Physical properties
| Density | 7.8 | g/cm³ |
| Modulus E | 200 / 194 / 186 / 180 | GPa @ 20 / 100 / 200 / 300 °C |
| Thermal conductivity | 15 | W/(m·K) @ 20 °C |
| Thermal expansion | 13.0 / 13.5 / 14.0 | 10⁻⁶/K, mean 20-100 / 20-200 / 20-300 °C |
| Specific heat | 500 | J/(kg·K) @ 20 °C |
| Resistivity | 0.8 | Ω·mm²/m @ 20 °C |
Informative values: they vary with composition, condition and test method. Use the governing standard or measured mill data for pressure and heat-transfer calculations.
Values are taken from EN 1.4362 (the same alloy) and are informative.
Duplex grades are magnetic.
Chemical composition
Nominal: mid-range where both limits are given, the cap where only a maximum is, balance takes the remainder. Exact specified ranges below.
| Element | Name | Content % | |
|---|---|---|---|
| Main elements6 elements | |||
| Fe | Iron | Bal. | |
| Cr | Chromium | 21.5 – 24.5% | |
| Ni | Nickel | 3 – 5.5% | |
| Mo | Molybdenum | 0.05 – 0.6% | |
| Cu | Copper | 0.05 – 0.6% | |
| N | Nitrogen | 0.05 – 0.2% | |
| Element | Name | Content % | |
|---|---|---|---|
| Minor & residual5 elements | |||
| C | Carbon | ≤ 0.03% | |
| Mn | Manganese | ≤ 2.5% | |
| Si | Silicon | ≤ 1% | |
| P | Phosphorus | ≤ 0.04% | |
| S | Sulphur | ≤ 0.04% | |
Mechanical minima by form
Guaranteed values differ by form, size and delivery condition; quotations confirm the specification, form, size and condition.
| Form | Condition | Rm MPa | Rp0.2 MPa | A ≥ % | Other requirements and notes |
|---|---|---|---|---|---|
| Bar and forgings | |||||
| Bar and shapes | Condition A, solution heat treated | ≥ 600 (87 ksi) | ≥ 400 (58 ksi) | ≥ 25 | |
| Forgings, flanges and fittings (F68) | Solution treated at 927–1049 °C, liquid quenched | ≥ 600 (87 ksi) | ≥ 400 (58 ksi) | ≥ 25 | |
| Bars (EN 10088-3, ≤160 mm) | +AT (solution annealed) | 600 – 830 | ≥ 400 | ≥ 25 | Also specified: Hardness ≤ 260 HBW KV ≥ 100 J longitudinal. |
| Pressure forgings (EN 10222-5, ruling section ≤160 mm) | +AT (solution annealed) | 600 – 830 | ≥ 400 | ≥ 25 | Tangential/transverse A ≥ 20 %; KV ≥ 120/90 J (long./tang.). |
| Plate, sheet and strip | |||||
| Plate, sheet and strip | Solution heat treated | ≥ 600 (87 ksi) | ≥ 400 (58 ksi) | ≥ 25 | |
| Cold-rolled strip (EN 10088-2, ≤8 mm) | +AT (solution annealed) | 650 – 850 | ≥ 450 | ≥ 20 | |
| Hot-rolled plate (EN 10088-2, ≤75 mm) | +AT (solution annealed) | 630 – 800 | ≥ 450 | ≥ 25 | Hot-rolled strip (≤13.5 mm): Rm 650–850 MPa, A ≥ 20 %. KV ≥ 100/60 J (long./transv., over 10 mm). |
| Tube and pipe | |||||
| Heat-exchanger tube (OD≤25 mm) | Heat treated at 925–1050 °C, then water cooled or otherwise rapidly cooled | ≥ 690 (100 ksi) | ≥ 450 (65 ksi) | ≥ 25 | |
| Heat-exchanger tube (OD>25 mm) | Heat treated at 925–1050 °C, then water cooled or otherwise rapidly cooled | ≥ 600 (87 ksi) | ≥ 400 (58 ksi) | ≥ 25 | |
| Seamless and welded pipe | 1700–1920 °F [925–1050 °C], rapid cooling in water or by other means | ≥ 600 (87 ksi) | ≥ 400 (58 ksi) | ≥ 25 | Also specified: Hardness ≤ 290 HBW / 30 HRC H₂S service: with FPREN below 30, this grade is not in the NACE MR0175 / ISO 15156-3 duplex tables; qualification testing to the standard's annex is required first. |
| Electric-fusion-welded pipe | Class as specified on the order | ≥ 600 (87 ksi) | — | — | |
| Seamless and welded pressure tubes (EN 10216-5 / EN 10217-7, wall ≤30 mm) | +AT (solution annealed) | 600 – 820 | ≥ 400 | ≥ 25 | KV ≥ 120/90 J (long./transv.), at −40 °C ≥ 40 J transverse. |
Where this grade is recommended
Matched in 2 service conditions; ranks and scores computed from the condition-scoring matrix.
| Service condition | Industry | Temperature | Rank | Score |
|---|---|---|---|---|
| Ballast & tank systems | Marine & Offshore | ≤ 40 °C | 8 / 10 | 85 |
| Separators & heat-exchanger internals | Oil & Gas | 120 – 250 °C | 5 / 10 | 83 |
Designations & equivalents
| W.Nr. (Germany) | 1.4362 |
| EN designation | X2CrNiN23-4 |
| Trade name(s) | 2304 / SAF 2304 / UR35N |
| ASTM / AISI | A240 / A276 / A484 / A789 / A790 / A928 |
Cross-references are common near-equivalents for search and shortlisting; substitution across standards requires clause-by-clause verification. All grades in one cross-reference table →
Applicable standards
13 specifications. Name the standard and its edition on the order.
Guaranteed values and required tests differ between specifications — see Mechanical minima by form for the figures per form.
Frequently asked questions
What is 2304 Lean Duplex · UNS S32304?
2304 Lean Duplex · UNS S32304 — Duplex stainless steel. Molybdenum-free lean duplex — tanks, bridges and moderate-corrosion structures
What is the maximum service temperature of S32304?
Typically about 250 °C; the practical limit depends on media, stress and design life — acceptance per the governing standard.
What is the tensile strength of S32304?
The specified minimum tensile strength is 600 MPa for the main product form. Minima for other forms and sizes are listed under "Mechanical minima by form" on this page.
Which standards cover S32304?
ASTM A240/A240M, ASTM A276/A276M, ASTM A484/A484M, ASTM A789/A789M, ASTM A790/A790M, ASTM A928/A928M, ASTM A182/A182M, ASTM A1084, EN 10088-2 (sheet, plate, strip), EN 10088-3 (bar, rod, wire, sections), EN 10216-5 (seamless pressure tubes), EN 10217-7 (welded pressure tubes), EN 10222-5 (forgings for pressure purposes)
Where is S32304 typically used?
Ballast & tank systems (Marine & Offshore); Separators & heat-exchanger internals (Oil & Gas)
In which forms is S32304 available?
Tube, plate, strip, bar, forgings, wire and other forms — sizes and delivery condition confirmed per order, with EN 10204 3.1 / 3.2 certification.
Same series
Download PDF datasheet
This grade’s datasheet as an A4 PDF — for filing, printing or forwarding to colleagues.
Download PDF datasheetSupply & enquiry
Tube & pipeφ1 – 219 × 0.25 – 25 mm
Plate4.76 – 80 mm
Barφ8 – 300 mm
Wire & filler metalsφ0.01 – 8 mmFor this grade we can supply, against your service conditions:
- Tube, plate, strip, bar, forgings, wire and more — with size range and lead time
- Chemistry and mechanical test report (EN 10204 3.1 / 3.2)
- Like-for-like alternatives and selection advice
- Applicable standards and inspection scope
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