Lean Duplex 2304 · UNS S32304 · W. Nr. 1.4362
Lean Duplex 2304 (S32304): composition, properties, fittings and flanges
Lean Duplex 2304 (S32304, W. Nr. 1.4362) is Lean duplex stainless steel (23 % Cr, 4 % Ni). Lean Duplex 2304 is specified at Chromium 21.5 - 24.5, Nickel 3.00 - 5.50, Molybdenum 0.05 - 0.60. 2304 is the entry-level duplex: roughly twice the yield strength of 316L with better stress corrosion cracking resistance, but with so…
- UNS
- S32304
- W. Nr.
- 1.4362
- Density
- 7.80 g/cm³ (0.282 lb/in³)
- Key strength
- 600 MPa / 87 ksi
Identification and standards
| Short form | Lean Duplex 2304 · UNS S32304 · W. Nr. 1.4362 |
|---|---|
| Classification | Lean duplex stainless steel (23 % Cr, 4 % Ni) |
| UNS | S32304 |
| Werkstoff number | 1.4362 |
| Material family | Stainless Steel |
Chemical composition
| Element | Composition (wt %) | Why it is there |
|---|---|---|
| Chromium (Cr) | 21.5 - 24.5 | Pitting and oxidation resistance |
| Nickel (Ni) | 3.00 - 5.50 | Austenite balance |
| Molybdenum (Mo) | 0.05 - 0.60 | Pitting resistance |
| Nitrogen (N) | 0.05 - 0.20 | Strength and pitting resistance |
| Manganese (Mn) | 2.50 max | - |
| Silicon (Si) | 1.00 max | - |
| Carbon (C) | 0.030 max | Sensitisation control |
| Iron (Fe) | Balance | Matrix |
Note Single figures are maximum limits unless shown as a range. Always confirm against the heat-specific EN 10204 3.1 certificate supplied with your order.
Mechanical properties
| Tensile strength, min (annealed) | 600 MPa / 87 ksi |
|---|---|
| 0.2 % yield strength, min | 400 MPa / 58 ksi |
| Elongation in 2 in, min | 25 % |
| Typical hardness, annealed | 200 - 250 HB |
| PREN, typical | About 25 |
Warning Values depend on product form, section thickness and heat treatment. Larger sections generally achieve lower strength than thin product; always design against the applicable code allowable stress rather than these figures.
Physical properties
| Density | 7.80 g/cm³ (0.282 lb/in³) |
|---|---|
| Melting range | 1400 - 1460 °C (2550 - 2660 °F) |
| Modulus of elasticity | 200 GPa (29.0 x 10⁶ psi) |
| Thermal conductivity at 20 °C | 15.0 W/m·K |
| Mean coefficient of thermal expansion, 20-100 °C | 13.0 µm/m·°C |
| Specific heat capacity | 490 J/kg·K |
Specifications by product form
| Forgings & flanges | ASTM A182 F51 / F53 family or A182 UNS S32304 |
|---|---|
| Butt weld fittings | ASTM A815 UNS S32304 |
| Seamless pipe & tube | ASTM A790 / A789 UNS S32304 |
| Plate / sheet / strip | ASTM A240 UNS S32304 |
| Bar / rod | ASTM A276 / A479 |
| Welding consumables | ER2209 |
| UNS / EN / China | UNS S32304 · W. Nr. 1.4362 |
Product forms available
Hangbo supplies this grade in the following forms. Sizes outside the listed range can often be produced to order.
- Forged flanges blanks and finished flanges to ASME B16.5, B16.47 Series A/B and B16.36
- Butt weld elbows, tees, reducers, caps and stub ends to ASME B16.9 and MSS SP-43
- Seamless pipe and tube to the applicable ASTM / ASME pipe specification
- Forged rings, discs and hubs machined to your drawing
Typical applications
- Water, desalination and brine handling piping
- Pulp and paper digester and bleach plant equipment
- Storage tanks and pressure vessels
- Structural and architecture work needing higher strength than 316L
Welding, forming and machining
- Welding
- Weld with ER2209 filler. Duplex weld metal needs enough heat input control to keep roughly equal ferrite and austenite: too cold gives excess ferrite, too hot gives sigma phase.
- Heat treatment
- Solution anneal at 980 - 1050 °C and water quench.
- Hot and cold forming
- Hot work in the range stated by the mill for this grade, then re-solution or re-age before final machining so that the delivered condition matches the certificate.
- Machining
- Machine with sharp carbide or high-speed steel tooling, positive rake, constant feed and ample coolant. Never dwell - the surface work-hardens quickly.
Buy Lean Duplex 2304 from Hangbo
Material is supplied with full heat-number traceability, solution annealing or ageing performed under calibrated furnace control, and an EN 10204 3.1 certificate covering chemical analysis, mechanical properties, heat treatment records and the agreed NDT scope. Positive material identification and third party inspection and test reports from SGS are available for critical service.