What heat treatment is used for 17-4PH stainless steel?
A: Standard heat treatment for 17-4PH is solution treatment plus aging (such as H900). Solution treatment: hold at 1040°C then cool fast to get martensite structure. Then do aging treatment. Common options: H900 (480°C /1h), H1025 (550°C), H1075 (580°C), H1150 (620°C). Higher aging temperature brings lower strength and better toughness. H900 tensile strength ≥1310 MPa; H1150 drops to ≥930 MPa. Some products use extra 815°C intermediate treatment to refine martensite lath and balance strength and ductility.
Q4: What are the main applications of 17-4PH stainless steel?
A: Main uses: aerospace (airframe parts, landing gear, turbine blades, fasteners), oil & gas (valves, pump shafts, downhole parts), medical devices (surgical tools, dental tools, orthopedic parts), chemical industry (high-pressure valves, pump parts), nuclear industry (nuclear waste storage containers), marine field (propeller shafts, valve stems). Max working temperature is around 315°C. Its corrosion resistance is close to 304 stainless steel in most environments.
Q5: How does heat treatment affect the corrosion resistance of 17-4PH?
A: Heat treatment improves corrosion resistance by uniform structure and fine grains. After H900 treatment, corrosion potential rises about +0.04 V, breakdown potential rises about +0.13 V. Mechanism: Heat treatment removes copper segregation at δ ferrite / martensite boundary. It makes NbC precipitate and refine copper-rich precipitates. A denser and more stable passive film forms, and chromium-depleted zones under the film disappear.
Q6: How does the strength of 17-4PH compare to 304 stainless steel?
A: The strength of 17-4PH is much higher than 304 stainless steel. The room-temperature yield strength of 304 is only about 35 ksi (around 240 MPa), while the yield strength of AISI 17-4PH after age hardening can reach over 170 ksi (around 1170 MPa). For H900 condition, its yield strength is more than 4 times that of 304, tensile strength can reach 1310 MPa with hardness about HRC 40, whereas 304 only has hardness around HRC 20 (85 HRB). Therefore, material 17-4PH is suitable for structural parts requiring high load capacity, high strength and corrosion resistance, while 304 fits general applications focusing on corrosion resistance and formability.
