2207 Super Duplex Stainless Steel Pipe SCC Resistance For Extreme Environments
Duplex 2207 stainless steel plate is a super duplex grade characterized by a balanced austenitic-ferritic microstructure (approximately 50% austenite / 50% ferrite). This unique dual-phase structure delivers approximately twice the yield strength of standard austenitic grades like 304L or 316L, combined with exceptional resistance to chloride stress corrosion cracking (SCC), pitting, and crevice corrosion.
2207 is technically equivalent to UNS S32750 / EN 1.4410, commonly known as Super Duplex 2507. It represents the highest performance tier within the duplex stainless steel family, designed for the most demanding service environments including offshore platforms, seawater systems, chemical processing, and oil & gas exploration.
Key Features
| Feature | Description |
|---|---|
| Microstructure | Austenitic + Ferritic (≈50/50 dual-phase) |
| Yield Strength | ≥550 MPa (~2× stronger than 316L) |
| PREN | ≥42 (excellent pitting resistance) |
| Corrosion Resistance | Superior against SCC, pitting, crevice corrosion |
| Temperature Range | -50°F to 600°F (-46°C to 316°C) continuous service |
| Magnetic | Yes (due to ferrite phase) |
Equivalent Designations
| Standard | Grade |
|---|---|
| ASTM | UNS S32750 |
| EN | 1.4410 |
| AISI | 2207 |
| JIS | SUS329J4L |
| DIN | X2CrNiMoN25-7-4 |
Specifications & Size Range
| Parameter | Range |
|---|---|
| Thickness | 0.3 mm – 60 mm (custom up to 200 mm available) |
| Width | 50 mm – 3500 mm |
| Length | 1000 mm – 12000 mm (custom available) |
| Standard Coil Widths | 1000 mm, 1219 mm, 1240 mm, 1500 mm |
| Standard | ASTM A240 / A480, ASME SA240, EN 10088-2, JIS G4304/G4305 |
Surface Finishes
| Finish | Code | Characteristics | Application |
|---|---|---|---|
| No.1 | Hot rolled, annealed & pickled | Original industrial surface | Pressure vessels, industrial equipment |
| 2B | Cold rolled, bright finish | Smooth, reflective | General fabrication |
| BA | Bright annealed | Mirror-like reflectivity | Decorative applications |
| No.4 | Brushed | Matte, fine satin finish | Architectural, food processing |
| HL | Hairline | Continuous linear streaks | Building facades |
| 8K | Mirror | Highly reflective | Luxury finishes |
Chemical Composition (UNS S32750)
| Element | Content (%) |
|---|---|
| Carbon (C) | ≤0.030 |
| Chromium (Cr) | 24.0 – 26.0 |
| Nickel (Ni) | 6.0 – 8.0 |
| Molybdenum (Mo) | 3.0 – 5.0 |
| Manganese (Mn) | ≤1.20 |
| Silicon (Si) | ≤0.80 |
| Nitrogen (N) | 0.24 – 0.32 |
| Copper (Cu) | ≤0.50 |
| Phosphorus (P) | ≤0.035 |
| Sulfur (S) | ≤0.020 |
| Iron (Fe) | Balance |
PREN (Pitting Resistance Equivalent Number) = %Cr + 3.3×%Mo + 16×%N ≥ 42
Mechanical Properties
| Property | Value |
|---|---|
| Tensile Strength (min) | ≥795 MPa (115 ksi) |
| Yield Strength (0.2% offset, min) | ≥550 MPa (80 ksi) |
| Elongation (min) | 15% – 25% |
| Hardness (max) | 310 HB / 32 HRC |
| Density | 7.75 – 7.8 g/cm³ (0.281 lb/in³) |
| Modulus of Elasticity | 200 GPa (29.0 × 10⁶ psi) |
| Melting Point | 1350°C (2460°F) |
Corrosion Resistance Highlights
| Corrosion Type | Performance |
|---|---|
| Pitting / Crevice | PREN ≥42 → excellent resistance in chloride-rich environments; superior to 316L and 2205 |
| Stress Corrosion Cracking (SCC) | Highly resistant in chloride and H₂S environments; NACE MR0175 compliant |
| General Corrosion | Superior to 304/316/317L in acids (sulfuric, formic, acetic) |
| Intergranular Corrosion | Low carbon content prevents sensitization |
| Seawater Resistance | Outstanding; withstands long-term exposure without significant corrosion |
Processing Guidelines
Hot Working
Temperature range: 1875–2150°F (1024–1177°C), followed by rapid cooling.
Cold Working
Requires a higher forming force compared to austenitic grades due to higher strength and hardness.
Heat Treatment
-
Annealing: 1900–2100°F (1038–1149°C)
-
Hardening: Not hardenable by heat treatment; only through cold working
Welding
-
Suitable with standard methods (SMAW, GTAW, GMAW)
-
Recommended filler metal: E2594-17 for super duplex grades
-
Control heat input to maintain phase balance and prevent intermetallic precipitation
-
Post-weld annealing is recommended for stress relief in critical applications
Contact Us
Get a fast, accurate quote for Duplex 2207 Stainless Steel Plates tailored to your project requirements.
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.