17-4PH round bar – ASTM A564 Type 630 / AMS 5643
Rolled or forged precipitation-hardening stainless bar, condition A or H1150
17-4PH (UNS S17400) round bar normally supplied solution annealed (condition A), for the customer to machine and age to the desired condition, or already aged in H1150/H1150D for direct machining and H2S service. Same material as the 17-4PH page; this data sheet covers the bar form.
Designations and equivalents
| System | Designation |
|---|---|
| UNS | S17400 |
| W.Nr./EN | 1.4542 (X5CrNiCuNb16-4) |
| DIN | X5CrNiCuNb16-4 |
| JIS | SUS630 |
| Trade names | 17-4PH, Type 630 |
| Others | AMS 5622 (VAR remelt) |
Standards by product form
| Form | Standard |
|---|---|
| Bar (industrial) | ASTM A564 Type 630 / ASME SA-564 |
| Bar (aerospace) | AMS 5643 (cond. A); AMS 5622 (VAR) |
| General requirements and tolerances | ASTM A484 |
| H2S service | NACE MR0175/ISO 15156 (H1150D, ≤ 33 HRC) |
| Forging | ASTM A705 Type 630 |
Tolerances and HS codes
- Forged bars (round and square): machining allowance from 2 mm (Ø 6–16 mm) to 24 mm (Ø 400–500 mm) on the diameter. E.g. Ø 100–125 mm finished: +7 mm, tolerance +6 / −0 (length up to 3,500 mm).
- Forged discs: allowance of 4 to 9 mm on the diameter and 3 to 11 mm on the height, plus-only tolerance.
- Cutting and machining: band saw −0 / +5 to +15 mm on length; waterjet +10 % of thickness on the diameter (min. 2 mm); machined parts −0 / +2 to +5 mm on the diameter. See the full tables (INF 002 and INF 003, the same for every alloy).
| Form | NCM (Brazil, 8 digits) | HS (international, 6 digits) | HTS (USA, 10 digits)* | CN (European Union, 8 digits)* |
|---|---|---|---|---|
| Forged bar | 7222.30.00 | 7222.30 | 7222.30.0024 | 7222 30 51 |
| Hot-rolled bar | 7222.11.00 | 7222.11 | 7222.11.0059 | 7222 11 11 |
| Flange and fitting | 7307.21.00 | 7307.21 | 7307.21.5000 | 7307 21 00 |
Tariff class: stainless steel (by chemical composition, under the Chapter 72 Notes and Section XV Note 5).
*: US and EU codes for reference. NCM per current legislation (General Rules of Interpretation, Notes to Chapters 72, 74 and 75 and Section XV Note 5). Confirm the final code with your customs broker according to the item size and finish. HS = first 6 digits of the NCM.
Chemical composition (%)
ASTM A564 Type 630
| Element | Range (%) |
|---|---|
| C | ≤ 0.07 |
| Mn | ≤ 1.00 |
| Si | ≤ 1.00 |
| P | ≤ 0.040 |
| S | ≤ 0.030 |
| Cr | 15.0 – 17.5 |
| Ni | 3.0 – 5.0 |
| Cu | 3.0 – 5.0 |
| Nb + Ta | 0.15 – 0.45 |
| Fe | balance |
Mechanical properties
Usual bar supply conditions (ASTM A564 minimums); others in the aging table
| Property | Value |
|---|---|
| Condition A (solution annealed) | ≤ 363 HB / 38 HRC; no tensile requirement |
| H1150 – Rp0.2 / Rm | ≥ 725 / ≥ 930 MPa |
| H1150 – A / RA | ≥ 16% / ≥ 50% |
| H1150 – Hardness | ≥ 277 HB / 28 HRC |
| H1150D (NACE) | Rp ≥ 725 MPa; ≤ 33 HRC |
| H900 (after aging) | Rp ≥ 1,170 / Rm ≥ 1,310 MPa; ≥ 40 HRC |
Typical physical properties
| Property | Value |
|---|---|
| Density | 7.78 g/cm³ (A) |
| Melting range | 1,404 – 1,440 °C |
| Modulus of elasticity | 196 GPa |
| Thermal conductivity (100 °C) | 17.9 W/m·K |
| Thermal expansion (20–100 °C) | 10.8 µm/m·K |
Aging conditions
| Condition | Aging | Min. Rp0.2 | Min. Rm | Min. A | Min. hardness |
|---|---|---|---|---|---|
| A (solution annealed) | 1,040 ± 15 °C, cool < 30 °C | – | – | – | ≤ 363 HB / 38 HRC max. |
| H900 | 482 °C / 1 h / air | 1,170 MPa | 1,310 MPa | 10% | 388 HB / 40 HRC |
| H925 | 496 °C / 4 h / air | 1,070 MPa | 1,170 MPa | 10% | 375 HB / 38 HRC |
| H1025 | 552 °C / 4 h / air | 1,000 MPa | 1,070 MPa | 12% | 331 HB / 35 HRC |
| H1075 | 579 °C / 4 h / air | 860 MPa | 1,000 MPa | 13% | 311 HB / 32 HRC |
| H1100 | 593 °C / 4 h / air | 795 MPa | 965 MPa | 14% | 302 HB / 31 HRC |
| H1150 | 621 °C / 4 h / air | 725 MPa | 930 MPa | 16% | 277 HB / 28 HRC |
| H1150M | 760 °C / 2 h / air + 621 °C / 4 h / air | 515 MPa | 795 MPa | 18% | ≈ 255 HB (typical) |
Heat treatment, welding and machining
| Item | Usual practice |
|---|---|
| Service temperature | Up to ≈ 315 °C. |
| Heat treatment | Solution annealing (condition A) at 1,040 ± 15 °C, air or oil cooling to < 30 °C; machine in A and age afterwards. Aging (ASTM A564, bar minimums): H900 482 °C/1 h → Rp0.2 1,170 / Rm 1,310 MPa, 40 HRC; H925 496 °C/4 h → 1,070/1,170 MPa, 38 HRC; H1025 552 °C/4 h → 1,000/1,070 MPa, 35 HRC; H1075 579 °C/4 h → 860/1,000 MPa, 32 HRC; H1100 593 °C/4 h → 795/965 MPa, 31 HRC; H1150 621 °C/4 h → 725/930 MPa, 28 HRC; H1150M 760 °C/2 h + 621 °C/4 h → 515/795 MPa (≈ 255 HB). H1150D (621 °C/4 h twice, ≤ 33 HRC) is the condition accepted by NACE MR0175/ISO 15156 for H2S service. Usual sizes (typical, confirm stock): Ø 6.35 to ≈ 300 mm (1/4" to 12"), rolled, peeled, turned or ground bar h9/h11; ASTM A484 tolerances. |
| Welding | Welding is unusual on bar; when necessary use AWS ER630 and re-age. |
| Machining | Machine in A or H1150 and age afterwards; allow for 0.05–0.10% contraction during aging. |
Filler metal for welding
The wire composition is usually not identical to the material: each page explains why.
Typical applications
- Pump and propeller shafts
- Valve stems
- High-strength studs and bolts
- Aircraft hardware
- Bushings, couplings and wear rings
- Shafts for food and paper equipment
- Hydrojetting: high-pressure pumps and components (high strength allows thinner walls, with corrosion resistance)
- Load cells and scale cells: high-strength, corrosion-resistant spring element with low hysteresis and creep*
Alternatives: 15-5PH (AMS 5659) for transverse toughness in large diameters; quenched and tempered 431 for lower cost; Nitronic 50 or duplex when chlorides and SCC are present.
17-4PH round bar: complete guide
17-4PH round bar: standards and supply condition
17-4PH round bar is produced to ASTM A564 Type 630 and, for aerospace use, AMS 5643. The two standards cover the same composition and the same heat treatment conditions; AMS adds process control and testing requirements. For H2S service NACE MR0175 / ISO 15156 applies, which requires condition H1150D or H1150M with hardness up to 33 HRC.
Supply conditions
In condition A, solution annealed at 1,040 °C, the bar has a hardness of about 30 to 36 HRC and is the choice when the customer will machine and age the finished part. In conditions H1150 and H1150D the bar is already aged, with a minimum yield strength of 725 MPa and, in H1150, a minimum tensile strength of 930 MPa and minimum hardness of 277 HBW (in H1150D: minimum tensile strength of 862 MPa and hardness of 255 to 311 HBW, 24 to 33 HRC), ready for use and with the best toughness of the family. The other conditions, from H900 to H1100, are supplied to order or performed by Dustre under its heat treatment service.
Finishes and tolerances
Bars are peeled or turned, with ASTM A484 dimensional tolerances, and can be ground to order. As aging causes a contraction of 0.05 to 0.10%, parts with tight tolerances should be machined with stock allowance and finished after treatment.
Sizes and cutting
Dustre keeps 17-4PH round bars in commercial diameters and supplies other sizes to order; the range available in stock should be checked at the time of ordering. Band saw cutting delivers billets to the exact length, reducing material waste.
Machining and welding
Machining is preferably done in condition A or H1150, with rigid tools and abundant coolant, and the part is aged afterwards.
Applications of 17-4PH round bar
Pump and propeller shafts, valve stems, pins and bushings, high-strength bolts and studs, hydraulic fittings, wear rings and components for oil and gas, aerospace and process equipment.
Supply forms and Dustre services
Round bars and blocks forged in open die, cut to size on a band saw, with rough or finish machining, heat treatment (quenching and tempering, annealing, solution annealing and aging) in our own furnaces and hardness, tensile and impact testing. All material is supplied with a 3.1 inspection certificate and heat traceability.
Frequently asked questions
What is the chemical composition of 17-4PH round bar?
Per ASTM A564 Type 630: C ≤ 0.07; Mn ≤ 1.00; Si ≤ 1.00; P ≤ 0.040; S ≤ 0.030; Cr 15.0 – 17.5.
Which standards cover 17-4PH round bar?
Bar (industrial): ASTM A564 Type 630 / ASME SA-564. Bar (aerospace): AMS 5643 (cond. A); AMS 5622 (VAR). General requirements and tolerances: ASTM A484. H2S service: NACE MR0175/ISO 15156 (H1150D, ≤ 33 HRC). Forging: ASTM A705 Type 630.
Up to what temperature can 17-4PH round bar be used?
Up to ≈ 315 °C.
Which materials can replace 17-4PH round bar?
15-5PH (AMS 5659) for transverse toughness in large diameters; quenched and tempered 431 for lower cost; Nitronic 50 or duplex when chlorides and SCC are present.
Is 17-4PH used for load cells?
Yes. Aged 17-4PH is used for the spring element of load cells and scale cells: its high strength lets it work in the elastic range with enough strain for the strain gauges, it resists corrosion without coating and it has low hysteresis and creep*. Load cell makers list 17-4PH and 15-5PH as element materials.
