Duplex & Super Duplex Steels
S31803/S32205 • 1.4462
- Application
Standard duplex stainless like S32205 or S31803, is a mixed microstructure of austenite and ferrite (50/50) which has improved strength over ferritic and austenitic steel grades.
Due to its excellent corrosion properties, duplex stainless is a highly suitable Industries predominantly using this grade material for service in environments containing chlorides and hydrogen sulphide. The material is suitable for use in production tubing and flowlines for the extraction of oil and gas from sour wells, in refineries and in process solutions contaminated with chlorides. duplex stainless is particularly suitable for heat exchangers where chloride-bearing water or brackish water is used as a cooling medium. The steel is also suitable for use in dilute sulphuric acid solutions and for handling, organic acids, e.g. acetic acid and mixtures. The high strength of duplex stainless makes the material an attractive alternative
to the austenitic steels in structures subjected to heavy loads. The good mechanical and corrosion properties make duplex stainless an economical choice in many applications by reducing the life cycle cost of equipment.
- Typical manufacturing specifications
ASTM A789, ASTM A790
Also individual customer specifications.
- Industries predominantly using this grade
Process engineering, Control lines, Heat Exchangers, Fuel rail etc.
Technical Data
Chemical composition(% by Weight)
Element | C | Mn | P | S | Si | Ni | Cr | Mo | N |
|---|---|---|---|---|---|---|---|---|---|
Minimum | - | - | - | - | - | 4.5 | 22.0 | 3.0 | 0.14 |
Maximum | 0.030 | 2.00 | 0.030 | 0.020 | 1.00 | 6.5 | 23.0 | 3.5 | 0.2 |
Aiming | 0.013 | 0.8 | 0.03 | 0.002 | 0.4 | 5.4 | 22.5 | 3.1 | 0.17 |
Mechanical Properties
| Specifications(Tubing, Annealed) | Actual data | |||
|---|---|---|---|---|
|
Tensile Rm |
95 |
ksi (min.) |
101 ~ 123 |
ksi |
|
Tensile Rm |
655 |
MPa (min.) |
700 ~ 850 |
MPa |
|
Yield (R.p. 0.2%) |
70 |
ksi (min.) |
79 ~ 98 |
ksi |
|
Yield (R.p. 0.2%) |
485 |
MPa (min.) |
550 ~ 680 |
MPa |
|
Elongation |
25 |
% (min.) |
30 ~ 38 |
% |