S32760 Super Duplex Stainless Steel, also known as UNS S32760 (Zeron 100), is a high-performance alloy specifically developed for extreme corrosive and high-stress environments. Featuring a balanced austenitic–ferritic microstructure, S32760 delivers an outstanding combination of high mechanical strength and superior corrosion resistance.
With elevated levels of chromium, molybdenum, nitrogen, and copper, S32760 achieves a PREN value exceeding 40, providing excellent resistance to pitting and crevice corrosion in chloride-rich and acidic environments. This makes it a preferred material for critical industrial applications where standard stainless steels are insufficient.
Properties of S32760 Material
- Exceptional resistance to pitting, crevice corrosion, and stress corrosion cracking (SCC)
- Excellent performance in seawater and chloride-containing environments
- High yield strength, approximately twice that of austenitic stainless steels
- Good weldability when proper welding procedures are followed
- Long service life in aggressive and demanding conditions
S32760 Super Duplex Stainless Steel — Equivalent Materials
| Standard | Equivalent Material | Notes |
| UNS | S32760 | Original designation |
| EN / DIN | 1.4501 / X2CrNiMoCuWN25-7-4 | European / German standard |
| ASTM / ASME | ASTM A182 F53 | Standardized forged alloy |
| NORSOK M-630 | S32760 | Oil & gas industry compliance |
| Chinese GB | Zeron 100 | Often used in Asian markets |
| Other Super Duplex | SAF 2507 | Similar composition, slightly lower Mo content |
| F53 / F55 | Widely used in chemical & marine applications |
Chemical Composition and Metallurgical Advantages
| Element | C | Mn) | Si | P | S | Cr | Ni | Mo | Cu | N | Fe |
| Content Range | ≤ 0.03 | ≤ 1.00 | ≤ 1.00 | ≤ 0.030 | ≤ 0.010 | 24.0 – 26.0 | 6.0 – 8.0 | 3.0 – 4.0 | 0.5 – 1.0 | 0.20 – 0.30 | Balance |
The superior performance of S32760 is derived from its optimized alloy composition:
- High chromium and molybdenum content for enhanced corrosion resistance
- Nitrogen addition to improve strength and pitting resistance
- Copper addition for improved resistance in acidic media
The dual-phase microstructure ensures a balanced combination of toughness, strength, and corrosion resistance.
Mechanical Properties (Forged Condition)
| Property | Tensile Strength | Yield Strength (0.2%) | Elongation | Hardness | Impact Toughness (-46°C) | Density |
| Typical Value | ≥ 750 MPa | ≥ 550 MPa | ≥ 15% | ≤ 290 HB (~ ≤ 31 HRC) | ≥ 40 J (typical, per spec) | ~7.8 g/cm³ |
Applications of S32760 Super Duplex Stainless Steel
- Offshore and marine engineering
- Oil and gas production and processing
- Chemical and petrochemical industries
- Seawater desalination systems
- Heat exchangers, pumps, and valves
S32760 vs SAF 2507 vs F53 vs 2205 — Super Duplex Stainless Steel Comparison
| Feature / Grade | S32760 (UNS S32760 / Zeron 100) | SAF 2507 | F53 | 2205 (UNS S31803 / S32205) |
| Type | Super Duplex | Super Duplex | Super Duplex | Duplex |
| Chromium (Cr) | 24–26% | 25% | 24–25% | 22–23% |
| Nickel (Ni) | 6–8% | 7% | 6–7% | 4–6% |
| Molybdenum (Mo) | 3–4% | 3.60% | 3–3.5% | 3% |
| Nitrogen (N) | 0.20–0.30% | 0.30% | 0.20% | 0.14–0.20% |
| Copper (Cu) | 0.5–1.0% | 0.50% | 0.50% | <0.5% |
| PREN (Pitting Resistance) | >40 | ~40 | 38–40 | 32–34 |
| Yield Strength (MPa) | 550–700 | 550–700 | 550–700 | 450–550 |
| Tensile Strength (MPa) | 750–900 | 750–900 | 750–850 | 620–800 |
| Temperature Limit (°C) | Up to 300 | Up to 300 | Up to 300 | Up to 250 |
| Corrosion Resistance | Excellent, best in super duplex class | Excellent | Excellent | Very good |
| Applications | Offshore, oil & gas, chemical, seawater | Offshore, chemical, seawater | Chemical, marine, desalination | General industrial, chemical, marine |
When selecting high-performance stainless steel for offshore, marine, or chemical environments, understanding the differences between S32760, SAF 2507, F53, and 2205 is critical.
- S32760 (Zeron 100): Highest corrosion resistance and strength, PREN > 40, ideal for extreme chloride and H₂S environments.
- SAF 2507: Comparable to S32760, widely used in offshore and chemical applications.
- F53: Excellent corrosion resistance for chemical and desalination industries.
- 2205: Standard duplex steel, suitable for moderate corrosion environments.
Choosing the right grade ensures long-term reliability, safety, and reduced maintenance costs. Super duplex grades like S32760 and SAF 2507 are preferred for critical, high-pressure, and highly corrosive industrial applications.
Conclusion
S32760 Super Duplex Stainless Steel is a high-strength, corrosion-resistant alloy designed for the most demanding industrial environments, including offshore, oil & gas, chemical, and marine applications. With its superior pitting and crevice corrosion resistance (PREN > 40), excellent mechanical properties, and robust dual-phase microstructure, S32760 outperforms standard duplex steels like 2205 and is ideal for critical, high-pressure, and highly corrosive service conditions, providing long-term reliability and reduced maintenance costs.
