2507 Super Duplex
Data verified2507 is a super duplex stainless with 25% chromium, 4% molybdenum and high nitrogen, giving a PREN above 40 and outstanding resistance to pitting, crevice corrosion and chloride stress corrosion in seawater and offshore service.
Chemical composition
| Element | Content (%) |
|---|---|
| C | ≤0.030 |
| Si | ≤0.80 |
| Mn | ≤1.20 |
| P | ≤0.035 |
| S | ≤0.020 |
| Cr | 24.00–26.00 |
| Ni | 6.00–8.00 |
| Mo | 3.00–5.00 |
| Cu | ≤0.50 |
| N | 0.24–0.32 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Delivery condition | Solution annealed |
| Hardness | ≤310 HB |
| Tensile strength | 795–1000 MPa |
| Yield strength | ≥550 MPa |
| Density | 7.80 g/cm³ |
| Magnetic | Yes |
| PREN | ≥40 |
Heat treatment
Solution anneal 1025–1125 °C, water quench. Strict control of welding heat input and interpass temperature (max ~150 °C) is essential to avoid intermetallic phases.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.4410 |
| aisi | UNS S32750 |
| gb | 022Cr25Ni7Mo4N |
Compare side by side: 2507 Super Duplex vs 2205 Duplex
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Seawater piping and pumps, offshore oil and gas, subsea components, desalination high-pressure piping, chemical tankers.
Processing: The most demanding duplex to weld: qualified procedures, phase-balance checks and corrosion testing are standard; machining requires rigid setups and sharp tooling.
FAQ
- 2507 or 904L for seawater?
- 2507 usually wins: higher strength, PREN above 40 and immunity to chloride stress corrosion, while 904L is fully austenitic and easier to form and weld for complex shapes.
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Ask for a quotationVisit NasteelSource: ASTM A240 / EN 10088 published ranges (UNS S32750) · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.