The characteristic feature of duplex stainless steels is their dual phase microstructure, comprising of approximately 50% of austenitic and 50% of ferritic. This provides the material with an excellent combination of high strength and corrosion resistance.
Pitting Corrosion – The resistance to pitting corrosion may be compared to other grades by using the pitting index PREN. The higher the PREN value, the better the pitting resistance.
| C | Si | Mn | P | S | Cr | Ni | Mo | N | PREN | Fe | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Min | - | - | - | - | - | 21.00 | 4.50 | 2.50 | 0.08 | 33.00 | - |
| Max | 0.03 | 1.00 | 2.00 | 0.030 | 0.020 | 23.00 | 6.50 | 3.50 | 0.20 | - | - |
| Property | Value |
|---|---|
| U.T.S | 90 KSI Min (620 N/mm2) |
| 0.2% Proof Stress | 65 KSI Min (450 N/mm2) |
| Elongation | 25% |
| Red of Area | 45% |
| CVN Impacts @ -40°C (-40°F) | 40 Joules (30 ft-lbf) |