17-4PH β most widely used PH stainless. Rm up to 1310 MPa in H900. Combines stainless corrosion resistance with high-strength alloy steel mechanical properties.
X5CrNiCuNb16-4 (EN 1.4542 / UNS S17400 / AISI 630) is a martensitic precipitation-hardening stainless steel. Its unique strengthening mechanism β precipitation of copper-rich intermetallic particles during aging β allows properties to be tailored across a wide range by selecting the aging temperature. Solution-annealed (Condition A) material is relatively soft (HRC ~28-32) and readily machined; after aging at 482 C (H900) it reaches Rm >1310 MPa with HRC 40-44, approaching high-strength alloy steels. Corrosion resistance is comparable to AISI 304 in most environments. Per Sandmeyer Steel / ASTM A564 data.
| Standard Body | Designation | Country / Region | Note |
|---|---|---|---|
| EN | X5CrNiCuNb16-4 | European Union | |
| DIN | 1.4542 | Germany | |
| AISI/SAE | 630 / 17-4PH | USA | |
| ASTM | A564 Type 630 / A693 / A705 | USA | |
| AMS | AMS 5604 (bar/billet) / AMS 5622 (plate/sheet) | USA (Aerospace) | |
| UNS | S17400 | USA (UNS) | |
| BS EN | 1.4542 | UK | |
| JIS | SUS630 | Japan | |
| GOST | 09H17N7YU2 (09Kh17N7YU2) | Russia / CIS | |
| UNI | X5CrNiCuNb16-4 | Italy | |
| NF | Z7CNU17-04 | France | |
| ISO | X5CrNiCuNb16-4 (ISO 15510) | International | |
| GB | 0Cr17Ni4Cu4Nb | China | |
| JUS | C.4542 | Yugoslavia / Serbia | PH martensitic stainless steel; JUS C.B2.090 |
| API | API 6A 17-4PH | International |
| # | Standard Body | Designation | Country / Region | Note |
|---|---|---|---|---|
| 1 | EN | X5CrNiCuNb16-4 | European Union | β |
| 2 | DIN | 1.4542 | Germany | β |
| 3 | AISI/SAE | 630 / 17-4PH | USA | β |
| 4 | ASTM | A564 Type 630 / A693 / A705 | USA | β |
| 5 | AMS | AMS 5604 (bar/billet) / AMS 5622 (plate/sheet) | USA (Aerospace) | β |
| 6 | UNS | S17400 | USA (UNS) | β |
| 7 | BS EN | 1.4542 | UK | β |
| 8 | JIS | SUS630 | Japan | β |
| 9 | GOST | 09H17N7YU2 (09Kh17N7YU2) | Russia / CIS | β |
| 10 | UNI | X5CrNiCuNb16-4 | Italy | β |
| 11 | NF | Z7CNU17-04 | France | β |
| 12 | ISO | X5CrNiCuNb16-4 (ISO 15510) | International | β |
| 13 | GB | 0Cr17Ni4Cu4Nb | China | β |
| 14 | JUS | C.4542 | Yugoslavia / Serbia | PH martensitic stainless steel; JUS C.B2.090 |
| 15 | API | API 6A 17-4PH | International | β |
| Element | Symbol | Min % | Max % | Typical % |
|---|---|---|---|---|
| Carbon | C | β | 0.0700 | 0.0400 |
| Manganese | Mn | β | 1.0000 | 0.6000 |
| Silicon | Si | β | 1.0000 | 0.5000 |
| Chromium | Cr | 15.0000 | 17.5000 | 16.5000 |
| Nickel | Ni | 3.0000 | 5.0000 | 4.0000 |
| Copper | Cu | 3.0000 | 5.0000 | 4.0000 |
| Niobium (+ Ta) | Nb | 0.1500 | 0.4500 | 0.2800 |
| Phosphorus | P | β | 0.0400 | β |
| Condition | Code | Rm min MPa | Rm max MPa |
Re min MPa | Re max MPa |
Aβ
min % |
Z % |
KV J |
HB min | HB max | HRC min | HRC max | E GPa |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Condition A β Solution Annealed | +A | 930 | 1,100 | 580 | 860 | 16.0 | β | β | β | 321 | 28.0 | 34.0 | 193.0 |
| H900 β Aged 482 C / 1h | H900 | 1,170 | 1,380 | 1,070 | 1,240 | 8.0 | β | β | β | β | 40.0 | 44.0 | 197.0 |
| H925 β Aged 496 C / 4h | H925 | 1,170 | 1,310 | 1,000 | 1,170 | 8.0 | β | β | β | β | 38.0 | 42.0 | 197.0 |
| H1025 β Aged 552 C / 4h | H1025 | 1,070 | 1,170 | 1,000 | 1,070 | 12.0 | β | 60.0 | β | β | 35.0 | 38.0 | 197.0 |
| H1075 β Aged 579 C / 4h | H1075 | 1,000 | 1,100 | 862 | 1,000 | 13.0 | β | β | β | β | 32.0 | 36.0 | 197.0 |
| H1150 β Aged 621 C / 4h | H1150 | 862 | 1,000 | 793 | 930 | 14.0 | β | β | β | β | 28.0 | 32.0 | 197.0 |
| Coolant | Flood coolant or cutting oil β mandatory |
| Chip Formation | Short-medium chips; work-hardening in Condition A |
| Tool Material | Machine in Cond.A: TiAlN carbide positive rake; after aging: CBN or grinding preferred |
| Surface Finish | Ra 0.4-1.6 um (Cond.A); ground finish (hardened) |