Stainless Steel 2507
UNS S32750 · EN 1.4410, X2CrNiMoN25-7-4 · JIS Super Duplex 2507 · GB 022Cr25Ni7Mo4N · also Alloy 2507
2507 (UNS S32750, 1.4410, X2CrNiMoN25-7-4, Alloy 2507) is the benchmark super duplex stainless, 25Cr-7Ni-4Mo-N, with PREN above 40 and a balanced ferrite/austenite structure.
Values for the Solution Annealed condition
2507 tempers and conditions
2507 is supplied in 6 conditions, soft to hard. Solution Annealed is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
hot rolled/forged bar and sections, annealed and pickled | Pick for large-section bar, forged shafts and flanges where cold drawing is impractical. | 600 | 860 | 28 | 28 HRC | 2.2 % IACS |
weld metal / HAZ, no post-weld solution anneal | Reference condition for fabricated joints using 25.10.4.L filler; expect somewhat lower toughness and corrosion margin than parent metal. | 600 | 850 | 22 | 28 HRC | 2.2 % IACS |
mill annealed (nominally equivalent to solution annealed for duplex) | Use when a supplier simply calls the condition 'annealed'; duplex grades have no sub-critical anneal, so properties equal solution annealed. | 610 | 870 | 30 | 27 HRC | 2.2 % IACS |
Solution AnnealedDefault 1040–1120 °C solution treated and water quenched | Standard supply condition for plate, sheet, pipe, forgings and hot-finished bar; best corrosion resistance and toughness. | 620 | 880 | 30 | 28 HRC | — |
cold drawn bar/wire, lightly work hardened | Choose for small-diameter bar with tight tolerance, better finish and higher yield strength for fasteners and shafts. | 780 | 950 | 20 | 32 HRC | 2.2 % IACS |
cold rolled/cold pilgered tube and strip, high strength condition | For thin-wall tubing, springs and umbilicals where strength matters more than ductility; corrosion resistance essentially unchanged, but residual stress raises SCC sensitivity. | 850 | 1,000 | 18 | 34 HRC | 2.2 % IACS |
What is 2507?
2507 (UNS S32750, 1.4410, X2CrNiMoN25-7-4, Alloy 2507) is the benchmark super duplex stainless, 25Cr-7Ni-4Mo-N, with PREN above 40 and a balanced ferrite/austenite structure. Solution annealed it provides 620 MPa yield, 880 MPa tensile, 30 % elongation and 270 HB, with high chloride pitting and stress-corrosion resistance (score 88) in pipe, plate, bar and forgings for offshore and chemical service. Machinability is 22 and formability 45, service is limited to 300 °C, and cost sits well above 2205 — use 2205 or 2304 where PREN above 40 is not required. 2507 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,350°C (2,462 °F). 2507 has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 88% of stainless steel grades. Elongation at break is 30% and the elastic modulus is 200 GPa (29 Msi).
What is 2507 used for?
- Subsea pipework and manifolds
- Pump and valve bodies
- Seawater heat exchanger tubing
- Desalination plant equipment
- Chemical process pressure vessels
- Umbilical and hydraulic tubing
- Offshore riser and topside components
- Flue-gas desulfurisation hardware
Advantages
- Good corrosion resistance — 88/100, better than 97% of stainless steel grades
- High strength — 620 MPa (89.9 ksi), better than 88% of stainless steel grades
Limitations
- Difficult to machine — 22/100, worse than 95% of stainless steel grades
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
- High embodied carbon — 5.5 kg CO₂/kg, worse than 77% of stainless steel grades
2507 properties
Typical room-temperature values for 2507-Solution Annealed; bars are the position among stainless steel grades.
Physical3
2507 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,350°C (2,462 °F).
Mechanical16
2507 has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 88% of stainless steel grades. Elongation at break is 30% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
2507 is rated for continuous service to 300°C (572 °F). It conducts heat at 15 W/m·K (8.67 BTU/hr·ft·°F), worse than 59% of stainless steel grades. Thermal expansion is 13 µm/m·K (7.22 µin/in·°F).
Electrical3
2507 conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is excellent (88/100), better than 97% of stainless steel grades.
Sustainability4
Producing a kilogram of 2507 takes about 72 MJ of energy and emits 5.5 kg of CO₂ — more than 83% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
2507's machinability is poor (22/100, worse than 95% of stainless steel grades); weldability good (60/100); formability fair (45/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. 2507 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 2507
Is 2507 easy to machine?
Cuts like a very tough, work-hardening stainless: rigid setup, sharp positive-rake carbide, 25–40 % lower speed than 316L, heavy positive feed and copious coolant to avoid work-hardened skin and built-up edge.
Can 2507 be welded?
Weldable by GTAW/GMAW/SMAW/SAW with 25.10.4.L (2509) filler; no preheat, interpass below ~150 °C, controlled heat input and Ar+2 % N₂ backing to hold ~35–55 % ferrite and avoid σ/nitride precipitation.
Can 2507 be formed, bent or molded?
Cold form with about twice the force of 304 and generous springback allowance; hot form 950–1150 °C followed by full solution anneal and water quench — never finish in the 600–950 °C range.
Manufacturability
The process limits FabDigit applies to 2507. Every 2507 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Fair22 / 100 |
|---|---|
| ISO material group | M.2 |
| Cutting speed (rough / finish) | 90 / 110 m/min |
| Minimum wall | 1 mm |
| Minimum internal radius | 1.5 mm |
| Drill depth limit | 3.5× diameter |
| Best surface (machined / polished) | Ra 1.6 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Fair45 / 100 |
|---|---|
| Weldability | Better60 / 100 |
| Bendable | Yes |
2507 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| CASTM A240 max | ≤ 0.03 | 0.02 |
| Si | ≤ 0.8 | 0.4 |
| Mn | ≤ 1.2 | 0.8 |
| P | ≤ 0.04 | 0.02 |
| SEN 1.4410 limits S ≤0.015 | ≤ 0.02 | 0 |
| Cr | 24 – 26 | 25 |
| Ni | 6 – 8 | 7 |
| Mo | 3 – 5 | 4 |
| N | 0.24 – 0.32 | 0.28 |
| Cu | ≤ 0.5 | 0.2 |
| Febalance ≈62 % | balance |
What surface finishes work on 2507?
Pickle in HNO₃/HF and passivate after hot work or welding to restore the passive film; electropolishing or fine mechanical polishing gives best chloride performance — no anodizing.
Surface treatments FabDigit runs on stainless steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Plating
Organic Coating
CVD Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel 2507 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S32750
- EN / DIN / Werkstoff-Nr.
- 1.4410X2CrNiMoN25-7-4
- GB (China)
- 022Cr25Ni7Mo4N
- JIS
- Super Duplex 2507
- Trade names
- Alloy 2507
How much does 2507 cost?
2507 is a premium-cost stainless steel ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
2507 — frequently asked
What is 2507 used for?
2507 is typically used for subsea pipework and manifolds, pump and valve bodies, seawater heat exchanger tubing, desalination plant equipment, chemical process pressure vessels and umbilical and hydraulic tubing. In short: super-duplex marine stainless.
What is the yield strength of 2507?
2507 has a typical yield strength of 620 MPa (89.9 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 88% of stainless steel grades. Strength varies by condition: see the 6 listed tempers.
Is 2507 easy to machine?
Not especially — machinability is rated poor (22/100, worse than 95% of stainless steel grades). Cuts like a very tough, work-hardening stainless: rigid setup, sharp positive-rake carbide, 25–40 % lower speed than 316L, heavy positive feed and copious coolant to avoid work-hardened skin and built-up edge.
Can 2507 be welded?
Yes — weldability is rated good (60/100). Weldable by GTAW/GMAW/SMAW/SAW with 25.10.4.L (2509) filler; no preheat, interpass below ~150 °C, controlled heat input and Ar+2 % N₂ backing to hold ~35–55 % ferrite and avoid σ/nitride precipitation.
What surface finishes work on 2507?
Pickle in HNO₃/HF and passivate after hot work or welding to restore the passive film; electropolishing or fine mechanical polishing gives best chloride performance — no anodizing.
Can 2507 be formed, bent or molded?
Cold form with about twice the force of 304 and generous springback allowance; hot form 950–1150 °C followed by full solution anneal and water quench — never finish in the 600–950 °C range.
What is the maximum service temperature of 2507?
2507 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 2507 cost?
2507 is a premium-cost stainless steel ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in 2507?
Yes — 2507 is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet and Strip — ASTM International (2023)
- ASTM A479/A789/A790 — Bar and Seamless/Welded Duplex Tubing — ASTM International (2022)
- EN 10088-1/-2 — Stainless steels, grade 1.4410 (X2CrNiMoN25-7-4) — CEN (2014)
- Sandvik SAF 2507 / Sanmac 2507 datasheet — Alleima (Sandvik Materials Technology) (2022)
- Outokumpu 2507 (S32750) data sheet — Outokumpu (2021)
- Practical Guidelines for the Fabrication of Duplex Stainless Steels — IMOA (2014)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels — ASM International (1990)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.