Martensitic stainless steel · EN 10283 / EN 10213
GX4CrNi13-4 · 1.4317 13Cr-4Ni soft martensitic stainless steel. Cast equivalent of CA6NM, forged as 1.4313 / F6NM. Bars, hollow bars, sleeves, seamless rolled rings, flanges, discs and finished valve and pump parts.
GX4CrNi13-4, EN material number 1.4317, is a soft martensitic corrosion-resistant steel with max 0.06 % carbon, 12.00 to 13.50 % chromium, 3.50 to 5.00 % nickel and up to 0.70 % molybdenum. It sits among the martensitic grades of EN 10283 for corrosion resistant steel castings, and is also used under EN 10213 for pressure purposes. Density is 7.7 kg/dm³. Quenched and tempered, it gives 760 to 960 MPa tensile strength at 550 to 570 MPa proof strength.
The grade is the European counterpart of ASTM CA6NM (UNS J91540). Because the G prefix denotes a casting, the forged counterpart is X3CrNiMo13-4 / 1.4313 / UNS S41500 / ASTM A182 F6NM.
Jiangyin Jiangnan Metal Co., Ltd. melts and forges this chemistry at its own works in Jiangyin, Jiangsu, China. Minimum order 10 kg, lead time 20 to 60 days. Telephone +86 189 2135 9659, email sales@steelforgepieces.com.
- EN number
- 1.4317
- Standard
- EN 10283, EN 10213
- Structure
- Soft martensitic, magnetic
- Density
- 7.7 kg/dm³
- Tensile +QT
- 760 to 960 MPa
- Proof +QT
- 550 to 570 MPa
- Cast equivalent
- CA6NM / J91540
- Forged equivalent
- 1.4313 / S41500 / F6NM
Read this before ordering: cast designation versus forged designation
The letter G in GX4CrNi13-4 is the European prefix for a cast steel. Material 1.4317 therefore belongs to EN 10283, the standard for corrosion resistant steel castings. A forged bar, ring, flange or disc cannot strictly be certified to it.
When a drawing calls for forged product in 13Cr-4Ni, the grade to specify is X3CrNiMo13-4 / EN 1.4313 / UNS S41500 / ASTM A182 F6NM, also catalogued as AISI 415. We forge that grade and routinely supply it against specifications first written around GX4CrNi13-4 castings. Send the drawing and we will confirm the grade, the standard and the delivery condition in writing before any steel is melted.
Chemical composition
Limits below are the EN 10283 martensitic-grade values for 1.4317, in percent by mass, maximum unless a range is given.
| C | Si | Mn | P | S | Cr | Mo | Ni |
|---|---|---|---|---|---|---|---|
| 0.06 | 1.00 | 1.00 | 0.035 | 0.025 | 12.00–13.50 | 0.70 | 3.50–5.00 |
Where 1.4317 is ordered to EN 10213 for pressure purposes, residual limits of V 0.08 % max and Cu 0.30 % max are commonly added. Published chromium bands vary slightly between references, some quoting 12.0 to 13.0 %; we certify to the band in the standard named on the order. For regulated markets, sulphur between 0.015 and 0.030 % is recommended by EN 10283.
Cross-reference with the ASTM 13Cr-4Ni grades
| Standard | Grade | C | Mn | Si | P | S | Cr | Ni | Mo |
|---|---|---|---|---|---|---|---|---|---|
| EN 10283 | GX4CrNi13-4 (1.4317) | 0.06 | 1.00 | 1.00 | 0.035 | 0.025 | 12.00–13.50 | 3.50–5.00 | 0.70 |
| ASTM A352 / A743 / A487 | CA6NM (J91540) | 0.06 | 1.00 | 1.00 | 0.04 | 0.030 | 11.5–14.0 | 3.5–4.5 | 0.4–1.0 |
| ASTM A757 | E3N | 0.06 | 1.00 | 1.00 | 0.03 | 0.03 | 11.5–14.0 | 3.5–4.5 | 0.4–1.0 |
| EN 10088-2 | X3CrNiMo13-4 (1.4313) | 0.05 | 1.5 | 0.7 | 0.04 | 0.015 | 12.0–14.0 | 3.5–4.5 | 0.3–0.7 |
| ASTM A182 | F6NM (S41500) | 0.05 | 0.5–1.0 | 0.6 | 0.03 | 0.030 | 11.5–14.0 | 3.5–5.5 | 0.5–1.0 |
Two practical differences worth noting on an enquiry. CA6NM, F6NM and S41500 all carry a molybdenum minimum, while 1.4317 sets only a 0.70 % ceiling, so a heat can satisfy 1.4317 and still fall below CA6NM. And 1.4313 carries a nitrogen requirement of min 0.02 % that the ASTM grades do not state. Dual certification has to be agreed before melting.
Mechanical properties
Cast grade 1.4317, quenched and tempered
| Property | Value |
|---|---|
| Rm, tensile strength | 760 to 960 MPa |
| Rp0.2, 0.2 % proof strength | 550 to 570 MPa |
| A, min elongation at fracture | 15 % |
| KV, impact energy at +20 °C | 27 to 50 J |
EN 10283 defines more than one quenched and tempered delivery condition for this grade, distinguished by tempering temperature: 590 to 620 °C, 500 to 530 °C, and 660 to 680 °C. The exact strength minima attached to each class differ between editions of the standard, so state the required condition on the enquiry and we will confirm the guaranteed minima against the current edition rather than quote a figure that may not hold.
Forged grade 1.4313 / S41500 / F6NM
This is the grade most of our customers for this chemistry actually buy, because it is the one that applies to forged product. It is delivered in three strength classes named after the minimum tensile strength.
| Condition | Rm (MPa) | Re yield (MPa) | A (%) | KV (J) | Hardness |
|---|---|---|---|---|---|
| +A annealed | max 1100 | – | – | – | max 320 HBW |
| +QT650 | 700–850 | min 520 | min 15 | min 70 | – |
| +QT780 | 780–980 | min 620 | min 15 | min 70 | – |
| +QT900 | 900–1100 | min 800 | min 12 | min 50 | – |
| +QT to EN 10028-7 | 780–980 | min 650 | min 14 | min 70 | – |
Proof strength of 1.4313 at raised temperature
Minimum Rp0.2 in MPa. These are the figures that decide whether a part can hold pressure warm, and they are the reason the grade is limited to roughly 300 °C in service.
| Condition | 100 °C | 150 °C | 200 °C | 250 °C | 300 °C | 350 °C | 400 °C |
|---|---|---|---|---|---|---|---|
| +QT650 | 500 | 490 | 480 | 470 | 460 | 450 | – |
| +QT780 | 590 | 575 | 560 | 545 | 530 | 515 | – |
| +QT900 | 720 | 690 | 665 | 640 | 620 | – | – |
| Modulus E (GPa) | 195 | – | 185 | – | 175 | – | 170 |
| Expansion (10-6 K-1) | 10.5 | – | 10.9 | – | 11.3 | – | 11.6 |
Physical properties of 1.4317
| Property | Value | Condition |
|---|---|---|
| Density | 7.7 kg/dm³ | – |
| Specific heat | 460 J/(kg·K) | at 20 °C |
| Thermal conductivity | 26 W/(m·K) | at 50 °C |
| Thermal conductivity | 27 W/(m·K) | at 100 °C |
| Mean thermal expansion | 10.5 × 10-6 K-1 | 20 to 100 °C |
| Magnetic response | Ferromagnetic | all conditions |
Equivalent grades
| Region and standard | Cast designation | Wrought designation for forgings |
|---|---|---|
| Europe, EN | GX4CrNi13-4 · 1.4317 | X3CrNiMo13-4 · 1.4313 |
| USA, ASTM and UNS | CA6NM · J91540 (A743, A352, A487 Cl. A and B); A757 E3N | S41500 · A182 F6NM · AISI 415 |
| Germany, older DIN | G-X5 CrNi 13 4 | X4 CrNi 13 4 |
| France, AFNOR | – | Z6CN13-04 · Z4CN13-4 |
| United Kingdom, BS | – | 425C11 · 425C12 |
| Japan, JIS | SCS5 | – |
| China, GB | – | 04Cr13Ni5Mo · 0Cr13Ni5Mo |
| Sour service | – | NACE MR0175 listed |
Equivalency here is a guide for enquiry, not a certification statement. Chemistry bands, test temperatures and acceptance criteria differ between EN and ASTM, and references disagree on the Swedish designation, which is given variously as SS 2384 and SS 2385. Every cross-certification is confirmed in writing before melting.
Forged product forms
Everything below is forged from a single piece of steel melted at our own works, with no welding, no casting and no purchased billet of unknown origin.
| Form | Shapes | End use |
|---|---|---|
| Bars | Round, square, rectangular and flat, hexagonal | Shafts, stems, pins, machining stock |
| Hollow forgings | Hollow bars, sleeves, bushes, bushings, cylinders, barrels, casings, shells, hubs, housings | Pump and compressor housings, liners |
| Rings | Seamless rolled rings, forged rings, retaining rings, valve seat rings | Turbine rings, bearing races, gear ring blanks |
| Flat forgings | Flanges, blocks, discs, plates, tube sheets | Pressure flanges, closure plates, blind discs |
| Valve parts | Bodies, bonnets, seats, seat rings, stems | Hydro, oil and gas, and water valves |
| Rotating parts | Pump and compressor components, hydro turbine parts | Runners, runner crowns, wicket gates, impellers |
| Tooling | Dies and die blocks for pressure die casting | Die blocks, inserts |
Where the grade is used
Hydroelectric turbine components, pump casings and impellers, valve bodies and bonnets, valve stems and seat rings, compressor parts, pressure-retaining components at room and raised temperature, and dies for pressure die casting. The wrought grade covers parts and components working up to about 300 °C in corrosive environments, chloride service excepted.
Forging, heat treatment and welding
Forging and heat treatment
The wrought grade is forged and rolled at about 1150 °C with air cooling. Hardening follows at 950 to 1050 °C in oil or air, then tempering sets the class: 650 to 700 °C followed by 600 to 620 °C for QT650, 550 to 600 °C for QT780, and 520 to 580 °C for QT900. Annealed material is treated at 600 to 650 °C and cooled in air or in the furnace. For the cast grade 1.4317, quenching is at 1000 to 1050 °C with tempering at 590 to 620 °C, 500 to 530 °C or 660 to 680 °C according to the condition ordered.
Welding, with a caution
References do not agree on this point, and it is worth settling early rather than at the fabrication stage. For the cast grade 1.4317, published welding conditions call for a preheat of 100 to 200 °C, an interpass temperature of no more than 300 °C, and a post-weld tempering heat treatment. For the wrought grade 1.4313, at least one supplier datasheet states plainly that the steel is not suitable for welding. If your design depends on welding, qualify the procedure against the governing specification and tell us at enquiry stage so the delivery condition can be chosen to suit.
Machining
Machine in the tempered condition, not as quenched. For large rings and discs the normal sequence is rough machining before the final temper and finish machining afterwards. We can supply at any stage from black forged through proof machined to finish machined.
Why order this grade from our works
Most forging suppliers in China buy billet. This plant starts one step earlier, at the furnace. Carbon, alloy, stainless and duplex grades run through the electric arc furnace, are refined in a ladle furnace and, where low carbon or tight nitrogen control is needed, are decarburised under vacuum. For a 13Cr-4Ni grade that matters twice over: the 0.05 to 0.06 % carbon ceiling and the nitrogen requirement in 1.4313 are both set in the melt shop, not on the press.
| Field | Detail |
|---|---|
| Legal name | Jiangyin Jiangnan Metal Co., Ltd. |
| Established | 1997 |
| Works | No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China |
| People | 460, including 9 senior engineers, 32 intermediate engineers and 140 technicians |
| Melting | EF, LF, VOD, VIM, VAR, ESR. 60 t maximum heat |
| Forging | 6,300 t open-die press, 6 m radial-axial ring mill, 30 t maximum single piece |
| Heat treatment | 14 furnaces, including 15 m deep well furnaces for vertical quenching |
| Approvals | CCS, BV, DNV, LR, NK |
| Minimum order | 10 kg, no minimum piece count |
| Lead time | 20 to 60 days |
Because melting, forging, heat treatment, machining and testing all happen on one site, the certificate traces a part back to its melt number instead of stopping at a purchased billet.
Testing and certification
Every forging ships with an EN 10204 3.1 mill test certificate recording the heat number, the chemical analysis, the heat-treatment condition and the mechanical test results. Available on request: ultrasonic inspection, magnetic particle and dye penetrant inspection, hardness survey, Charpy V-notch impact testing at ambient or low temperature, intergranular corrosion testing, grain size and microstructure evaluation, and dimensional reports. EN 10204 3.2 certification with a third-party witness such as TÜV, BV, SGS, Lloyd's or your own inspector can be arranged at order stage.
Questions we are asked
Is GX4CrNi13-4 a cast grade or a forged grade?
The G prefix marks it as a cast designation, so 1.4317 belongs to EN 10283, the casting standard. For forged bars, rolled rings, flanges, discs and sleeves in the same 13Cr-4Ni chemistry, specify X3CrNiMo13-4 / 1.4313 / UNS S41500 / ASTM A182 F6NM. We forge that grade and match it against specifications written for GX4CrNi13-4 castings.
What is the American equivalent of 1.4317?
Grade CA6NM, UNS J91540, found in ASTM A743, ASTM A352 and ASTM A487 Classes A and B, plus ASTM A757 Grade E3N. CA6NM runs 11.5 to 14.0 % Cr, 3.5 to 4.5 % Ni and 0.4 to 1.0 % Mo. The bands overlap 1.4317 without matching it, and CA6NM sets a molybdenum minimum that 1.4317 does not.
What tensile strength can I expect?
For the cast grade in the quenched and tempered condition, 760 to 960 MPa tensile at 550 to 570 MPa proof, 15 % minimum elongation and 27 to 50 J impact energy at +20 °C. For the forged grade 1.4313, choose a class: QT650 at 700 to 850 MPa, QT780 at 780 to 980 MPa, or QT900 at 900 to 1100 MPa.
Can it be welded?
Sources conflict and the answer depends on which designation you are buying. Published welding conditions for the cast grade give a 100 to 200 °C preheat, interpass of max 300 °C and a post-weld temper. One supplier datasheet for the wrought grade 1.4313 states it is not suitable for welding. Qualify the procedure against your governing specification before committing to a welded design, and raise it with us at enquiry stage.
Is the grade magnetic?
Yes. It is martensitic and ferromagnetic in every delivery condition, unlike austenitic grades such as 304 and 316.
What is the minimum order and the lead time?
Minimum order is 10 kg with no minimum piece count, so single prototype pieces are accepted. Lead time runs 20 to 60 days depending on section size, heat-treatment class and test scope. Send the drawing to sales@steelforgepieces.com for a firm date with the quotation.
How large a piece can you forge in this grade?
Up to 30 t as a single piece, limited by the 60 t heat size and the 6,300 t press. Seamless rolled rings go to 6,000 mm outside diameter on the 6 m radial-axial mill, and shafts up to 14,000 mm turned length, with 15 m deep well furnaces available for vertical quenching.