Duplex 2205 (UNS S31803 / S32205)
Duplex 2205 (UNS S31803 / S32205) — Roughly twice the strength of 316L with excellent chloride stress-corrosion resistance.
| UNS number | S31803 / S32205 |
| Material family | Duplex stainless |
| Product specifications | A182 F51 / F60, A815, A790 |
| Density (typical) | 7.8 g/cm³ (7800 kg/m³) |
| Weight of 6" Sch 40 pipe | 28.08 kg/m |
Specifications by product form
One alloy is ordered under different ASTM/ASME numbers depending on form: forged flanges and fittings, wrought buttweld fittings, and pipe or tube. For Duplex 2205 the usual specifications are A182 F51 / F60, A815, A790. Quote both the specification and the UNS number on purchase orders to avoid ambiguity.
Chemical and mechanical limits differ between these specifications — always check the edition of the standard named on your order and the mill test certificate.
Chemical composition & mechanical properties
| Property | Duplex S31803 | Duplex 2205 (S32205) |
|---|---|---|
| Family | Duplex stainless | Duplex stainless |
| UNS | S31803 | S32205 |
| EN / W.Nr | 1.4462 X2CrNiMoN22-5-3 | 1.4462 X2CrNiMoN22-5-3 |
| Basis spec | ASTM A240 | ASTM A240 |
| Density g/cm³ | 7.8 | 7.8 |
| Chemical composition, % | ||
| C | 0.030 | 0.030 |
| Mn | 2.00 | 2.00 |
| P | 0.030 | 0.030 |
| S | 0.020 | 0.020 |
| Si | 1.00 | 1.00 |
| Cr | 21.0–23.0 | 22.0–23.0 |
| Ni | 4.5–6.5 | 4.5–6.5 |
| Mo | 2.5–3.5 | 3.0–3.5 |
| N | 0.08–0.20 | 0.14–0.20 |
| Mechanical properties (min) | ||
| Tensile strength | 620 MPa (90 ksi) | 655 MPa (95 ksi) |
| Yield strength (0.2%) | 450 MPa (65 ksi) | 450 MPa (65 ksi) |
| Elongation | 25% | 25% |
| Hardness (max) | 293 HB | 293 HB |
| PREN (min, from spec) | 30.5 | 34.1 |
Single values are maximums; ranges are min–max; "bal" = balance. Limits are typical of the basis specification for that product form — forgings, pipe and fittings specifications differ slightly. Always check the exact specification, edition and the mill test certificate.
Frequently asked questions
What is the UNS number of Duplex 2205?
S31803 / S32205.
Which ASTM specifications cover Duplex 2205?
A182 F51 / F60, A815, A790.
What is the density of Duplex 2205?
About 7.8 g/cm³ (7800 kg/m³), used for weight calculations.
Last updated 2026-11-02