F51 DUPLEX UNS S31803 wr. 1.4462 stainless steel is an alloy with a microstructure balanced by 50% austenite and ferrite , offering high mechanical strength and good corrosion resistance. Thanks to its composition, it guarantees good resistance to chloride- induced stress corrosion cracking and can be used in aggressive environments where austenitic stainless steels would not be adequate.
This alloy is used in critical industrial applications, such as oil and gas, chemical, marine, and power generation. F51 DUPLEX S31803 can be supplied with a PREN (Pitting Resistance Equivalent) >34, which ensures high resistance to pitting corrosion.
Reference standards:
| Element | Min (%) | Max (%) |
|---|---|---|
| Chromium (Cr) | 21.0 | 23.0 |
| Nickel (Ni) | 4.5 | 6.5 |
| Molybdenum (Mo) | 2.5 | 3.5 |
| Nitrogen (N) | 0.10 | 0.22 |
| Carbon (C) | – | 0.03 |
| Manganese (Mn) | – | 2.00 |
| Silicon (Si) | – | 1.00 |
| Sulfur (S) | – | 0.015 |
| Phosphorus (P) | – | 0.035 |
| Property | Value |
|---|---|
| Tensile Strength (UTS) | 650 – 880 MPa (94 – 128 ksi) |
| Yield strength (0.2% Proof Strength) | ≥450 MPa (65 ksi) |
| Stretching | ≥25% |
| Hardness (Max) | 270 HB |
| Impact resistance (Charpy V-Notch, 20°C) | 100 J (74 ft.lb) |
| Property | Value |
|---|---|
| Density | 7.8 g/cm³ |
| Heat capacity (20°C) | 500 J/kg K |
| Coefficient of thermal expansion (20 – 100°C) | 13.0 x 10⁻⁶ K⁻¹ |
| Thermal conductivity (20°C) | 15 W/m K |
| Electrical resistivity (20°C) | 0.80 Ω mm²/m |
| Modulus of elasticity (20°C) | 200 GPa |
F51 DUPLEX stainless steel S31803 is available in the following shapes:
Thanks to its high mechanical strength and corrosion resistance, DUPLEX F51 S31803 is widely used in the following sectors: