Duplex 2205 is a two-phase, ferritic, austenitic 22% chromium, 3% molybdenum, 5 to 6% nickel alloyed stainless steel. It is the most widely used duplex stainless steel grade and is characterized by high yield strength, double that of the standard austenitic stainless steel grades. It also demonstrates good fatigue strength, as well as outstanding resistance to stress corrosion cracking, crevice, pitting, erosion, and general corrosion in severe environments.
Chemical Properties:
| | C | Mn | Si | P | S | Cr | Mo | Ni | N |
2205
(S31803) | 0.03
max | 2.0
max | 1.0
max | 0.03
max | 0.02
max | min: 21.0
max: 23.0 | min: 2.5
max: 3.5 | min: 4.5
max: 6.5 | min: 0.08
max: 0.20 |
2205
(S32205) | 0.03
max | 2.0
max | 1.0
max | 0.03
max | 0.02
max | min: 22.0
max: 23.0 | min: 3.0
max: 3.5 | min: 4.5
max: 6.5 | min: 0.14
max: 0.20 |
| | C | Mn | Si | P | S | Cr | Mo | Ni | N |
Mechanical Properties:
| Grade | Tensile Strength
ksi (min) | Yield Strength
0.2% ksi (min) | Elongation % | Hardness (HB) MAX |
| 2205 | 90 | 65 | 25 | 217 |
| Grade | Tensile Strength
ksi (min) | Yield Strength
0.2% ksi (min) | Elongation % | Hardness (HB) MAX |
APPLICATIONS:
- Chemical processing, transport and storage – pressure vessels, tanks, piping, and heat exchangers
- Oil and gas exploration and processing equipment – piping, tubing, and heat exchangers
- Marine and other high chloride environments
- Effluent scrubbing systems
- Pulp and paper industry – digesters, bleaching equipment, and stock-handling systems
- Cargo tanks for ships and trucks
- Food processing equipment
- Biofuels plants
STANDARDS:
- ASTM/ASME: A240 UNS S32205/S31803
- EURONORM: 1.4462 X2CrNiMoN 22.5.3
- AFNOR: Z3 CrNi 22.05 AZ
- DIN: W.Nr 1.4462
CORROSION RESISTANCE:
- Due to its high chromium, molybdenum, and nitrogen content, Duplex 2205 demonstrates superior corrosion resistant properties to 316 and 316L in most environments
- Chromium, molybdenum, and nitrogen content also provide high resistance to pitting and crevice corrosion, even in oxidizing and acidic solutions
- Resistant to chloride stress corrosion cracking and temperatures of up to about 302°F (150°C)
- The presence of ferrite provides for good performance of Duplex 2205 in caustic environments
HEAT RESISTANCE:
- Similar to other duplex stainless steels, Duplex 2205 has good oxidation resistance at high temperatures
- Subject to embrittlement when exposed to temperatures above 572°F (300°C) even when exposed for short periods of time; Duplex 2205 is therefore not recommended for use above 572°F (300°C)
