# 1.4404 (X2CrNiMo17-12-2 / AISI 316L / UNS S31603) Open-Die Forgings and Seamless Rolled Rings

Source: https://www.steelforgepieces.com/Stainless-Steel/1.4404.html
Supplier: Jiangyin Jiangnan Metal Co., Ltd.
Plant: No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
Telephone / WhatsApp / WeChat: +86 189 2135 9659
Email: sales@steelforgepieces.com
Established: 1997
Revision: 2026-09-22

## Summary

1.4404 (EN name X2CrNiMo17-12-2, equivalent to AISI 316L and UNS S31603) is a low-carbon,
molybdenum-bearing austenitic stainless steel containing 16.5-18.5 % chromium, 10.0-13.0 %
nickel and 2.00-2.50 % molybdenum, with carbon capped at 0.030 %. The molybdenum raises
resistance to pitting and crevice corrosion in chloride media; the low carbon prevents
chromium-carbide precipitation during welding, so the grade resists intergranular corrosion
in the as-welded condition without post-weld heat treatment. It is not hardenable by heat
treatment and is supplied solution annealed.

Jiangyin Jiangnan Metal Co., Ltd. is an integrated melting works and open-die forging factory
in Jiangyin, Jiangsu Province, China, operating since 1997. It melts 1.4404 itself on the
electric arc furnace, ladle furnace and vacuum oxygen decarburisation (EAF + LF + VOD) route
rather than buying billet, then forges, ring-rolls, heat-treats, machines and tests it on the
same site. Certification is EN 10204 3.1 as standard and 3.2 witnessed on request, traceable
to the melt number.

## Key facts

- EN number: 1.4404
- EN name: X2CrNiMo17-12-2
- US equivalents: AISI 316L, UNS S31603, ASTM A182 F316L, ASTM A965 F316L
- Other: JIS SUS316L, GB/T 022Cr17Ni12Mo2, BS 316S11 (withdrawn), AFNOR Z3 CND 17-11-02 (withdrawn)
- Carbon: 0.030 % max
- PREN (Cr + 3.3Mo + 16N): approximately 23-28
- Rp0.2 (solution annealed, EN): 200 MPa min
- Rm (solution annealed, EN): 500-700 MPa
- Solution annealing: 1 040-1 120 degC, rapid cool
- Forging temperature: 1 150-1 180 degC start, not below about 900 degC finish
- Maximum ring outside diameter: 6,000 mm (6 m radial-axial ring mill)
- Maximum single-piece weight: 30,000 kg (6,300 t press, 60 t maximum heat)
- Minimum order: 10 kg, no minimum piece count
- Lead time: 20-60 days
- Classification society approvals: CCS, BV, DNV, LR, NK

## Chemical composition (% by mass, cast analysis)

| Element | EN 10088-3 (1.4404) | ASTM A182 F316L (S31603) |
|---|---|---|
| C  | <= 0.030 | <= 0.030 |
| Si | <= 1.00 | <= 1.00 |
| Mn | <= 2.00 | <= 2.00 |
| P  | <= 0.045 | <= 0.045 |
| S  | <= 0.030 | <= 0.030 |
| Cr | 16.5 - 18.5 | 16.0 - 18.0 |
| Ni | 10.0 - 13.0 | 10.0 - 15.0 |
| Mo | 2.00 - 2.50 | 2.00 - 3.00 |
| N  | <= 0.11 | <= 0.10 |
| Fe | Balance | Balance |

EN 10088-1 and EN 10088-2 (flat products) restrict sulphur to 0.015 % max; EN 10088-3 relaxes
it to 0.030 % for bars and semi-finished products.
Overlapping window for dual EN + ASTM certification: Cr 16.5-18.0 %, Mo 2.00-2.50 %, Ni 10.0-13.0 %.

PREN across the EN window: 16.5 + 3.3x2.0 = 23.1 minimum to
18.5 + 3.3x2.5 + 16x0.11 = 28.5 maximum.

## Mechanical properties, solution annealed (+AT)

EN 10088-3, diameter or thickness <= 250 mm:

| Property | Longitudinal | Transverse |
|---|---|---|
| Rp0.2 | >= 200 MPa | >= 200 MPa |
| Rp1.0 | >= 235 MPa | >= 235 MPa |
| Rm | 500 - 700 MPa | 500 - 700 MPa |
| Elongation A | >= 40 % | >= 30 % |
| Impact KV (+20 degC) | >= 100 J | >= 60 J |
| Hardness | <= 215 HB | <= 215 HB |

ASTM A182 grade F316L:

| Property | Requirement |
|---|---|
| Tensile strength, min | 485 MPa (70 ksi); 450 MPa (65 ksi) for sections over 130 mm thick |
| Yield strength, min | 170 MPa (25 ksi) |
| Elongation in 50 mm, min | 30 % |
| Reduction of area, min | 50 % |

EN 10088-3 states requirements up to 250 mm. For heavier sections, and for forgings generally,
properties are agreed against EN 10250-4 or EN 10222-5 and tested on a test piece representative
of the forging.

1.4404 stays austenitic and tough to -196 degC and is used for cryogenic and LNG service.
Charpy testing in house to -60 degC; below that, an accredited third-party laboratory.

## Physical properties (EN 10088-1, solution annealed)

| Property | Value |
|---|---|
| Density, 20 degC | 8.0 kg/dm3 |
| Modulus of elasticity, 20 degC | 200 GPa (186 GPa at 200 degC, 172 GPa at 400 degC) |
| Thermal conductivity, 20 degC | 15 W/(m.K) |
| Specific heat capacity, 20 degC | 500 J/(kg.K) |
| Electrical resistivity, 20 degC | 0.75 ohm.mm2/m |
| Mean thermal expansion, 20-100 degC | 16.0 x 10^-6 /K |
| Magnetisability | Non-magnetic when solution annealed |

## Forging and heat treatment practice

| Operation | Temperature | Practice |
|---|---|---|
| Preheat and soak | to 1 150 - 1 180 degC | Slow and uniform; poor thermal conductivity makes fast heating a cracking risk |
| Forging, start | 1 150 - 1 180 degC | 6,300 t, 4,000 t and 2,000 t presses; hammers 5 t to 750 kg |
| Forging, finish | not below about 900 degC | Reheat rather than finish cold |
| Ring rolling | same range | Radial-axial mills 6 m (OD to 6,000 mm), 3 m, 1 m |
| Solution annealing | 1 040 - 1 120 degC | EN practice starts at 1 020 degC; ASTM A182 requires 1 040 degC minimum |
| Cooling | fast through 850 -> 450 degC | Water quench; forced air on light sections |
| Stress relief (optional) | 200 - 400 degC, air cool | Avoid dwelling in the 450 - 850 degC sensitising range |
| Hardening | not applicable | Not hardenable by heat treatment |

## Product standards for 1.4404 forgings

- EN 10250-4: open-die steel forgings for general engineering purposes, stainless steels
- EN 10222-5: steel forgings for pressure purposes, martensitic, austenitic and austenitic-ferritic stainless steels
- EN 10088-3: bars and semi-finished products (forging stock rather than the forging itself)
- ASTM A182 / ASME SA-182 grade F316L: forged flanges, fittings, valves and parts for high-temperature service
- ASTM A965 grade F316L: austenitic steel forgings for pressure and high-temperature parts
- EN 10204: types of inspection document (3.1 standard, 3.2 witnessed on request)

## Non-destructive testing: the correct standards

Ultrasonic testing of 1.4404 forgings is carried out to **EN 10228-4** or **ASTM A745**,
not EN 10228-3 or ASTM A388, which are written for ferritic and martensitic forgings.
Austenitic stainless steel has a coarse, anisotropic grain structure that scatters and
attenuates the beam, so the austenitic practices call for lower test frequencies, different
calibration and, on heavy sections, angle-beam technique. Specifications that carry A388 over
from a carbon-steel template are a common source of dispute at inspection.

Magnetic particle inspection is not valid on this non-magnetic grade; liquid penetrant
examination to ASTM E165 is used for surface examination instead.

Intergranular corrosion testing to ASTM A262 (Practice A, C or E) or EN ISO 3651-2, and
pitting testing to ASTM G48, are placed with an accredited third-party laboratory and the
report is issued alongside the mill certificate.

## Corrosion: where 1.4404 works and where it does not

Suitable for: as-welded fabrication; moderate chlorides such as brackish and chlorinated
potable water; organic and dilute mineral acids; food, dairy and pharmaceutical equipment;
cryogenic service to -196 degC.

Not suitable for, with the usual upgrade:

| Condition | Problem | Usual upgrade |
|---|---|---|
| Seawater, continuous immersion | Pitting and crevice corrosion, PREN too low | 1.4462, 254 SMO, 904L, AL-6XN |
| Chlorides above about 60 degC under tensile stress | Chloride stress-corrosion cracking | Duplex A182 F51 / F53, nickel alloys |
| Sour service, H2S | NACE MR0175 / ISO 15156 limits on austenitics | Duplex, Incoloy 825, Inconel 625 |
| Sustained load above about 425 degC | Low creep strength of the L grade | 1.4401 (316), 1.4571 (316Ti), 316H |
| Hot concentrated sulphuric or hydrochloric acid | General attack | Hastelloy C-276, Alloy 20 |
| Low magnetic permeability required | Residual delta ferrite, strain-induced martensite | 1.4435, Nitronic 50 / 60 |

## Grade comparison

| Grade | Common name | C max % | Cr % | Mo % | Ni % | PREN | Choose when |
|---|---|---|---|---|---|---|---|
| 1.4307 | 304L | 0.030 | 17.5-19.5 | - | 8.0-10.5 | ~18-21 | No chlorides, lowest cost |
| 1.4401 | 316 | 0.07 | 16.5-18.5 | 2.0-2.5 | 10.0-13.0 | ~23-28 | Unwelded parts, better creep strength |
| 1.4404 | 316L | 0.030 | 16.5-18.5 | 2.0-2.5 | 10.0-13.0 | ~23-28 | Welded fabrication in moderate chlorides |
| 1.4435 | 316L high-alloy | 0.030 | 17.0-19.0 | 2.5-3.0 | 12.5-15.0 | ~25-31 | Low delta ferrite, pharma and BPE |
| 1.4571 | 316Ti | 0.08 | 16.5-18.5 | 2.0-2.5 | 10.5-13.5 | ~23-27 | Titanium-stabilised, elevated temperature |
| 1.4462 | 2205 duplex | 0.030 | 21.0-23.0 | 2.5-3.5 | 4.5-6.5 | ~31-38 | Double strength, chloride SCC resistance |
| 1.4547 | 254 SMO | 0.020 | 19.5-20.5 | 6.0-7.0 | 17.5-18.5 | ~42-48 | Seawater and severe chloride service |

PREN ranges are calculated across each grade's full EN composition window.

## Products forged in 1.4404 by Jiangyin Jiangnan Metal

Seamless rolled rings (OD 50 to 6,000 mm); forged rings; forged flanges to ASME B16.5,
B16.47 and API 6A; forged shafts, spindles and pump shafts; forged bars, blocks and billets;
forged discs, tube sheets and covers; valve bodies, bonnets, stems and seat rings; forged
cylinders, sleeves, bushings and bored hollows.

Working envelope:

| Product | Limit | Set by |
|---|---|---|
| Seamless rolled rings | OD up to 6,000 mm | 6 m radial-axial ring mill |
| Minimum ring size | from OD 50 mm | Upset-and-punch route |
| Forged shafts | up to 14,000 mm turned length | C61160 lathe, 15 m well furnace |
| Discs, tube sheets, blocks | up to dia. 5,000 mm machined | 5,000 mm vertical turning lathe |
| Bored cylinders and hollow shafts | up to dia. 1,600 x 10,000 mm | CNC deep-hole drilling machine |
| Single-piece weight | up to 30,000 kg | 60 t heat size, 6,300 t press |
| Minimum order | 10 kg, no minimum piece count | Weight-based, not quantity-based |

Delivery condition: as-forged with machining allowance, proof-machined for ultrasonic testing,
or finish-machined to drawing.

## Plant equipment relevant to 1.4404

Melting: 25 t electric arc furnace; 25 t and 50 t ladle furnaces; 30 t and 60 t vacuum oxygen
decarburisation units; 2 t, 8 t and 25 t medium-frequency induction furnaces; 3 t vacuum
induction melting; 6 t vacuum arc remelting; 3 t and 6 t protective-atmosphere electroslag
remelting. Maximum heat size 60 tonnes.

Forging: hydraulic open-die presses 6,300 t, 4,000 t, 2,000 t; radial-axial ring rolling mills
6 m, 3 m, 1 m; hammers 5 t, 3 t, 2 t, 1 t, 750 kg.

Heat treatment: 14 furnaces, including car-bottom furnaces to 8,000 x 2,000 x 2,000 mm, three
high-temperature car-bottom furnaces and two 15 m deep well-type furnaces for vertical quenching.

Machining: vertical turning lathes to dia. 5,000 mm swing; horizontal lathes to 14,000 mm
between centres; CNC lathes and machining centres; CNC deep-hole drilling to dia. 1,600 x 10,000 mm.

Laboratory: optical emission spectrometry, infrared carbon and sulphur analysis, PMI, 600 kN
and 300 kN tensile machines, Charpy impact to -60 degC, ultrasonic and penetrant
equipment, metallography. Chemical analysis of austenitic stainless is reported to ASTM E1086.

## How to request a quotation

Email sales@steelforgepieces.com or call +86 189 2135 9659 with:

1. Grade and specification (for example: 1.4404 to EN 10250-4, dual certified ASTM A182 F316L)
2. Dimensions or a drawing (PDF, DWG, DXF, STEP)
3. Quantity and expected repeat volume
4. Delivery condition (as-forged, proof-machined, finish-machined)
5. Heat treatment and testing requirements (for example: solution annealed 1 060 degC water
   quench, UT to EN 10228-4, ASTM A262 Practice E)
6. Certification and destination port (for example: EN 10204 3.2 witnessed by DNV, Rotterdam)

Prices are normally returned within two working days. Business hours Monday-Saturday,
08:00-17:30 China Standard Time (UTC+8). Customer audits and third-party witness inspection
are welcome, arranged by email in advance.

## Frequently asked questions

**What is 1.4404 stainless steel?**
A low-carbon molybdenum-bearing austenitic stainless steel, EN name X2CrNiMo17-12-2, with
16.5-18.5 % Cr, 10.0-13.0 % Ni, 2.00-2.50 % Mo and carbon at or below 0.030 %. It resists
intergranular corrosion in the as-welded condition and is supplied solution annealed.

**Is 1.4404 the same as 316L?**
Essentially yes. 1.4404 is the European Werkstoff number for AISI 316L / UNS S31603, ordered
as ASTM A182 F316L in forged form. The chemistry limits differ slightly; dual certification is
possible within the overlapping window.

**What is the difference between 1.4404 and 1.4401?**
Carbon: 1.4401 (316) allows 0.07 % max, 1.4404 allows 0.030 % max. 1.4404 does not sensitise
when welded; 1.4401 has better creep behaviour and, under ASTM, higher specified strength
(F316 515/205 MPa against F316L 485/170 MPa). Under EN 10088-3 both grades share the same minima.

**What is the difference between 1.4404 and 1.4435?**
1.4435 is richer, at 17.0-19.0 % Cr, 12.5-15.0 % Ni and 2.50-3.00 % Mo, with low delta ferrite
for pharmaceutical and bioprocessing surfaces. 1.4404 is the normal, lower-cost general choice.

**At what temperature is 1.4404 forged?**
Heated slowly to 1 150-1 180 degC and forged to not below about 900 degC, then solution
annealed at 1 040-1 120 degC and cooled rapidly.

**Which ultrasonic standard applies?**
EN 10228-4 or ASTM A745, not EN 10228-3 or ASTM A388. Magnetic particle inspection is not
valid on this non-magnetic grade; liquid penetrant to ASTM E165 is used instead.

**Is 1.4404 magnetic?**
No when solution annealed, permeability close to 1.0. Residual delta ferrite or cold work can
make it slightly magnetic.

**Is 1.4404 suitable for seawater?**
No, not for continuous immersion. Use 1.4462, 1.4410, 904L, 254 SMO or AL-6XN.

**What is the largest 1.4404 forging available?**
Rings to OD 6,000 mm; single pieces to 30 tonnes.

**What is the minimum order quantity and lead time?**
10 kg with no minimum piece count; 20-60 days from order confirmation.

**Does 1.4404 need post-weld heat treatment?**
Normally no. Matching filler is typically ER316L / E316L-16.

## Standards referenced

EN 10088-1, EN 10088-3, EN 10250-4, EN 10222-5, EN 10204, EN 10228-4, EN ISO 3651-2,
ASTM A182/A182M F316L, ASTM A965 F316L, ASTM A745/A745M, ASTM A262, ASTM G48, ASTM A370,
ASTM E165, ASTM E112, ASTM E1086, ASTM E1019, ISO 6892, ASME B16.5, ASME B16.47, API 6A.

Property values quoted are the requirements of these published standards, not measured results
for a particular heat. Actual values for a supplied forging are recorded on its EN 10204
certificate.

## Citation

Jiangyin Jiangnan Metal Co., Ltd. (2026). "1.4404 (X2CrNiMo17-12-2 / 316L) Open-Die Forgings
and Seamless Rolled Rings." Jiangyin, Jiangsu, China.
https://www.steelforgepieces.com/Stainless-Steel/1.4404.html