2507
1.4410 · EN 10088 · 1.4410
2507 is a stainless steel (Super Duplex family) to EN 10088 (1.4410). It has a specified 0.2 % proof stress of 550 MPa and a typical tensile strength of about 750 MPa, with a uniform elongation of 25 %. Nominal carbon content is around 0.03 %. For nonlinear FEA, a bilinear model uses E = 200 GPa up to yield and a tangent modulus of 815 MPa above it. The mixed ferrite/austenite (duplex) structure combines high strength with strong resistance to chloride pitting and stress-corrosion cracking.
Bilinear material model — nonlinear FEA
Uniform elongation εu = 25.0% · conservative analysis limit ½εu = 12.5%
Bilinear (BISO) approximation. Elastic modulus E up to the 0.2% proof stress R_p0.2, then a single tangent slope Eₜ to the ultimate tensile strength: Eₜ = (Rₘ − R_p0.2) / (εu − R_p0.2/E − 0.002), where εu is the uniform elongation and Rₘ is a typical (nominal) UTS within the specified band. The half-εu figure is a conservative strain limit for the analysis. Treat these as guidance for first-pass models; for critical work use a measured true stress–strain curve for the actual product and condition.
Ratings — engineering judgement
Weldabilitygood
Weldable with controlled heat input to preserve the ferrite/austenite balance; use a duplex filler.
Machinabilitymoderate
Soft and gummy at low carbon — sharp tooling helps surface finish.
Corrosion resistanceexcellent
Very high resistance including chloride pitting and stress-corrosion — suited to aggressive/marine service.
Hardenabilitylow
Limited hardenability at low carbon — surface hardening is possible but through-hardening is not.
Toughnessmoderate
Adequate toughness for general use at ambient temperature.
Indicative ratings derived from composition and family — engineering guidance, not specification values.
Physical properties
| Density | 7800 | kg/m³ |
| Elastic modulus | 200 | GPa |
| Shear modulus | 76.9 | GPa |
| Poisson's ratio | 0.30 | |
| Thermal expansion | 13.0 | ×10⁻⁶/°C |
| Thermal conductivity | 16 | W/(m·K) |
| Specific heat | 500 | J/(kg·K) |
| Magnetic | Yes |
Typical values for super duplex steel — use the mill certificate for the specific product.
Chemical composition (wt %)
Composition per EN 10088 / AISI for 2507 (1.4410).
Available forms
Common applications
- Process, food and pharmaceutical equipment
- Architectural and marine hardware
- Fasteners and fittings for corrosive service
- Tanks, pipework and heat exchangers
History
Duplex stainless steels carry roughly equal ferrite and austenite, combining the high strength and chloride-SCC resistance of ferritics with the toughness of austenitics. Controlled nitrogen alloying in the 1970s–80s made them weldable and reliable, and they now dominate demanding chloride and offshore service. A super duplex (~25 % Cr, high Mo/N) for the most severe chloride and offshore service.
- 1930First duplex grades produced (Avesta, Sweden)
- 1980Nitrogen-alloyed weldable duplex (2205) commercialised
- 1990Super- and lean-duplex grades extend the range
This profile is generated from the grade's core data and family. Composition is decoded from the designation where its naming system defines it; physical properties are family-typical and ratings are indicative. Confirm critical values against the governing standard or the mill certificate. Equivalents, historical designations and hand-written expert notes are added per grade over time.