# X2CrNiMoN17-11-2 (1.4406 / 316LN) Open-Die Forgings

Jiangyin Jiangnan Metal Co., Ltd.
No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
+86 189 2135 9659 | sales@steelforgepieces.com
https://www.steelforgepieces.com/Stainless-Steel/X2CrNiMoN17-11-2.html
Last reviewed 21 September 2026

## Grade summary

X2CrNiMoN17-11-2 is the EN 10027-1 name for austenitic stainless steel number 1.4406. It is a low-carbon molybdenum grade, carbon capped at 0.030 %, with 0.12 to 0.22 % nitrogen added. That nitrogen puts the specified minimum proof strength at 280-315 MPa, about 40 % above 316L, and does not cost anything in resistance to intergranular corrosion. The grade is equivalent to AISI 316LN and UNS S31653.

Jiangyin Jiangnan Metal forges this grade into bars, seamless rolled rings, flanges, discs and hollow sections at its plant in Jiangyin, Jiangsu. Parts ship solution annealed with an EN 10204 3.1 certificate.

## Quick reference

| Property | Value |
|---|---|
| EN name | X2CrNiMoN17-11-2 |
| EN material number | 1.4406 |
| UNS | S31653 |
| AISI / ASTM | 316LN, ASTM A182 F316LN |
| Microstructure | Austenitic |
| Density | 8.0 g/cm3 |
| PREN (Cr + 3.3Mo + 16N) | 25.0 to 30.3, typ. 27.5 |
| Rp0.2 minimum | 280 to 315 MPa |
| Rm | 580 to 800 MPa |
| Minimum service temperature | -270 C |
| Magnetic | No, relative permeability approx. 1.005 |
| Delivery condition | Forged and solution annealed (+AT) |
| Governing standards | EN 10088-1:2023, EN 10088-3:2023, EN 10250-4, EN 10222-5, EN 10272, ASTM A182 |

## What it is

The EN 10027-1 name spells out the chemistry. X marks a high-alloy steel, 2 stands for 0.02 % nominal carbon, CrNiMoN lists the alloying elements in order of content, and 17-11-2 gives their nominal percentages: 17 % chromium, 11 % nickel, 2 % molybdenum. Nitrogen is in there but sits below the level that earns its own figure.

In practice the grade is 316L with nitrogen added on purpose. Nitrogen stabilises austenite and strengthens it in solid solution. At 0.12 to 0.22 % it takes the specified minimum yield from roughly 200 MPa on 316L up to 280-315 MPa, so a pressure part can be designed thinner for the same allowable stress. It also counts 16 times its weight percent in the PREN formula, and it slows sensitisation without adding the carbon that would throw chromium carbides out at the grain boundaries.

On heavy forgings this matters more than it does on sheet. A thick ring or tube sheet cools slowly through the sensitisation range after annealing. The low carbon ceiling working together with the nitrogen is what lets 1.4406 pass EN ISO 3651-2 intergranular corrosion testing both as delivered and after a sensitising treatment.

Note on the standard: bars, forgings and semi-finished products in this grade fall under EN 10088-3, not EN 10088-2, which covers sheet, plate and strip. The current editions are EN 10088-1:2023 and EN 10088-3:2023, which replaced the 2014 editions. Composition limits for 1.4406 did not change in that revision.

## Chemical composition

Cast analysis limits, % by mass, to EN 10088-1:2023 and EN 10088-3:2023.

| C | Si | Mn | P | S | Cr | Ni | Mo | N | Fe |
|---|---|---|---|---|---|---|---|---|---|
| max 0.030 | max 1.00 | max 2.00 | max 0.045 | max 0.015 | 16.5-18.5 | 10.0-12.5 | 2.0-2.5 | 0.12-0.22 | Balance |

- Sulphur can be set to suit the job. Controlled sulphur of 0.015 to 0.030 % machines better, 0.008 to 0.030 % gives a more consistent weld pool, below 0.015 % polishes better.
- Where the part falls under Pressure Equipment Directive 2014/68/EU, EN 10088-1 caps phosphorus at 0.035 %.
- Elements not in the table are not added deliberately without the purchaser's agreement, apart from what is needed to finish the cast.

## Mechanical properties

Solution annealed (+AT), room temperature.

| Property | Symbol | Value | Test standard |
|---|---|---|---|
| Tensile strength | Rm | 580 to 800 MPa | EN ISO 6892-1 |
| 0.2 % proof strength, min. | Rp0.2 | 280 to 315 MPa | EN ISO 6892-1 |
| 1.0 % proof strength, min. | Rp1.0 | 315 to 355 MPa | EN ISO 6892-1 |
| Elongation at fracture, min. | A | 30 to 40 % transverse, 45 % longitudinal | EN ISO 6892-1 |
| Impact energy, longitudinal, +20 C | KV | min 100 J | EN ISO 148-1 |
| Impact energy, transverse, +20 C | KV | min 60 J | EN ISO 148-1 |
| Impact energy, transverse, -196 C | KV | min 60 J | EN ISO 148-1 |
| Brinell hardness, max. | HBW | 250 | EN ISO 6506-1 |

Impact energy is the same at +20 C and at -196 C. Austenite has no transition temperature, which is the reason this grade goes into cryogenic work. Properties for sections above the standard ruling size are agreed at order stage. We test a prolongation from every heat-treatment lot.

## Physical properties

| Property | Value at 20 C |
|---|---|
| Density | 8.0 g/cm3 |
| Modulus of elasticity | 200 GPa |
| Thermal conductivity | 15 W/(m.K) |
| Specific heat capacity | 500 J/(kg.K) |
| Electrical resistivity | 0.75 ohm.mm2/m |
| Thermal expansion, 20 to 200 C | 16.5 x 10-6 K-1 |
| Relative magnetic permeability, annealed | approx. 1.005 |

## Equivalent grades

| System | Designation |
|---|---|
| EN name | X2CrNiMoN17-11-2 |
| EN number | 1.4406 |
| AISI / ASTM | 316LN |
| UNS | S31653 |
| ASTM forgings | A182 Grade F316LN |
| JIS (Japan) | SUS316LN |
| BS (UK, superseded) | 316S61 |
| AFNOR (France) | Z3CND17-11Az |
| GB (China) | 022Cr17Ni12Mo2N |

Cross-references are indicative. Composition limits differ between standards, so verify every element against the applicable specification before substituting a grade.

## Corrosion resistance and PREN

PREN = %Cr + 3.3 x %Mo + 16 x %N

| Grade | Mo % | N % | PREN |
|---|---|---|---|
| 1.4404, 316L | 2.0-2.5 | max 0.11 | 23.1 to 28.5 |
| 1.4406, 316LN | 2.0-2.5 | 0.12-0.22 | 25.0 to 30.3, typ. 27.5 |
| 1.4429, 316LN high-Mo | 2.50-3.00 | 0.12-0.22 | 26.7 to 31.9, typ. 29.3 |

- Intergranular corrosion: passes in the delivery condition and after sensitisation, tested to EN ISO 3651-2.
- Pitting and crevice corrosion: better than 304 / 1.4301 in chloride-bearing media. The nitrogen is worth roughly another 0.5 % molybdenum.
- Stress corrosion cracking: like any standard austenitic, risk climbs above about 60 C in chloride solutions. Where SCC governs, a duplex forging such as F51 (1.4462) or F53 (2507) is the better choice.
- Where a minimum PREN is specified on the order, we pick or order heats toward the top of the Cr, Mo and N ranges and put the calculated figure on the certificate.

## Forging and heat treatment

| Operation | Parameter |
|---|---|
| Heating for forging | 1150 to 1200 C |
| Finish forging temperature | above 950 C |
| Minimum forging ratio | 3:1 from ingot, 2:1 from billet |
| Solution annealing | 1020 to 1120 C |
| Cooling from anneal | Rapid quench in water |
| Hardening | Not applicable, austenitic |
| Stress relief after machining | Optional, 450 to 600 C, by agreement only |

Welding: TIG, MIG, SMAW and SAW, no pre-heat and no post-weld heat treatment on most sections. Matching low-carbon filler, ER316LN or E316L, interpass below about 150 C.

Machining: much like 316L but work hardens faster because of the nitrogen. Sharp positive-rake tooling, rigid setup, heavy constant feeds, plenty of coolant.

## Product forms

| Product form | Typical size range |
|---|---|
| Round bars and rods | dia. 80 to 1200 mm, up to 6000 mm long |
| Square, flat and hex bars | 80 to 900 mm across flats |
| Seamless rolled rings | OD 300 to 4000 mm, height up to 1200 mm |
| Forged rings | OD 200 to 2500 mm |
| Forged flanges | ASME B16.5, B16.47, EN 1092-1, custom sizes |
| Discs, blocks and tube sheets | dia. 200 to 3000 mm, thickness 30 to 800 mm |
| Hollow bars, sleeves, bushings, cylinders | OD 150 to 1500 mm, ID from 80 mm |
| Shafts and stepped shafts | up to 12 t single piece |

Maximum single-piece weight 30 t. All items supplied solution annealed, black or rough machined to the customer's allowance.

## Applications

Cryogenic equipment (LNG terminals, liquid nitrogen and helium vessels, superconducting magnet structures). Pressure vessels and heat exchangers (tube sheets, channel covers, shell flanges, nozzle forgings). Chemical and petrochemical plant (reactor internals, pump and valve bodies, agitator shafts). Offshore and marine (seawater manifolds, subsea structural parts). Nuclear and power (primary circuit components). Pharmaceutical and food (sanitary vessel flanges and fittings).

## Testing and certification

- Heat analysis by optical emission spectrometry, nitrogen by inert gas fusion. Product analysis on request.
- Tensile to EN ISO 6892-1, Charpy V-notch at +20 C and on request at -196 C or -269 C to EN ISO 148-1, Brinell hardness to EN ISO 6506-1.
- Intergranular corrosion to EN ISO 3651-2 or ASTM A262 Practice E. ASTM G48 pitting test on request.
- 100 % ultrasonic to EN 10228-3 or ASTM A388 at the agreed acceptance class, liquid penetrant to EN ISO 3452-1, PMI where specified.
- EN 10204 3.1 inspection certificate as standard. EN 10204 3.2 with a TUV, BV, SGS, DNV or Lloyd's Register witness on request.
- Heat number and lot number hard stamped or vibro etched on every piece and carried through to the certificate.

## Frequently asked questions

**Is X2CrNiMoN17-11-2 the same as 316L?**
No. 1.4406 is the nitrogen-alloyed version of 316L (1.4404). Both hold carbon at 0.030 % max, but 1.4406 carries 0.12 to 0.22 % nitrogen. That lifts the specified minimum yield from about 200 MPa to 280-315 MPa and improves pitting resistance. The difference is strength and resistance to sensitisation.

**What is the ASTM or AISI equivalent of X2CrNiMoN17-11-2?**
1.4406 lines up with AISI 316LN, UNS S31653, ASTM A182 grade F316LN, JIS SUS316LN, BS 316S61, AFNOR Z3CND17-11Az and Chinese GB 022Cr17Ni12Mo2N. ISO 15510 lists 1.4406 under S31653 as well.

**What is the difference between 1.4406 and 1.4429?**
Both are nitrogen-alloyed 316LN grades. 1.4406 runs 2.0-2.5 % Mo and 10.0-12.5 % Ni. 1.4429 runs 2.50-3.00 % Mo and 11.0-14.0 % Ni. The extra molybdenum puts the PREN of 1.4429 at 26.7-31.9 against 25.0-30.3 for 1.4406.

**What is the PREN of X2CrNiMoN17-11-2?**
Between 25.0 and 30.3 on the composition limits, with a mid-range figure near 27.5.

**Can X2CrNiMoN17-11-2 be used at cryogenic temperatures?**
Yes. Austenite has no ductile-to-brittle transition, and the grade holds a minimum transverse impact energy of 60 J at -196 C. It is used down to -270 C.

**Is X2CrNiMoN17-11-2 magnetic?**
Solution annealed, it is effectively non-magnetic, with relative permeability around 1.005.

**What forging and heat-treatment parameters do you use?**
Ingot or billet goes in at 1150 to 1200 C, is forged at a minimum 3:1 reduction and finished above 950 C. Parts are then solution annealed at 1020 to 1120 C and water quenched. The grade cannot be hardened by heat treatment.

**What certification comes with the forgings?**
An EN 10204 3.1 inspection certificate as standard. EN 10204 3.2 with a third-party witness is available if asked for at enquiry.

**What is the minimum order quantity and lead time?**
Single pieces and prototypes are accepted, with no tonnage minimum on a machined forging. Lead time normally runs 25 to 40 days from order confirmation on items forged from stock billet.

**How do I request a quotation?**
Send the drawing or finished dimensions, quantity, applicable specification, certification required and any NDE class to sales@steelforgepieces.com, or call +86 189 2135 9659.

## About the manufacturer

Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging plant at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, about 150 km from the Port of Shanghai. We forge bars, seamless rolled rings, flanges, discs, tube sheets, shafts and hollow sections in stainless steel, nickel alloy, alloy steel, tool steel and carbon steel, certified to EN, ASTM, ASME, DIN, JIS and GB specifications.

## Citation

Jiangyin Jiangnan Metal Co., Ltd., "X2CrNiMoN17-11-2 (1.4406 / 316LN) Open-Die Forgings", https://www.steelforgepieces.com/Stainless-Steel/X2CrNiMoN17-11-2.html, reviewed 21 September 2026.

Data is taken from EN 10088-1:2023, EN 10088-3:2023, EN 10250-4, EN 10222-5, ASTM A182/A182M and ISO 15510, together with Jiangyin Jiangnan Metal's own production practice. Figures are for guidance. What governs any order is the applicable specification and the material certificate.