Product Description
2507 (UNS S32750/EN 1.4410) is a premium super duplex stainless steel designed to deliver exceptional corrosion resistance and high mechanical strength in the most demanding environments. With a carefully balanced austenitic-ferritic microstructure, this advanced alloy contains high levels of chromium (24-26%), nickel (6-8%), molybdenum (3-5%), and nitrogen (0.24-0.32%), creating a material with superior resistance to chloride pitting, crevice corrosion, and stress corrosion cracking.
The dual-phase structure of 2507 super duplex stainless steel combines the best properties of both austenitic and ferritic steels, resulting in mechanical properties that are 50-100% higher than most conventional austenitic stainless steels. 2507’s high pitting resistance equivalent (PRE) value of approximately 42 provides corrosion resistance comparable to 6-moly austenitic grades, making it an ideal solution for aggressive chloride-containing environments.
FUSHUN METAL supplies premium quality 2507 super duplex stainless steel that offers excellent performance in harsh conditions where standard duplex grades like 2205 would be insufficient. This versatile material is particularly valuable in marine environments, chemical processing, oil and gas production, and other applications requiring a combination of high strength and outstanding corrosion resistance at service temperatures up to 600°F (315°C).
Applications
2507 super duplex stainless steel is engineered for the most challenging environments where its unique combination of superior corrosion resistance and high mechanical strength provides exceptional performance and reliability. Key applications include:
- Oil and Gas Industry: Offshore platforms, process equipment, firewater systems, blast and firewalls, strake clamps, downhole tubing, control and wire lines, band clamps, pumps, valves, chokes, Christmas trees, pipework, flanges, bolting, connectors, and manifolds. 2507’s resistance to sour gas environments makes it particularly valuable in oil and gas production.
- Chemical Processing: Pressure vessels, storage tanks, piping systems, heat exchangers, and reactors handling aggressive chemicals. The exceptional resistance to chloride pitting and crevice corrosion makes 2507 ideal for processing equipment exposed to halide-containing media.
- Desalination and Water Treatment: Seawater handling systems, high-pressure pumps, piping, and heat exchangers in desalination facilities and water reuse plants where the combination of corrosion resistance and high strength provides long-term reliability.
- Pulp and Paper Industry: Digesters, bleach washers, and other equipment exposed to corrosive chloride-containing chemicals in pulp processing operations.
- Marine Applications: Propeller shafts, fasteners, structural components, and seawater cooling systems where resistance to seawater corrosion is critical.
- Food, Beverage, and Pharmaceutical: Process equipment where high corrosion resistance, strength, and product purity are essential requirements.
- Architecture and Infrastructure: Structural applications in aggressive environments, including bridges, dam weirs, and coastal structures where long service life is required despite exposure to chloride-containing environments.
The combination of high strength and excellent corrosion resistance makes 2507 super duplex stainless steel an economical alternative to more expensive nickel-based alloys in many applications, offering an optimal balance of performance and cost-effectiveness in demanding service conditions.
Standards
2507 super duplex stainless steel conforms to numerous international standards and specifications, ensuring consistent quality and performance in demanding applications:
American Standards:
- UNS: S32750
- ASTM A240: Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
- ASTM A276/A276M: Standard Specification for Stainless Steel Bars and Shapes
- ASTM A479/A479M: Standard Specification for Stainless Steel Bars and Shapes for Use in Boilers and Other Pressure Vessels
- ASTM A182: Standard Specification for Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Forged Fittings, and Valves and Parts for High-Temperature Service (Grade F53)
- ASME: SA-240, SA-276, SA-479, SA-182 (Grade F53); P-number 10H, Group Number 1
European Standards:
- EN Number: 1.4410
- EN 10088-3: Stainless steels – Technical delivery conditions for semi-finished products, bars, rods and sections for general use
- EN 10272: Stainless steel bars for pressure purposes
- EN 10028-7:2007: Flat products made of steels for pressure purposes – Stainless steels
International Standards:
- NACE MR0175/ISO 15156: Materials for use in H₂S-containing environments in oil and gas production
- NORSOK M-650: Qualification of manufacturers of special materials
- NORSOK M-630: Material data sheets and element data sheets for piping (MDS-D57)
These comprehensive standards ensure that 2507 super duplex stainless steel from FUSHUN METAL meets the rigorous requirements for use in critical applications across various industries, particularly where high strength and exceptional corrosion resistance are essential.
Material Designation and Chemical Composition
2507 super duplex stainless steel is known by various designations in different standards and specification systems:
| Standard System | Designation |
|---|---|
| UNS | S32750 |
| EN | 1.4410 |
| EN Name | X2CrNiMoN25-7-4 |
| ASTM | F53 |
| Common Name | 2507 |
The chemical composition of 2507 super duplex stainless steel is carefully controlled to ensure optimal performance in demanding environments:
| Element | Minimum (%) | Maximum (%) |
|---|---|---|
| Chromium (Cr) | 24.0 | 26.0 |
| Nickel (Ni) | 6.0 | 8.0 |
| Molybdenum (Mo) | 3.0 | 5.0 |
| Nitrogen (N) | 0.24 | 0.32 |
| Carbon (C) | – | 0.030 |
| Silicon (Si) | – | 0.80 |
| Manganese (Mn) | – | 1.20 |
| Phosphorus (P) | – | 0.035 |
| Sulfur (S) | – | 0.020 |
| Copper (Cu) | – | 0.50 |
| Iron (Fe) | Balance | – |
The high levels of chromium, molybdenum, and nitrogen in 2507 result in a Pitting Resistance Equivalent Number (PREN = %Cr + 3.3 × %Mo + 16 × %N) of approximately 42, providing exceptional resistance to localized corrosion in aggressive environments. The balanced chemical composition also ensures an optimal dual-phase microstructure with approximately equal proportions of austenite and ferrite for superior mechanical properties and corrosion resistance.
Physical and Mechanical Properties
2507 super duplex stainless steel offers an exceptional combination of high strength and excellent corrosion resistance, making it ideal for demanding applications where conventional stainless steels would be inadequate.
Mechanical Properties
The mechanical properties of 2507 are significantly superior to those of conventional austenitic stainless steels:
| Property | Value |
|---|---|
| Ultimate Tensile Strength (minimum) | 116 ksi (800 MPa) |
| 0.2% Yield Strength (minimum) | 80 ksi (550 MPa) |
| Elongation (minimum) | 15% |
| Hardness (maximum) | 32 HRC (290 HBW) |
According to EN 10088-3 for 1.4410 (solution annealed condition, maximum diameter 160mm):
| Property | Value |
|---|---|
| Ultimate Tensile Strength | 730-930 MPa (106-135 ksi) |
| 0.2% Proof Strength (minimum) | 530 MPa (77 ksi) |
| Elongation (minimum) | 25% |
| Impact Energy at 20°C (minimum) | 100 J |
| Impact Energy at -40°C (minimum) | 40 J |
Physical Properties
| Property | Value |
|---|---|
| Density | 0.282 lb/in³ (7.8 g/cm³) at 68°F (20°C) |
| Melting Range | 2570-2660°F (1410-1460°C) |
| Modulus of Elasticity at 68°F (20°C) | 29 × 10⁶ psi (200 GPa) |
| Thermal Conductivity at 68°F (20°C) | 8.6 BTU·ft/ft²·hr·°F (15 W/m·K) |
| Coefficient of Thermal Expansion (68-212°F/20-100°C) | 7.2 × 10⁻⁶ in/in·°F (13.0 × 10⁻⁶ /K) |
| Specific Heat at 68°F (20°C) | 0.11 BTU/lb·°F (500 J/kg·K) |
| Electrical Resistivity | 0.80 × 10⁻⁶ Ω·m |
| Poisson’s Ratio | 0.3 |
Corrosion Resistance
2507 super duplex stainless steel offers exceptional resistance to various forms of corrosion:
- Pitting and Crevice Corrosion: With a PREN value of approximately 42, 2507 provides excellent resistance to localized corrosion in chloride-containing environments. Its critical pitting temperature (CPT) of approximately 185°F (85°C) is significantly higher than that of 2205 (120°F/49°C) and 316L (64°F/18°C).
- Stress Corrosion Cracking: Superior resistance to chloride stress corrosion cracking compared to conventional austenitic stainless steels.
- General Corrosion: Excellent resistance to uniform corrosion in a wide range of aggressive media, including sulfuric acid and hydrochloric acid at moderate concentrations and temperatures.
- Erosion Corrosion: High hardness and corrosion resistance provide good protection against erosion-corrosion in flowing media.
The corrosion resistance of 2507 is particularly valuable in seawater and other chloride-containing environments, making it an ideal choice for offshore and marine applications.
Heat Treatment
2507 super duplex stainless steel is supplied in the solution annealed condition to ensure optimal corrosion resistance and mechanical properties. The recommended heat treatment process involves:
- Solution Annealing Temperature: 1040-1120°C (1904-2048°F)
- Holding Time: Approximately 30 minutes at solution annealing temperature
- Cooling: Rapid cooling in water
Like other duplex stainless steels, 2507 is susceptible to secondary phase formation at elevated temperatures between 350-950°C (662-1742°F), which can reduce both toughness and corrosion resistance. For this reason, 2507 should be limited to applications below 600°F (315°C). Stress relief treatments, when necessary, can be performed at 500-550°C (932-1022°F) for a maximum of 5 hours.
Available Dimensions
FUSHUN METAL offers 2507 super duplex stainless steel in a comprehensive range of product forms and dimensions to meet diverse application requirements:
Plate and Sheet
| Product Form | Thickness | Width | Length |
|---|---|---|---|
| Plate | 4.0 mm – 150 mm (0.157″ – 5.9″) | Up to 3,000 mm (118″) | Up to 12,000 mm (472″) |
| Sheet | 0.5 mm – 4.0 mm (0.020″ – 0.157″) | Up to 1,500 mm (59″) | Up to 6,000 mm (236″) |
Bar and Rod
| Product Form | Diameter/Dimension | Length |
|---|---|---|
| Round Bar | 5 mm – 300 mm (0.197″ – 11.8″) | Up to 6,000 mm (236″) |
| Square Bar | 10 mm – 200 mm (0.394″ – 7.87″) | Up to 6,000 mm (236″) |
| Flat Bar | Thickness: 5 mm – 100 mm (0.197″ – 3.94″) Width: 10 mm – 300 mm (0.394″ – 11.8″) |
Up to 6,000 mm (236″) |
| Hexagonal Bar | 10 mm – 100 mm (0.394″ – 3.94″) across flats | Up to 6,000 mm (236″) |
Pipe and Tube
| Product Form | Outside Diameter | Wall Thickness | Length |
|---|---|---|---|
| Seamless Pipe | 6 mm – 508 mm (0.236″ – 20″) | Schedule 10S – XXS | Up to 12,000 mm (472″) |
| Welded Pipe | 6 mm – 1,219 mm (0.236″ – 48″) | Schedule 10S – XXS | Up to 12,000 mm (472″) |
| Seamless Tube | 6 mm – 50.8 mm (0.236″ – 2″) | 0.5 mm – 12.7 mm (0.020″ – 0.500″) | Up to 25,000 mm (984″) |
Wire
| Diameter | Condition | Form |
|---|---|---|
| 0.1 mm – 12 mm (0.004″ – 0.472″) | Annealed, Hard, Spring Temper | Coils, Spools, Cut Lengths |
Fittings and Flanges
We also offer a complete range of fittings and flanges in 2507 super duplex stainless steel, manufactured to international standards including ASME/ANSI B16.5, B16.9, B16.11, and B16.47.
Custom dimensions and special profiles can be produced to meet specific customer requirements. Please contact our sales team for more information about non-standard sizes and special specifications.
Fabrication Information
2507 super duplex stainless steel can be successfully fabricated using conventional methods, but there are some important considerations to ensure optimal performance of the finished components:
Forming
Due to its high strength, forming of 2507 requires more force than austenitic stainless steels:
- Hot Forming: Should be performed in the temperature range of 1200-1000°C (2192-1832°F). Note that the strength of duplex material is lower at high temperatures.
- Cold Forming: Greater working forces are needed compared to austenitic steels. The spring back is relatively high because of the high yield point.
- Post-forming Heat Treatment: Solution annealing is normally recommended after more than 10% cold deformation or after hot forming.
Welding
2507 has good weldability but requires specific procedures to maintain optimal properties:
- Recommended Filler Metal: E2594 or ER2594 (ISO 25 9 4 NL) to ensure weld properties comparable to the parent metal.
- Heat Input: Control heat input to avoid excessive ferrite formation and precipitation of intermetallic phases.
- Interpass Temperature: Should be kept below 150°C (302°F) to avoid precipitation of detrimental phases.
- Preheating: Not required and should be avoided.
- Post-weld Heat Treatment: Generally not required for corrosion resistance if proper welding procedures are followed.
Machining
2507 is more difficult to machine than conventional austenitic steels due to its high strength and work hardening rate:
- Lower cutting speeds are recommended compared to austenitic stainless steels.
- Rigid tooling setups and adequate cooling are essential.
- High-speed tools may perform relatively better on duplex grades compared to their performance on austenitic grades.
Surface Finishing
Surface finish options for 2507 include:
- Pickled and passivated
- Mechanically polished
- Electropolished
- Machined and peeled
Proper surface treatment is important to maintain optimal corrosion resistance, particularly after welding or other thermal processes that may affect the surface condition.
Why Choose FUSHUN METAL for 2507 Super Duplex Stainless Steel
When selecting a supplier for premium 2507 super duplex stainless steel, FUSHUN METAL stands as your preferred partner for several compelling reasons:
Superior Quality Assurance
At FUSHUN METAL, we implement rigorous quality control processes throughout our production chain. Our 2507 super duplex stainless steel undergoes comprehensive testing including chemical analysis, mechanical testing, metallographic examination, and corrosion testing to ensure full compliance with international standards and specifications. This meticulous attention to quality guarantees that our products consistently deliver the exceptional performance required in the most demanding applications.
Metallurgical Expertise
Our team of metallurgical specialists possesses extensive experience and knowledge in the production and processing of super duplex stainless steels. This expertise enables us to provide valuable technical support to help you select the optimal material specifications for your specific application requirements. We can assist with material selection, fabrication recommendations, corrosion resistance evaluations, and problem-solving to ensure the success of your projects.
Comprehensive Product Range
FUSHUN METAL offers one of the most extensive ranges of 2507 super duplex stainless steel products available, including plate, sheet, bar, pipe, tube, fittings, flanges, and custom components. This diverse product portfolio allows you to source all your super duplex stainless steel requirements from a single, reliable supplier, streamlining your procurement process and ensuring consistency across your projects.
Global Supply Capabilities
With our robust global supply network, FUSHUN METAL can deliver 2507 super duplex stainless steel products to customers worldwide with competitive lead times. Our logistics expertise ensures your materials arrive when and where you need them, supporting your project schedules and operational requirements.
Value-Added Services
Beyond supplying premium materials, we offer a range of value-added services including custom cutting, machining, heat treatment, surface finishing, and non-standard dimensions to meet your specific requirements. Our ability to provide tailored solutions helps you optimize your manufacturing processes and reduce overall costs.
For your next project requiring the exceptional corrosion resistance and high strength of 2507 super duplex stainless steel, we invite you to contact our technical team to discuss your specific requirements. Our experts are ready to help you select the optimal material specifications and provide the premium quality products you need for reliable, long-term performance in even the most challenging environments.
