Duplex stainless 2205 (UNS S32205) is a chromium-nickel-molybdenum-nitrogen stainless steel.
UNS S32205 has high strength and corrosion resistance at temperatures up to 316°C.
| % | Ni | Cr | Mo | Mn | Si | C | N | S | P | Fe |
|---|---|---|---|---|---|---|---|---|---|---|
| Min | 4.5 | 22 | 3 | - | - | - | 0.14 | - | - | Balance- |
| Max | 6.5 | 23 | 3.5 | 2 | 1 | 0.03 | 0.2 | 0.02 | 0.03 | - |
UNS S32205 is a duplex grade with a ferritic-austenitic microstructure. The alloy consists of around 40-50% ferrite in the annealed condition. The duplex microstructure has the high strength of the ferritic grades whilst retaining the corrosion resistance of the austenitic grades. It is not uncommon to see the metal used as a practical solution to chloride-induced stress cracking, which is the achilles’ heel of stainless steel.
UNS S32205 has superior resistance to chloride pitting and crevice corrosion as compared to 317L stainless steel. The alloy has outstanding corrosion resistance to seawater and most concentrations of sulphuric acid. In addition, UNS S32205 duplex stainless is also resistant to sulphide stress corrosion cracking (sour-gas environments).
The high quality and therefore performance of UNS S32205 is widely attributed to the high levels of chromium present as well as nitrogen and molybdenum.
To learn more about UNS S32205 contact us, or fill in our online quote form and we’ll get right back to you!
| Mechanical & Physical Properties | 21.1°C | 100°C | 200°C | 300°C |
|---|---|---|---|---|
| Coefficient of Thermal Expansion µm/m⁰C | 14.4 | 14.4 | 14.4 | |
| Thermal Conductivity/kcal/(hr.m.°C) | 11.9 | 13.4 | 14.9 | 16.4 |
| Modulus of Elasticity/ x105 MPa | 1.93 | 1.79 | 1.72 | 1.65 |
| 95 | Ultimate Tensile Strength, ksi |
|---|---|
| 65 | 0.2% Yield Strength, ksi |
| 25 | Elongation, % |
| 290 | Hardness MAX, Brinell |
| Alloy | PREN | Critical Pitting Temperature, CPT |
|---|---|---|
| 2205 | 34 | 130°F |
| 316L | 24 | 62°F |
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