Bar and Rod
Plate and Sheet
Strip
Pipe and Tube
Wire
Welding
Powder Material
Cast Products
Forged Products
Fittings
Fastening
Round Bar:
φ2–500 mm, 1–6 m length
Flat/Square Bar:
4–100 mm thickness/width
Hex Bar:
A/F 3–100 mm
Hollow Bar:
OD 20–300 mm
Sheet:
0.3–6 mm thickness
Medium Plate:
6–25 mm thickness
Heavy Plate:
25–100 mm thickness
Standard Strip:
0.05–3 mm thick,
10–600 mm wide
Precision strip:
0.01–0.5 mm thick,
tight tolerance ±0.005 mm
Foil:
0.005–0.1 mm thick
Seamless Tube:
OD 6–450 mm,
WT 1–50 mm,
1–12 m length
Welded Tube:
OD 10–600 mm,
WT 1–20 mm
Capillary Tube:
OD 1–10 mm,
WT 0.1–2 mm
Wire Form:
Cold Drawn Wire,
Bright Wire,
Spring Wire,
Fine Wire,
Ultra-fine Wire
General Diameter:
φ0.1–10 mm
Coil Weight:
50–500 kg,
customizable tolerance
Solid Wire:
φ0.8–4.0 mm
Flux-cored Wire:
φ1.2–4.0 mm
Welding Rod:
φ2.0–5.0 mm
Powder Form:
AM 3D Printing Powder,
Spherical Powder,
Gas-atomized Powder,
Water-atomized Powder
Particle Size:
10–150 μm
Sphericity:
≥90% for AM grade
Cast Ingot:
φ200–800 mm
Precision Casting:
min wall 0.5 mm
Cast Pipe:
OD 100–600 mm,
WT 10–50 mm
Forged Bar:
Φ35–500 mm
Forged Ring:
OD 200–2000 mm
Forging Weight:
1–5000 kg
Fittings Form:
Elbow, Tee, Reducer, Flange, Cap, Outlet, Lap Joint
Size range:
1/2''–24'' (DN15–DN600)
Wall thickness:
Sch10–Sch160, STD, XS, XXS
Pressure Class:
150–2500 LB
Fastening Form:
Bolt, Nut, Screw, Stud, Washer, Pin, Rivet
Metric: M3–M64
Imperial: #4–2.5''
Length: 6–500 mm
S32304 is a molybdenum-free lean ferritic-austenitic (duplex) stainless steel, with a microstructure of roughly equal ferrite and austenite. This datasheet presents the material within the American (ASTM / ASME / UNS) standard system.
With about 23% chromium, 4% nickel and 0.10% nitrogen and no deliberate molybdenum addition, S32304 offers general corrosion resistance comparable to 316L together with yield strength roughly twice that of 304/316 austenitic grades, allowing weight savings in properly designed applications. The low nickel and high chromium contents give improved resistance to chloride stress-corrosion cracking relative to 304 and 316. It is suited to the −50 °C to +300 °C temperature range.
Typical applications include storage tanks, pressure vessels, structural and architectural components, water and wastewater treatment, pulp-and-paper equipment, and concrete reinforcement bar in aggressive environments.
| Property | Value | Unit |
|---|---|---|
| Density | 7.8 | g/cm³ |
| Melting range | 1385–1450 | °C |
| Elastic modulus | 200 | GPa |
| Coefficient of thermal expansion (20–100 °C) | 13 | µm/m·°C |
| Thermal conductivity (20 °C) | 15 | W/m·K |
| Maximum operating temperature | ~300 | °C |
| Structure | Ferritic-austenitic (duplex) | — |
| Element | Symbol | Min % | Max % | Role in Alloy |
|---|---|---|---|---|
| Iron | Fe | Balance | — | Base element |
| Chromium | Cr | 21.5 | 24.5 | Ferrite former; corrosion resistance |
| Nickel | Ni | 3.0 | 5.5 | Austenite former; phase balance |
| Molybdenum | Mo | 0.05 | 0.60 | Residual (molybdenum-free grade) |
| Copper | Cu | 0.05 | 0.60 | Residual |
| Nitrogen | N | 0.05 | 0.20 | Austenite former; strength; pitting |
| Manganese | Mn | — | 2.50 | Deoxidiser |
| Silicon | Si | — | 1.00 | Deoxidiser |
| Carbon | C | — | 0.030 | Low (intergranular resistance) |
| Phosphorus | P | — | 0.040 | Residual impurity |
| Sulphur | S | — | 0.030 | Residual impurity |
Solution-annealed condition, per ASTM A240 for UNS S32304.
| Condition | Property | Value |
|---|---|---|
| Solution-annealed | Tensile strength (UTS) | ≥600 MPa |
| Solution-annealed | 0.2% yield strength | ≥400 MPa |
| Solution-annealed | Elongation at break | ≥25 % |
| Solution-annealed | Hardness | ≤290 HB |
| — | Elastic modulus | 200 GPa |
Confirm against the mill test report.
| Environment | Performance | Notes |
|---|---|---|
| General corrosion | Very Good | Comparable to 316L |
| Chloride stress-corrosion cracking | Very Good | Superior to 304 / 316 (ferrite phase) |
| Pitting and crevice corrosion | Good | PREN ~24–26 |
| Erosion / corrosion fatigue | Very Good | High strength |
| Seawater / sour (H₂S) | Limited | Not recommended for aggressive chlorides / sour service |
Not hardenable by heat treatment; properties are set by solution annealing and phase balance.
Solution Anneal Approximately 1020–1100 °C followed by rapid cooling (water quench) to retain the balanced ferrite-austenite structure and avoid embrittling intermetallic phases. Avoid prolonged exposure in the 350–950 °C range (sigma-phase / 475 °C embrittlement); do not use above ~300 °C in service.
Good weldability with correct procedures; use a matching lean-duplex or 23 7 N-type filler and control heat input to maintain phase balance.
| Welding Process | Applicability | Filler / Consumable |
|---|---|---|
| GTAW / TIG | Good | Lean-duplex (23 7 N type) or ER2209 |
| GMAW / MIG | Good | Lean-duplex or ER2209 |
| SMAW / stick | Good | Matching duplex electrode |
No preheat; control interpass temperature and heat input to maintain phase balance.
Machining Guidelines
| Parameter | Recommendation |
|---|---|
| Machinability | Good for a duplex; rigid setup, carbide tools, moderate speeds |
| Work hardening | Significant; positive feeds, avoid dwelling |
| Coolant | Ample flood coolant |
Forming Processes
| Process | Notes |
|---|---|
| Cold forming | Higher forces than austenitics (high duplex strength) |
| Hot forming | ~1150–950 °C; solution anneal + quench afterward |
| Industry | Typical Components | Key Requirements |
|---|---|---|
| Storage / containment | Tanks, pressure vessels, silos | Strength + SCC resistance, low cost |
| Construction | Structural sections, rebar, facades | High strength-to-weight |
| Water / municipal | Wastewater treatment, water tanks | Chloride resistance |
| Pulp & paper | Process equipment | Chloride + caustic resistance |
| Product Form | ASTM Standard | ASME Code |
|---|---|---|
| Plate, sheet and strip | ASTM A240 | ASME SA-240 |
| Bar and shapes | ASTM A276 / A479 | ASME SA-479 |
| Seamless / welded tube | ASTM A789 | ASME SA-789 |
| Seamless / welded pipe | ASTM A790 | ASME SA-790 |
| Fittings | ASTM A815 | ASME SA-815 |
| Sour service | NACE MR0175 / ISO 15156 | — |
Molybdenum-free lean ferritic-austenitic (duplex) stainless steel. UNS S32304.
| UNS | Cr % | Ni % | Mo % | N % | Best Used For |
|---|---|---|---|---|---|
| S32304 | 21.5–24.5 | 3.0–5.5 | 0.05–0.60 | 0.05–0.20 | Lean Mo-free duplex; 316L substitute |
| S32101 | 21–22 | 1.35–1.70 | 0.10–0.80 | 0.20–0.25 | Lean low-Ni duplex |
| S31803 | 21–23 | 4.5–6.5 | 2.5–3.5 | 0.08–0.20 | Standard duplex |
| S30403 | 18–20 | 8–12 | — | — | Austenitic general service |
| S31603 | 16–18 | 10–14 | 2.0–3.0 | — | Austenitic, chloride service |
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