Duplex stainless steels are magnetic and are far more corrosion resistant than more commonly used stainless grades, ie 302 and 316.
Super Duplex is also known as Alloy 32750 and SAF 2507.
| Element | Min % | Max % |
| C | – | 0.03 |
| Mn | – | 1.2 |
| Si | – | 0.80 |
| S | – | 0.015 |
| P | – | 0.035 |
| Cr | 24.0 | 26.0 |
| Ni | 6.0 | 8.0 |
| Mo | 3.0 | 4.5 |
| N | 0.24 | 0.35 |
| Cu | – | 0.5 |
| Fe | bal | |
Density
7.8 g/cm³ | 0.28 lb/in³
Melting Point
1350°C | 2460°F
Coefficient of Expansion
13.5 μm/m °C (25 – 100°C) | 7.5 x 10-6 in/in °F (70 – 200°F)
Modulus of Elasticity
200 kN/mm² | 29000 ksi
Modulus of Rigidity
77 kN/mm² | 11000 ksi
Heat Treatment of Finished Parts
| Condition as supplied by Alloy Wire | Type | Temperature | Time (Hr) | Cooling | |
| °C | °F | ||||
| Annealed or Spring Temper | Stress Relieve | 250 | 480 | 1 | Air |
Properties
| Condition | Approx. tensile strength | Approx. operating temperature | ||
| N/mm² | ksi | °C | °F | |
| Solution Annealed | < 1000 | < 145 | -200 to +300 | -330 to +570 |
| Spring Temper | 1300 – 1900 | 189 – 276 | -200 to +300 | -330 to +570 |