Duplex 2304 stainless steel is a 23% chromium, 4% nickel, molybdenum-free duplex stainless steel whose structure is a balance of ferritic and austenitic. It has general corrosion resistance similar or better than Alloys 304L and 316L but with yield strength nearly double that of austenitic stainless steels. Its duplex microstructure and low nickel and high chromium contents also allows Duplex 2304 to demonstrate improved stress corrosion resistant properties compared to 304 and 316. It is designed to feature high mechanical strength, good weldability, good corrosion resistance, high resistance to stress corrosion cracking, good machinability, low thermal expansion, good fatigue properties, high thermal conductivity, and easy fabrication.
Typical Values (Weight %)
| Carbon | Chromium | Nickel | Molybdenum | Nitrogen | Others |
| 0.020 | 23 | 4 | 0.2 | 0.1 | S=0.001 |
| PREN = [Cr%] = 3.3 [Mo%] = 16 [N%] ≥ 24 |
Tensile Properties (Minimum Values)
| °C | Rp 0.2 MPa | Rp 1.0 MPa | Rp 1.0 MPa | °F | YS 0.2% Offset KSI | YS 0.1% Offset KSI | UTS KSI | Elongation % |
| 20 | 400 | 440 | 600 | 68 | 58 | 64 | 87 | 25 |
| 100 | 330 | 365 | 570 | 212 | 48 | 53 | 83 | 25 |
| 200 | 280 | 310 | 530 | 392 | 41 | 45 | 77 | 20 |
| 300 | 230 | 260 | 490 | 572 | 33 | 38 | 71 | 20 |
Values obtained for hot rolled plates (th ≤ 2"). Alloy 2304 must not be used for a long time at temperatures higher than 300°C (572°F), where precipitation hardening phenomenon occurs.
Toughness Values (KCV Minimum Values)
| Temp. | -50°C | +20°C | -60°F | +70°F |
| Single | 75 J/cm_ | 90 J/cm_ | 54 ft. lbs | 65 ft. lbs |
| Average (5) | 90 J/cm_ | 150 J/cm | 65 ft. lbs | 87 ft. lbs |
Hardness (Typical Values)
| Average (5) | HV10 180-230 | HB : 180-230 | HRC _ 20 |
Density : 7,800 kg/m3 - 0.28 lb/in3
| Interval Temper °C | Thermal expansion ax10M-bK-1 | °C | Resistivity (μ_ cm) | Thermal conductivity (W.m-1.K-1) | Specific heat (J.kg-1.K-1 | Young modulus E (GPa) | Shear modulus G (GPa) |
| 20-100 | 13 | 20 | 80 | 17 | 450 | 200 | 75 |
| 20-100 | 13 | 100 | 92 | 18 | 500 | 190 | 73 |
| 20-200 | 13.5 | 200 | 100 | 19 | 530 | 180 | 70 |
| 20-300 | 14 | 300 | 105 | 20 | 560 | 170 | 67 |
Qinghe Steel is a full line supplier and processer of stainless steel coil, sheet, plate, bar, and strip products. We stock many grades of stainless steel, including 300 and 400 series stainless, annealed and in various tempers and high temperature grades, for shipments worldwide. View our steel center here
