# 1.4449 (X3CrNiMo18-12-3) Material Data Sheet for Open-Die Forgings

**Publisher:** Jiangyin Jiangnan Metal Co., Ltd., Jiangyin, Jiangsu Province, China
**Canonical URL:** https://www.steelforgepieces.com/Stainless-Steel/1.4449.html
**Last reviewed:** 2026-09-22
**Contact:** sales@steelforgepieces.com | +86-189-2135-9659

## Summary

1.4449, EN chemical designation X3CrNiMo18-12-3, is a molybdenum-bearing austenitic chromium-nickel stainless steel listed in EN 10222-5, the European standard for steel forgings for pressure purposes. Composition limits are carbon 0.035 % maximum, chromium 17.0 to 18.2 %, nickel 11.5 to 12.5 %, molybdenum 2.25 to 2.75 %, nitrogen 0.08 % maximum and copper 1.00 % maximum, balance iron. The low carbon limit resists sensitisation during welding, and the molybdenum raises resistance to pitting and crevice corrosion in chloride-bearing and moderately reducing service.

Jiangyin Jiangnan Metal Co., Ltd., an integrated melting works and open-die forging factory in Jiangyin, Jiangsu Province, China, melts its own 1.4449 and forges it into rings, seamless rolled rings, bars, discs, tube sheets, flanges, shafts and valve components, supplied solution annealed with an EN 10204 3.1 certificate.

Key facts:

- Steel type: austenitic Cr-Ni-Mo stainless, low carbon, non-magnetic as solution annealed
- Principal standard: EN 10222-5, steel forgings for pressure purposes
- PREN: 26.5 mid-range, 24.4 at the lean end. On the same basis 316L is 25.8
- Common confusion: 1.4449, 1.4438, 1.4439 and ASTM A182 F317 are different grades; none of the molybdenum ranges overlap
- Manufacturer: Jiangyin Jiangnan Metal Co., Ltd.

## Grade description

1.4449 has a nominal composition of about 18 % chromium, 12 % nickel and 2.5 % molybdenum. Three features of that composition govern how Jiangyin Jiangnan Metal Co., Ltd. forges and heat treats the steel.

**Carbon, 0.035 % maximum.** The limit is roughly half the 0.07 % permitted in a standard 316-class grade and below the 0.08 % of AISI 317. Carbon retained in solution does not precipitate as chromium carbide at the grain boundaries during welding or slow cooling, so local chromium depletion is avoided. Room-temperature strength is reduced slightly, and the nitrogen allowance of up to 0.08 % partly compensates.

**Molybdenum, 2.25 to 2.75 %.** Molybdenum stabilises the passive film against chloride ions, the mechanism behind pitting and crevice attack, and improves performance in moderately reducing acids where chromium alone passivates poorly. This addition accounts for the performance difference between 1.4449 and a 304-class grade.

**Standard basis.** 1.4449 appears in EN 10222-5, which covers steel forgings for pressure purposes, so the acceptance rules, test-piece locations and solution-treatment requirements were written for forged sections from the outset.

## Designations and equivalents

| System | Designation | Note |
| --- | --- | --- |
| EN material number | 1.4449 | German Werkstoff number, also W.Nr. 1.4449 |
| EN chemical name | X3CrNiMo18-12-3 | X3 denotes 0.03 % nominal carbon |
| Principal standard | EN 10222-5 | Steel forgings for pressure purposes, stainless steels |
| Related EN standards | EN 10088-3, EN 10272, EN 10250-4 | Bar, pressure-purpose bar, open-die forgings |
| US cross-reference | AISI 317, UNS S31700 | Family match, composition windows differ |
| ASTM forging grade | ASTM A182 F317 | Forging specification usually quoted alongside |
| French legacy | Z6CND17.12 | AFNOR designation |

### Grades with similar designations

| Grade | EN name | Cr % | Ni % | Mo % | N % | Usual US name |
| --- | --- | --- | --- | --- | --- | --- |
| **1.4449** | X3CrNiMo18-12-3 | 17.0 to 18.2 | 11.5 to 12.5 | 2.25 to 2.75 | 0.08 max | 317 cross-ref |
| 1.4404 | X2CrNiMo17-12-2 | 16.5 to 18.5 | 10.0 to 13.0 | 2.00 to 2.50 | 0.11 max | 316L |
| 1.4438 | X2CrNiMo18-15-4 | 17.5 to 19.5 | 13.0 to 16.0 | 3.00 to 4.00 | 0.11 max | 317L |
| 1.4439 | X2CrNiMoN17-13-5 | 16.5 to 18.5 | 12.5 to 14.5 | 4.00 to 5.00 | 0.12 to 0.22 | 317LMN |
| A182 F317 | UNS S31700 | 18.0 to 20.0 | 11.0 to 15.0 | 3.00 to 4.00 | not specified | 317 |

**Important:** 1.4449 allows 2.25 to 2.75 % molybdenum. ASTM A182 F317, the specification it is most often equated with, requires 3.00 to 4.00 %. Those bands do not overlap at any point, and the chromium ranges overlap by only 0.2 % (17.0 to 18.2 against 18.0 to 20.0). Material certified to EN 10222-5 as 1.4449 will not satisfy an order written against A182 F317, and the reverse also applies. On composition, 1.4449 is closer to an enhanced 316L than to a 317. Jiangyin Jiangnan Metal Co., Ltd. melts to whichever window is nominated. The enquiry must state which standard applies. A single heat cannot be dual-certified to both.

## Chemical composition, weight %

| Element | Min % | Max % | Role |
| --- | --- | --- | --- |
| Iron (Fe) | Balance | Balance | Matrix |
| Chromium (Cr) | 17.0 | 18.2 | Forms the passive film |
| Nickel (Ni) | 11.5 | 12.5 | Stabilises austenite, adds toughness |
| Molybdenum (Mo) | 2.25 | 2.75 | Pitting and crevice resistance |
| Carbon (C) | - | 0.035 | Held low to resist sensitisation |
| Nitrogen (N) | - | 0.08 | Strength and pitting resistance |
| Copper (Cu) | - | 1.00 | Permitted residual |
| Silicon (Si) | - | 1.00 | Deoxidiser |
| Manganese (Mn) | - | 2.00 | Deoxidiser, austenite former |
| Phosphorus (P) | - | 0.045 | Impurity |
| Sulphur (S) | - | 0.015 | Impurity, held low for forgeability |

Published listings of 1.4449 differ slightly on the molybdenum band, some giving 2.25 to 2.75 % and others 2.30 to 2.80 %, depending on the revision of EN 10222-5 they were compiled from. State the standard and revision on the order.

Jiangyin Jiangnan Metal Co., Ltd. melts its own steel, so the heat analysis is verified at the furnace. The certificate carries the measured values, not these limits.

## Mechanical properties at 20 C, solution annealed

| Property | Symbol | Typical, 1.4449 | Minimum, A182 F317 | Unit |
| --- | --- | --- | --- | --- |
| Tensile strength | Rm | 620 | 515 (75 ksi) | MPa |
| 0.2 % proof strength | Rp0.2 | 250 | 205 (30 ksi) | MPa |
| Elongation at break | A | 48 | 30 | % |
| Reduction of area | Z | - | 50 | % |
| Modulus of elasticity | E | 200 | - | GPa |
| Brinell hardness | HB | 190 | - | HB |

The 1.4449 column holds published typical values for solution-annealed material. They are not acceptance criteria and they are not guaranteed by any standard. EN 10222-5 is the only standard covering 1.4449 and published data for the grade is limited. Treat these figures as indicative and work to the minima in the revision nominated on the order, which will be lower. Section size, forging reduction and the solution-treatment cycle all move the measured figures.

1.4449 cannot be hardened by heat treatment. For a design requiring proof strength well above 250 MPa in this corrosion class, a duplex grade such as 1.4462 is the usual selection.

## Physical properties at 20 C

| Property | Value | Unit |
| --- | --- | --- |
| Density | 8.0 | g/cm3 |
| Thermal conductivity | 15 | W/(m K) |
| Specific heat capacity | 500 | J/(kg K) |
| Melting range | 1400 to 1440 | C |
| Electrical conductivity | 2.3 | % IACS |
| Magnetic response | Non-magnetic | solution annealed |

Density and specific heat follow the EN 10088-1 convention for molybdenum-bearing austenitic steels, which assigns 8.0 g/cm3 and 500 J/(kg K) to this family and not the 7.9 and 470 often quoted for molybdenum-free 1.4301. Use 8.0 g/cm3 to estimate forged weight: a 1.4449 ring of 900 mm outside diameter, 650 mm bore and 200 mm height weighs roughly 490 kg as forged, before machining allowance.

## Corrosion resistance and PREN

PREN = %Cr + 3.3 x %Mo + 16 x %N. Applied across the 1.4449 composition window this gives 24.4 at the lean end, 26.5 in the middle and 28.6 at the rich end. Every figure in the table below is recalculated on the same mid-range basis.

| Grade | PREN (mid-range) |
| --- | --- |
| 304 / 1.4301 | 19.4 |
| 316L / 1.4404 | 25.8 |
| **1.4449** | **26.5** |
| 317L / 1.4438 | 30.9 |
| 2205 / 1.4462 | 34.5 |
| 904L / 1.4539 | 36.1 |
| 254 SMO / 1.4547 | 44.9 |

Each figure is calculated from the mid-point of that grade's own composition window. Published PREN tables often mix bases, quoting a typical mill analysis for one grade and a nominal composition for another. The same two alloys can therefore appear several points apart in one table and level in another. PREN ranks alloys against each other; it does not predict whether a given part will survive a given service. Temperature, chloride concentration, pH, crevice geometry and surface finish all move the real threshold.

**Comparison with 316L.** On a consistent basis 1.4449 and 316L are close, 26.5 against 25.8. 1.4449 does not give a large increase in pitting resistance over 316L. The difference between the two grades lies at the lean end of each composition window: 316L may be supplied at 16.5 % chromium and 2.00 % molybdenum, a PREN of 23.1, while the leanest permissible 1.4449 is 17.0 % chromium and 2.25 % molybdenum, a PREN of 24.4. Mid-range heats are comparable, but the lowest permissible composition of 1.4449 is higher. On a pressure part, that lower bound is the figure a designer works to. EN 10222-5 also sets acceptance rules written for forged sections instead of rules adapted from a plate standard. Those two factors, and not the mid-range PREN, are the technical case for selecting the grade.

1.4449 resists atmospheric corrosion and moderately oxidising and moderately reducing conditions, and performs better than a molybdenum-free austenitic in dilute sulphuric and phosphoric acid service. Against highly oxidising acids such as nitric acid, molybdenum-bearing grades are the weaker choice.

**Limits.** In warm, concentrated chloride service and in any crevice, the pitting threshold of 1.4449 is far below that of duplex or super-austenitic grades. Like all standard austenitics it is susceptible to chloride stress corrosion cracking. Onset is generally taken as near 60 C, but that figure applies to full immersion. Where chlorides concentrate by evaporation, under insulation or at a wet and dry interface, cracking is reported well below it, and some suppliers publish a threshold nearer 50 C. For hot seawater or high-chloride brine, Jiangyin Jiangnan Metal Co., Ltd. recommends 2205, 904L, 254 SMO or A182 F44 instead.

## Forged shapes and sizes in 1.4449

| Form | Size limit | Set by |
| --- | --- | --- |
| Seamless rolled rings | OD 50 to 6,000 mm | 6 m radial-axial ring mill |
| Forged rings and retaining rings | To drawing | Upset-and-punch route |
| Round, flat and square bars | Length to 6,000 mm | 6,300 t, 4,000 t and 2,000 t presses |
| Shafts and spindles | Turned length to 14,000 mm | C61160 lathe; 15 m well furnace |
| Discs, tube sheets and covers | Machined to 5,000 mm diameter | 5,000 mm vertical turning lathe |
| Flanges | ASME B16.5, B16.47, API 6A or drawing | Press and ring mill |
| Sleeves, bushings, hollow sections | Bored to 1,600 x 10,000 mm | CNC deep-hole drilling machine |
| Valve bodies, bonnets, stems, seat rings | To drawing | Near-net forged, proof or finish machined |
| Single-piece weight | 10 kg to 30,000 kg | 60 t maximum heat size; 6,300 t press |

Minimum order at Jiangyin Jiangnan Metal Co., Ltd. is 10 kg with no minimum piece count. Typical lead time is 20 to 60 days.

## Manufacturing route

1. **Melting and refining.** 25 t electric arc furnace, 25 t or 50 t ladle furnace, vacuum oxygen decarburisation in 30 t or 60 t units to bring carbon to the 0.035 % ceiling while holding chromium in the bath.
2. **Ingot and cogging.** Cogged down and cropped on the press. Electroslag remelting added where cleanliness or segregation control requires it.
3. **Open-die forging or ring rolling.** Worked from about 1,150 to 1,200 C, finished above 950 C, on 6,300 t, 4,000 t or 2,000 t presses or on 6 m, 3 m or 1 m radial-axial ring mills.
4. **Solution annealing.** 1,050 to 1,125 C per EN 10222-5, held to section thickness, then cooled in water or a water-based medium.
5. **Machining.** Descaling and proof machining, or finish machining to drawing.
6. **Non-destructive examination.** Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388; dye penetrant where surface indications matter.
7. **Testing and certification.** Heat chemistry, tensile, hardness, impact and any specified corrosion test, compiled into an EN 10204 3.1 or 3.2 certificate.
8. **Marking, preservation and packing.** Marked with heat number and part identification.

## Heat treatment, welding and machining

**Solution annealing:** 1,050 to 1,125 C per EN 10222-5, cooled in water or a water-based medium. The 1,020 to 1,120 C range widely quoted for this grade is the generic EN 10088-3 window for 316L-type bar, not the requirement of 1.4449's own standard; on a pressure-purpose forging, use of the wrong range is a nonconformity. The cooling rate is more critical than the peak temperature. The part must pass through roughly 450 to 850 C quickly enough that chromium carbides do not re-form. No hardening or ageing treatment exists for this steel.

**Welding:** good weldability, which is the point of the low carbon ceiling. Matching or slightly over-alloyed filler, commonly a 316L or 317L type consumable. Preheat is not required. Post-weld solution annealing is not normally needed but should be specified for aggressive chloride service.

**Hot working:** forge from about 1,150 to 1,200 C, finish above 950 C. Solution annealing after forging is mandatory.

**Machining:** 1.4449 work hardens during cutting. Use rigid setups, sharp positive-rake tooling, heavy constant feed, moderate speed and generous coolant. Do not let the tool dwell or rub.

## Testing and certification

Jiangyin Jiangnan Metal Co., Ltd. holds CCS, BV, DNV, LR and NK classification society approvals and runs its own laboratory on site.

| Discipline | Method | Standard |
| --- | --- | --- |
| Chemical analysis | Optical emission spectrometry | ASTM E415 |
| Carbon and sulphur | Infrared combustion analysis | ASTM E1019 |
| Alloy verification | Handheld PMI analyser | Positive material identification |
| Tensile | 600 kN and 300 kN universal testing machines | ASTM A370, ISO 6892 |
| Impact | Pendulum impact with low-temperature bath | ASTM A370, to -60 C |
| Hardness | Leeb hardness tester | ASTM A956, converted per ASTM E140 |
| Ultrasonic | Digital flaw detectors | EN 10228-3, SEP 1921, ASTM A388 |
| Magnetic particle | Multipurpose crack detector | ASTM E709 |
| Metallography | Microscope, mounting press, polisher | ASTM E112 grain size |

Intergranular corrosion testing to ASTM A262 or ASTM G28, pitting resistance to ASTM G48, impact below -60 C and bench hardness are placed with accredited third-party laboratories. ASTM A262 Practice E is the test most often requested on 1.4449.

EN 10204 3.1 inspection certificates are standard. EN 10204 3.2 witnessed by BV, DNV, LR, SGS, TUV or the customer's own inspector is available on request.

## Applications

- Chemical and petrochemical: pressure-vessel flanges, tube sheets, covers, nozzles, pump and valve parts in dilute sulphuric and phosphoric acid service
- Pulp and paper: digester and liquor-tank hardware, bleach-plant components, paper machine parts
- Oil and gas: valve bodies, bonnets, stems, seat rings, spools, manifold components
- Power generation: heat exchanger tube sheets, condenser components, casing flanges, feedwater hardware
- Flue gas and environmental: scrubber and absorber tower internals, stack liners, thermal oxidiser components
- Food, pharmaceutical and biochemical: process vessel flanges, agitator shafts, sleeves, fittings
- Heat exchangers and pressure vessels: solid forged discs, tube sheets and covers, proof machined for volumetric inspection

## How to order

Send the following to sales@steelforgepieces.com for a firm price within two working days:

1. Grade and governing standard, for example 1.4449 / X3CrNiMo18-12-3 to EN 10222-5
2. Dimensions or a drawing (PDF, DWG, DXF, STEP)
3. Quantity and expected repeat volume
4. Delivery condition: as forged, proof machined or finish machined
5. Heat treatment and testing requirements, including UT standard and acceptance class
6. Certification (EN 10204 3.1 or 3.2) and destination port

## Frequently asked questions

**What is 1.4449 steel?**
1.4449 is the EN material number for X3CrNiMo18-12-3, a molybdenum-bearing austenitic chromium-nickel stainless steel listed in EN 10222-5, the European standard for steel forgings for pressure purposes. It contains 17.0 to 18.2 % chromium, 11.5 to 12.5 % nickel and 2.25 to 2.75 % molybdenum, with carbon held to 0.035 % maximum and nitrogen to 0.08 % maximum, balance iron. Jiangyin Jiangnan Metal Co., Ltd. melts and open-die forges it into rings, bars, discs, flanges and shafts.

**Is 1.4449 the same as AISI 317 or UNS S31700?**
They are cross-referenced in commercial literature, but they are not the same steel. 1.4449 allows 2.25 to 2.75 % molybdenum and 17.0 to 18.2 % chromium, while ASTM A182 F317 and UNS S31700 require 3.00 to 4.00 % molybdenum and 18.0 to 20.0 % chromium. The molybdenum bands do not overlap at all and the chromium bands overlap by only 0.2 %, so material certified to one standard will not satisfy an order written against the other. Judged on composition, 1.4449 is closer to an enhanced 316L than to a 317.

**What is the difference between 1.4449, 1.4438 and 1.4439?**
Three different steels with EN numbers that differ by one digit. 1.4449 carries 2.25 to 2.75 % molybdenum. 1.4438 (317L) carries 3.00 to 4.00 % with higher nickel. 1.4439 (317LMN) carries 4.00 to 5.00 % plus 0.12 to 0.22 % nitrogen. Corrosion resistance and price rise across that sequence.

**What is the PREN of 1.4449?**
24.4 at the lean end of the composition window, 26.5 in the middle and 28.6 at the rich end. Recalculated on the same mid-range basis, 316L comes out at 25.8 and 317L at 30.9, so 1.4449 is only marginally above 316L, and far below duplex 2205 at 34.5 or 904L at 36.1. Tables that show a large 1.4449 advantage over 316L have mixed a typical mill analysis for one grade with a nominal composition for the other.

**What heat treatment is applied to 1.4449 forgings?**
Solution annealing at 1,050 to 1,125 C per EN 10222-5, held to section thickness and then cooled in water or a water-based medium. The 1,020 to 1,120 C range widely quoted for this grade is the generic EN 10088-3 window for 316L-type bar, not the requirement of 1.4449's own standard. 1.4449 cannot be hardened by heat treatment and receives no ageing cycle.

**Can 1.4449 be welded?**
Yes. The 0.035 % carbon limit is specified to resist sensitisation, so weldability is good and preheat is not required. Matching or slightly over-alloyed filler is normal practice.

**Where should 1.4449 not be used?**
Its pitting threshold falls away in warm concentrated chloride service and in tight crevices, and like all standard austenitics it is susceptible to chloride stress corrosion cracking. Onset is generally taken as near 60 C under full immersion. Where chlorides concentrate by evaporation, under insulation or at a wet and dry interface, cracking is reported well below that temperature. It is also the weaker choice in highly oxidising acids such as nitric acid.

**Which forged shapes can be made in 1.4449?**
Seamless rolled rings from 50 mm up to 6,000 mm outside diameter, forged rings, round and flat bars, shafts to 14,000 mm turned length, discs and tube sheets machined to 5,000 mm diameter, flanges, sleeves, bushings, hollow sections bored to 1,600 by 10,000 mm, and valve bodies, bonnets, stems and seat rings. Single-piece weight runs from 10 kg to 30 tonnes.

**What certificates come with 1.4449 forgings?**
EN 10204 3.1 as standard, covering heat chemistry, mechanical test results, the heat-treatment record and the NDT report. EN 10204 3.2 witnessed by BV, DNV, LR, SGS, TUV or the customer's own inspector on request.

**What is the minimum order quantity?**
10 kg, with no minimum piece count. Both single prototypes and series orders are quoted.

**What is the lead time?**
20 to 60 days from order confirmation. Standard stainless grades such as 1.4449 are at the lower end of that range.

**Who supplies 1.4449 forgings, and where are they made?**
Jiangyin Jiangnan Metal Co., Ltd., an integrated steel melting works and open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, operating since 1997.

## Data sources

Consolidated from published specifications and material listings for W.Nr. 1.4449 / X3CrNiMo18-12-3: EN 10222-5 (steel forgings for pressure purposes), EN 10088-3 and EN 10272 (bar), EN 10250-4 (open-die forgings), ASTM A182 (grade F317), EN 10204 (certification), and EN 10228-3, SEP 1921 and ASTM A388 (ultrasonic examination). Composition limits and the solution-treatment range come from EN 10222-5, this grade's only home standard. Density and specific heat follow the EN 10088-1 convention for molybdenum-bearing austenitic steels. Room-temperature mechanical figures in the 1.4449 column are published typical values, not standard-guaranteed minima. PREN figures are calculated from the mid-point of each grade's own composition window so that every grade is compared on the same basis.

This page describes material properties generally and is not a design authority. Take allowable design stresses from the applicable pressure code.

## Citation

Jiangyin Jiangnan Metal Co., Ltd. (2026). 1.4449 (X3CrNiMo18-12-3) Material Data Sheet for Open-Die Forgings. Jiangyin, Jiangsu, China. https://www.steelforgepieces.com/Stainless-Steel/1.4449.html

## Manufacturer

**Jiangyin Jiangnan Metal Co., Ltd.**
Integrated steel melting works and open-die forging factory, established 1997
No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
Telephone / WhatsApp / WeChat: +86-189-2135-9659
Email: sales@steelforgepieces.com
Website: https://www.steelforgepieces.com/
Approvals: CCS, BV, DNV, LR, NK
Business hours: Monday to Saturday, 08:00 to 17:30 China Standard Time