Chemical Composition

• High chromium (24–26%) and molybdenum (7–8%) for superior resistance to pitting and crevice corrosion.
• Nickel (23–25%) to enhance ductility and stability.
• Copper (0.5–1.0%) and nitrogen (0.4–0.5%) to improve strength and resistance to chloride-induced stress corrosion cracking (SCC).
• Low carbon content (<0.02%) to prevent sensitization.

Key Properties

1. Corrosion Resistance:
   • Highly resistant to harsh environments, including seawater, chlorides, and acids (e.g., sulfuric and phosphoric acids).
   • Offers a Critical Pitting Temperature (CPT) exceeding 60°C, far higher than standard stainless steels like 316L.
2. Mechanical Strength:
   • Yield strength ≥ 430 MPa and tensile strength ≥ 700 MPa, making it suitable for high-pressure applications.
   • Excellent ductility and impact resistance even at low temperatures.
3. Heat Resistance:
   • Maintains stability in temperatures up to 300°C, with minimal carbide precipitation.

Manufacturing and Fabrication

• Produced via vacuum induction melting (VIM) and electroslag remelting (ESR) for purity.
• Machinable with proper tools and lubrication, though its high strength may require increased cutting forces.
• Weldable using techniques like TIG or MIG, with matching filler metals (e.g., ERNiCrMo-3) to maintain corrosion resistance.

Applications

• Marine Engineering: Offshore platforms, seawater pipelines, and desalination equipment.
• Chemical/Petrochemical Industry: Reactors, heat exchangers, and vessels handling corrosive media.
• Pharmaceuticals and Food Processing: Equipment requiring high hygiene and corrosion resistance.
• Oil and Gas: Subsea components and high-chloride environments.

Standards and Specifications

• Complies with ASTM A240, EN 10088-2, and ASME SA-240.
• Common designations: UNS S32654, 1.4652.

Advantages Over Other Alloys

• Outperforms 904L and 254 SMO in extreme chloride conditions.
• Reduces maintenance and replacement costs in aggressive environments.
• Suitable for applications where weight and strength are critical (e.g., lightweight structures).