Guides/Comparisons
2304 vs 2205 duplex stainless steel
2304-vs-2205-duplex-stainless-steelLean duplex stainless steel 2304 and Duplex stainless steel 2205 at a glance
This page compares Lean duplex stainless steel 2304 and Duplex stainless steel 2205 using only values that carry a source, a test condition and an evidence level. Ranges run across temper, heat treatment and product form, measured at room temperature where the source says so.
- Composition: Chromium (2304 21.5 to 24.5%; 2205 22 to 23%), Nickel (2304 3 to 5.5%; 2205 4.5 to 6.5%), Molybdenum (2304 0.05 to 0.6%; 2205 3 to 3.5%), Nitrogen (2304 0.05 to 0.2%; 2205 0.14 to 0.2%).
- Yield strength: 2205 is higher (2304 at least 400 MPa; 2205 at least 450 MPa), about 1.7 times the midpoint of 2304.
- Tensile strength: the ranges overlap (2304 600 to 820 MPa; 2205 655 to 965 MPa).
- Density: the ranges overlap (2304 7.8 g/cm³; 2205 7.8 to 7.82 g/cm³).
- Young's modulus: the ranges overlap (2304 200 GPa; 2205 190 to 200 GPa).
- Thermal conductivity: 2304 is higher (2304 16 W/(m·K); 2205 14 to 15 W/(m·K)), about 1.1 times the midpoint of 2205.
- Service temperature: the ranges overlap (2304 280 to 315 °C; 2205 280 to 316 °C).
- Thermal expansion: the ranges overlap (2304 13 to 14 ppm/K; 2205 11 to 13 ppm/K).
"Higher" means the whole range is higher, not just one value. Where a value is a specified minimum, the table says "at least".
Side by side
| Property | Lean duplex stainless steel 2304 | Duplex stainless steel 2205 |
|---|---|---|
| Yield strength | at least 400 MPa | at least 450 MPa |
| Tensile strength | 600 to 820 MPa | 655 to 965 MPa |
| Density | 7.8 g/cm³ | 7.8 to 7.82 g/cm³ |
| Young's modulus | 200 GPa | 190 to 200 GPa |
| Thermal conductivity | 16 W/(m·K) | 14 to 15 W/(m·K) |
| Melting point | no data | 1,385 to 1,441 °C |
| Service temperature | 280 to 315 °C | 280 to 316 °C |
| Thermal expansion | 13 to 14 ppm/K | 11 to 13 ppm/K |
Composition
| Element | Lean duplex stainless steel 2304 | Duplex stainless steel 2205 |
|---|---|---|
| Iron | balance | balance |
| Chromium | 21.5 to 24.5% | 22 to 23% |
| Nickel | 3 to 5.5% | 4.5 to 6.5% |
| Molybdenum | 0.05 to 0.6% | 3 to 3.5% |
| Nitrogen | 0.05 to 0.2% | 0.14 to 0.2% |
| Copper | 0.05 to 0.6% | not listed |
| Carbon | up to 0.03% | up to 0.03% |
| Manganese | up to 2.5% | up to 2% |
| Silicon | up to 1% | up to 1% |
| Phosphorus | up to 0.04% | up to 0.03% |
| Sulphur | up to 0.03% | up to 0.02% |
Shares are as printed in the sources, by weight.
When to use which
| Material | Best for | Weakest at |
|---|---|---|
| Lean duplex stainless steel 2304 | Chloride-bearing process piping and heat exchangers, pulp and paper equipment, and strength-limited structures where 304 or 316 would crack or be too weak (Alleima, ATI) | Exposure above about 315 C (600 F), where 475 C embrittlement can follow (ATI); prolonged exposure above 280 C (Alleima); weld metal without an overmatched filler (ATI) |
| Duplex stainless steel 2205 | Chloride-bearing and sour service where 300-series steels crack, in welded pipe, tube, sheet and plate (ATI, Alleima) | Extended exposure at 343 to 530 C (475 C embrittlement), welds made with straight chromium filler, and sour service above 232 C (ATI, Alleima) |
Where each is used
| Material | Use |
|---|---|
| Lean duplex stainless steel 2304 | Process heat exchangers and piping where chlorides are present |
| Lean duplex stainless steel 2304 | Pulp and paper digester preheaters and evaporators |
| Lean duplex stainless steel 2304 | Oil and gas coolers, piping and flowlines on and offshore, and offshore rig tensioning systems |
| Lean duplex stainless steel 2304 | Beams and torque-transmitting shafts |
| Lean duplex stainless steel 2304 | Hydraulic tubing, also sold as PW 400 |
| Duplex stainless steel 2205 | Chemical process vessels, piping and heat exchangers |
| Duplex stainless steel 2205 | Oil and gas production tubing, flowlines and heat exchangers in sour service |
| Duplex stainless steel 2205 | Marine propellers, shafts, rudders, pumps and valves |