Super Duplex 2507 Stainless Steel Plate Sheet UNS S32750 High Strength Corrosion Resistant
Super Duplex 2507 (UNS S32750) sheets represent the highest level of duplex stainless steel technology, offering an exceptional combination of mechanical strength and corrosion resistance. This advanced material is specifically engineered for service in the most demanding environments, including high-chloride seawater, acid chloride media, and sour gas applications.
The designation "Super Duplex" refers to the premium grade of duplex stainless steel with a Pitting Resistance Equivalent Number (PREN) exceeding 40. UNS S32750 achieves this through a carefully balanced chemistry featuring high levels of chromium (24-26%), molybdenum (3-5%), and nitrogen (0.24-0.32%). The result is a material that significantly outperforms standard duplex grades like 2205 and conventional austenitic grades such as 316L.
| Parameter | Details |
|---|---|
| Product Name | Super Duplex 2507 Sheets |
| UNS Number | S32750 |
| EN Equivalent | 1.4410 |
| Trade Name | SAF 2507 (equivalent) |
| Standard | ASTM A240 / ASME SA-240 |
| Form | Sheet, Plate, Coil |
| Manufacturing Process | Hot rolled or cold rolled, solution annealed + water quenched |
| Thickness Range | 0.5mm – 6.0mm (sheet) / 6.0mm – 50mm (plate) |
| Width Range | 500mm – 2000mm |
| Length Range | 1000mm – 6000mm |
| Surface Finish | 2B (bright cold rolled), 2D (dull), No.1 (annealed & pickled), BA (bright annealed) |
| Packing Method | Waterproof paper interleaved between layers, wooden pallets, rust-preventive oil (optional), edge protectors, steel strapping |
| Edge Condition | Mill edge or slit edge |
| Certification | Mill Test Certificate EN 10204 Type 3.1 (or Type 3.2 upon request) |
| Third-Party Inspection | SGS, Bureau Veritas, and Intertek are available |
The chemical composition of Super Duplex 2507 is strictly controlled to achieve the required phase balance and corrosion resistance. Below are the requirements per ASTM A240:
| Element | Content (% by weight) |
|---|---|
| Carbon (C) | 0.030 max |
| Manganese (Mn) | 1.20 max |
| Silicon (Si) | 0.80 max |
| Phosphorus (P) | 0.035 max |
| Sulfur (S) | 0.020 max |
| Chromium (Cr) | 24.00 – 26.00 |
| Nickel (Ni) | 6.00 – 8.00 |
| Molybdenum (Mo) | 3.00 – 5.00 |
| Nitrogen (N) | 0.24 – 0.32 |
| Copper (Cu) | 0.50 max |
PRE (Pitting Resistance Equivalent) Calculation: PRE = Cr% + 3.3(Mo% + 0.5W%) + 16N%
For UNS S32750, the PRE value typically exceeds 40, indicating excellent resistance to pitting and crevice corrosion in chloride environments.
After proper solution annealing and water quenching, Super Duplex 2507 sheets deliver the following mechanical properties:
| Property | Required Value (Typical) |
|---|---|
| Tensile Strength | 800 MPa (116 ksi) min |
| Yield Strength (0.2% offset) | 550 MPa (80 ksi) min |
| Elongation (2" or 50mm) | 25% min |
| Hardness (Brinell) | 310 HBW max |
| Hardness (Rockwell C) | 32 HRC max |
| Charpy V-Notch Impact (Longitudinal) | 100 J min at -20°C |
| Charpy V-Notch Impact (Transverse) | 45 J min at -20°C |
| Modulus of Elasticity | 200 GPa (29,000 ksi) |
| Density | 7.8 g/cm³ (0.28 lb/in³) |
Comparison of strength levels:
| Material | Yield Strength (min) | Relative Strength |
|---|---|---|
| 304 Stainless Steel | 205 MPa | 1.0x |
| 316L Stainless Steel | 205 MPa | 1.0x |
| 2205 Duplex | 450 MPa | 2.2x |
| Super Duplex 2507 | 550 MPa | 2.7x |
Super Duplex 2507 sheets are specified for demanding applications across multiple industries where high strength and exceptional corrosion resistance are required.
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Seawater cooling systems and firewater lines
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Offshore platform topside equipment
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Desalination plant evaporators and piping
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Ballast water treatment systems
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Hydraulic and instrumentation systems
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Subsea manifolds and jumpers
The high PREN value (>40) ensures reliable performance in seawater, even in crevice conditions, stagnant flow, or high-velocity applications.
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Heat exchangers handling chloride-containing cooling water
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Chemical tankers and storage vessels
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Evaporators, crystallizers, and reactors
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Flue Gas Desulfurization (FGD) components
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Process piping for organic and inorganic acids
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Bleaching equipment in pulp and paper mills
UNS S32750 resists pitting, crevice corrosion, and stress corrosion cracking, where 316L and even 2205 duplex would experience premature failure.
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Process equipment on offshore platforms and FPSOs
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Sour service components (NACE MR0175 / ISO 15156 compliant)
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High-pressure flowlines and manifolds
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Separation and treatment vessels
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Subsea Christmas trees and wellhead equipment
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Seawater-cooled condensers and heat exchangers
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Cooling water intake systems
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FGD absorber towers and ductwork
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Geothermal power plant equipment
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Bleaching plant digesters and towers
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Chlorine dioxide bleaching systems
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White liquor and green liquor tanks
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Washers and filters
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High-performance building facades in coastal locations
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Bridge components exposed to de-icing salts
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Marine architectural features and fittings
When placing an order for Super Duplex 2507 (UNS S32750) sheets, please specify the following to ensure accurate quotation and delivery:
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Quantity – Number of sheets or total weight (metric tons)
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Dimensions – Thickness × Width × Length (mm or inches)
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Surface Finish – 2B, 2D, No.1, BA, or custom
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Edge Condition – Mill edge or slit edge
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Certification Requirements – EN 10204 Type 3.1 or Type 3.2
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Third-Party Inspection – SGS, BV, Intertek, or as specified
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Supplementary Requirements – Ferrite measurement, ultrasonic testing, intergranular corrosion test, etc.
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Packing Preference – Standard export packing or custom requirement
For inquiries, technical data sheets, material selection assistance, or a quotation for Super Duplex 2507 (UNS S32750) corrosion-resistant high-strength sheets, please contact our sales team.
We provide:
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Mill test certificates with full traceability to heat numbers
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Competitive pricing for project quantities and regular stocking orders
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Reliable delivery to global destinations
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Technical support from material selection through fabrication
All inquiries are responded to within 24 hours.
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