Duplex Stainless Steels

Duplex Stainless Steels are;

Duplex (Austenitic-Ferritic) or 22% Chrome St/St, also with

Nickel (Ni) 5%
Molybdenum (Mo) 3%
Sometimes Copper (Cu) 1%

Fe Cr22 Ni5 Mo3

UNS J92205

Also known as:

UNS S31803, SAF2205, Alloy 2205, DIN 1.4462
4A (ASTM 891)

Typical Properties

Tensile 620 min N/mm2
Yield 415 min N/mm2
Elongation 20%
Hardness 185 HB typ
Density 7.8 g/cm3
P/T ratings, typically B16.34 group 2.8 =20 bar class 150 (UNS S32570)

Corrosion Properties

Good for seawater service
Especially good for:
- General corrosion
- Erosion /corrosion
- Stress corrosion cracking
- Corrosion fatigue
Poor fouling resistance