Super Duplex 2507 is a nitrogen-alloyed super duplex stainless steel with a PRE (Pitting Resistance Equivalent) exceeding 40, specifically engineered for service in aggressive chloride-containing environments. With 25% chromium, 7% nickel, 4% molybdenum, and 0.27% nitrogen, it offers exceptional resistance to localized corrosion, stress corrosion cracking, and erosion combined with mechanical strength approximately twice that of 316L. This grade is the preferred material for offshore platforms, chemical process equipment, and desalination plants requiring maximum corrosion resistance in seawater and sour service .
1. Product Specifications & Physical DataZYTC Alloy supplies Super Duplex 2507 in comprehensive mill forms for oil & gas, chemical processing, and marine applications requiring verified corrosion resistance and mechanical properties. Available Forms: Coil, plate, sheet, pipe, tube, bar, rod, forgings, and flanges . Specifications: UNS S32750, EN 10088-3 1.4410 (X2CrNiMoN25-7-4), ASTM A182 F53, NORSOK MDS D51-D58, NACE MR0175/ISO 15156 .
| Chemical Composition (Weight %) | Super Duplex 2507 Specification |
|---|
| 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 max. | | Manganese (Mn) | 1.20 max. | | Silicon (Si) | 0.80 max. | | Copper (Cu) | 0.50 max. | | Phosphorus (P) | 0.035 max. | | Sulfur (S) | 0.020 max. | | Iron (Fe) | Balance |
| Physical Properties | Metric | Imperial |
|---|
| Density | 7.8 g/cm³ | 0.281 lb/in³ | | Melting Point | 1350°C | 2460°F | | Modulus of Elasticity | 200 GPa | 29.0 × 10⁶ psi | | Thermal Conductivity | 17 W/m·K | 118 BTU·in/hr·ft²·°F | | Coefficient of Expansion (20-100°C) | 13.0 µm/m·°C | 7.2 µin/in·°F |
| Mechanical Properties (Minimum) | Metric | Imperial |
|---|
| Tensile Strength | 800 - 1000 MPa | 116 - 145 ksi | | Yield Strength (0.2% offset) | 550 MPa | 80 ksi | | Elongation | 25% | 25% | | Hardness (Brinell) | 290 max. | 290 max. | | Impact Strength (Charpy V, -46°C) | 35 J | 26 ft·lbf |
2. Operating Conditions & Selection CriteriaSuper Duplex 2507 is specified when designers require maximum corrosion resistance and strength for the most demanding chloride and sour service applications. Service Temperature Range: Optimized for applications from -50°C to 300°C (-58°F to 572°F); embrittlement risk above 300°C limits high-temperature service . Corrosion Resistance: PRE > 40 provides exceptional resistance to pitting and crevice corrosion in seawater and chloride environments . Stress Corrosion Cracking: Superior resistance to chloride SCC due to high alloy content and duplex microstructure . Mechanical Strength: Yield strength > 550 MPa enables significant weight reduction compared to austenitic grades . Sour Service: NACE MR0175/ISO 15156 approved for oil & gas equipment in H₂S environments up to high chloride concentrations . Erosion Resistance: Excellent resistance to erosion-corrosion in high-velocity seawater systems .
3. Fabrication & Material ComparisonHeat Treatment: Solution anneal 1025-1125°C (1877-2057°F), water quench; rapid cooling essential to maintain phase balance and prevent sigma phase formation . Welding: Good weldability with controlled heat input (0.5-1.5 kJ/mm); matching super duplex filler metals (2507/P100) required to maintain corrosion resistance . Forming: Higher strength requires more powerful equipment than austenitic or standard duplex grades . Machining: Higher cutting forces than 2205; requires rigid setups, sharp tools, and adequate coolant; work-hardening rate significant . Material Comparison: vs. Duplex 2205: Higher alloy content provides superior pitting resistance (PRE 40+ vs. 35); higher strength; specified for more aggressive environments . vs. 316L: 4× higher pitting resistance; twice the yield strength; superior SCC resistance . vs. 904L: Better localized corrosion resistance; higher strength; more cost-effective for seawater service . vs. 254 SMO: Comparable pitting resistance with higher strength; duplex microstructure offers better SCC resistance .
4. ApplicationsOil & Gas: Offshore platforms, subsea equipment, process piping, heat exchangers, fire-fighting systems, injection and ballast water systems Chemical Processing: Heat exchangers, vessels, columns, piping for aggressive chloride-containing media Desalination: High-pressure RO plants, seawater piping, evaporators Marine: Seawater cooling systems, propeller shafts, pump components Power Generation: FGD systems, scrubbers, absorber towers, ducting Pulp & Paper: Bleaching equipment, digesters Structural Components: High-strength, corrosion-resistant parts, bridges, offshore structures
Contact ZYTC Alloy for certified Super Duplex 2507 materials with complete traceability, ASTM/EN/NORSOK specifications, technical datasheets, and competitive pricing on standard sizes or custom-fabricated components. Email: daisy@zytcsteel.com WhatsApp/WeChat: +86 17335753350 |
