- All
- Product Name
- Product Keyword
- Product Model
- Product Summary
- Product Description
- Multi Field Search
 |
The alloy consists of around 40-50% ferrite in the annealed condition. It 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, it is also resistant to sulphide stress corrosion cracking (sour-gas environments).
Carbon (C) | 0.0 - 0.03 |
Chromium (Cr) | 21.00 - 23.00 |
Manganese (Mn) | 2.00 max |
Silicon (Si) | 1.00 max |
Phosphorous (P) | 0.0 - 0.03 |
Sulphur (S) | 0.0 - 0.02 |
Nickel (Ni) | 4.50 - 6.50 |
Nitrogen (N) | 0.08 - 0.20 |
Molybdenum (Mo) | 2.50 - 3.50 |
Iron (Fe) | Balance |
Mechanical properties | Tensile, min, ksi[MPa] | Yield, min, ksi[MPa] | Elongation, %(min) | Hardness, HB（max） |
S31803 | 90 [620] | 65 [450] | 25 | 290 |
STANDARD | WERKSTOFF NR. | UNS | EN |
Duplex S31803 | 1.4462 | S31803 | X2CrNiMoN22-5-3 |
Duplex stainless steel S31803 ASTM Specifications
Pipe | Tube | Sheet/Plate | Bar /Rod | Forging /Flange | BW Fittings |
ASTM A790 | ASTM A789 | ASTM A240 | ASTM A276/A479 | ASTM A182 | ASTM A815 |
Corrosion Resistance：
Duplex stainless steels are extremely corrosion resistant. They have high resistance to intergranular corrosion. Even in chloride and sulphide environments, duplex stainless steels exhibit very high resistance to stress corrosion cracking. While the super duplex grades are even more resistant to corrosion.
Heat Resistance：
The high chromium content of duplex stainless steels that protects against corrosion, causes embrittlement at temperatures over about 300°C. At low temperatures duplex stainless steels have better ductility than the ferritic and martensitic grades. Duplex grades can readily be used down to at least -50°C.
Heat Treatment:
The solution treatment temperature is 1040-1100°C, and it must be quenched after heat treatment. The cooling rate should be as fast as possible, and the time of exposure to the brittle temperature range (475°C brittle temperature range, σ brittle temperature range) must be shortened.
Pickling:
Pickling uses a mixture of nitric and hydrofluoric acids. Since the scale of S31803 is slightly more difficult to remove compared to SUS 304, it may be more effective to perform a short alkali immersion before pickling or, if possible, shot peening.
Duplex stainless steel S31803 Application:
Seawater systems
Oil field piping
Chemical process vessels, piping, and heat exchangers
FGD scrubber systems
Pulp mill digesters, bleach washers
Food process equipment
