Product Description
2205 (S32205/S31803) is a premium duplex stainless steel with a balanced microstructure of approximately 50% austenite and 50% ferrite when properly heat treated. This nitrogen-enhanced alloy combines excellent corrosion resistance with high mechanical strength, making it one of the most widely used duplex stainless steel grades globally. The high chromium (22-23%), molybdenum (2.5-3.5%), nickel (4.5-6.5%), and nitrogen (0.14-0.20%) content provides superior resistance to pitting, crevice corrosion, stress corrosion cracking, and general corrosion in aggressive environments.
2205 duplex stainless steel offers nearly twice the yield strength of conventional austenitic stainless steels like 316L, allowing for reduced wall thickness in pressure vessels and structural applications. Its superior chloride resistance makes 2205 an excellent choice for environments where traditional austenitic grades would fail, particularly in marine and chloride-containing conditions. The optimized chemical composition of 2205 provides a Pitting Resistance Equivalent Number (PREN) of approximately 35, significantly higher than 316L or 317L austenitic stainless steels.
FUSHUN METAL supplies premium quality 2205 duplex stainless steel that offers outstanding performance in a wide range of industries, including chemical processing, oil and gas, marine engineering, pulp and paper production, food processing, and environmental control systems. The combination of high strength, excellent corrosion resistance, and good fabricability makes 2205 an economical choice for applications where both performance and long service life are critical requirements.
Applications
2205 duplex stainless steel is specifically engineered for applications requiring a combination of high strength and superior corrosion resistance, particularly in chloride-containing environments. Its unique properties make it the material of choice for numerous demanding applications across various industries:
- Chemical Processing: Pressure vessels, storage tanks, piping systems, heat exchangers, and reactors handling aggressive chemicals. The high corrosion resistance and strength of 2205 make it ideal for processing equipment exposed to acids, chlorides, and other corrosive media.
- Oil and Gas Production: Flowlines, process piping, separators, heat exchangers, and offshore platform components. 2205 offers excellent resistance to sour gas environments (H₂S) and chloride-containing production fluids combined with high mechanical strength required for high-pressure applications.
- Marine and Offshore: Structural components, platforms, seawater systems, desalination equipment, and propeller shafts. The exceptional resistance to seawater corrosion and high strength-to-weight ratio make 2205 an excellent choice for marine environments.
- Pulp and Paper Industry: Digesters, bleach washers, stock handling systems, and pulp storage tanks. 2205 provides superior resistance to the corrosive chloride-containing chemicals used in pulp processing operations.
- Environmental Control: Flue gas desulfurization (FGD) systems, scrubbers, and pollution control equipment handling acidic and chloride-containing environments.
- Food and Beverage: Processing equipment, storage tanks, and transportation systems where high corrosion resistance and strength are required for handling acidic food products and cleaning solutions.
- Transportation: Cargo tanks for ships and trucks transporting corrosive chemicals or products, where the combination of high strength and corrosion resistance allows for reduced wall thickness and weight savings.
- Structural Applications: Bridge components, support structures in aggressive environments, and architectural applications exposed to marine or industrial atmospheres.
The combination of high strength, excellent corrosion resistance, and good fabricability makes 2205 duplex stainless steel an economical choice for a wide range of applications where conventional austenitic stainless steels would be inadequate, while often eliminating the need for more expensive nickel-based alloys or specialty stainless steels.
Standards
2205 duplex stainless steel conforms to numerous international standards and specifications, ensuring consistent quality and performance in demanding applications:
American Standards:
- ASTM A240/ASME SA240: Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
- ASTM A276/ASME SA276: Standard Specification for Stainless Steel Bars and Shapes
- ASTM A479/ASME SA479: Standard Specification for Stainless Steel Bars and Shapes for Use in Boilers and Other Pressure Vessels
- ASTM A789/ASME SA789: Standard Specification for Seamless and Welded Ferritic/Austenitic Stainless Steel Tubing for General Service
- ASTM A790/ASME SA790: Standard Specification for Seamless and Welded Ferritic/Austenitic Stainless Steel Pipe
- ASTM A182/ASME SA182: Standard Specification for Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Forged Fittings, and Valves and Parts for High-Temperature Service (Grade F51)
- ASTM A815/ASME SA815: Standard Specification for Wrought Ferritic, Ferritic/Austenitic, and Martensitic Stainless Steel Piping Fittings
- ASTM A928/ASME SA928: Standard Specification for Ferritic/Austenitic (Duplex) Stainless Steel Pipe Electric Fusion Welded with Addition of Filler Metal
- ASTM A923: Standard Test Methods for Detecting Detrimental Intermetallic Phase in Duplex Austenitic/Ferritic Stainless Steels
European Standards:
- EN 10088-3: Stainless steels – Part 3: Technical delivery conditions for semi-finished products, bars, rods and sections for general purposes (1.4462)
- EN 10028-7: Flat products made of steels for pressure purposes – Part 7: Stainless steels
- EN 10216-5: Seamless steel tubes for pressure purposes – Technical delivery conditions – Part 5: Stainless steel tubes
- EN 10217-7: Welded steel tubes for pressure purposes – Technical delivery conditions – Part 7: Stainless steel tubes
International Standards:
- ISO 15156/NACE MR0175: Materials for use in H₂S-containing environments in oil and gas production
- NORSOK M-630: Material data sheets and element data sheets for piping
These comprehensive standards ensure that 2205 duplex stainless steel from FUSHUN METAL meets the rigorous requirements for use in critical applications across various industries, particularly where high strength and exceptional corrosion resistance are essential.
Material Designation and Chemical Composition
2205 duplex stainless steel is known by various designations in different standards and specification systems:
| Standard System | Designation |
|---|---|
| UNS | S31803 / S32205 |
| EN | 1.4462 |
| EN Name | X2CrNiMoN22-5-3 |
| ASTM | F51 |
| BS | 318S13 |
| Swedish SS | 2377 |
| Japanese JIS | SUS329J3L |
| AFNOR | Z3CND22-05AZ |
Note: S32205 is a refined composition range of S31803 with more restricted chemistry, providing better guaranteed corrosion resistance. Much of the S31803 currently produced also complies with S32205 requirements.
The chemical composition of 2205 duplex stainless steel is carefully controlled to ensure optimal performance in demanding environments:
| Element | S31803 (%) | S32205 (%) |
|---|---|---|
| Carbon (C) | 0.03 max | 0.03 max |
| Manganese (Mn) | 2.00 max | 2.00 max |
| Phosphorus (P) | 0.03 max | 0.03 max |
| Sulfur (S) | 0.02 max | 0.02 max |
| Silicon (Si) | 1.00 max | 1.00 max |
| Chromium (Cr) | 21.0-23.0 | 22.0-23.0 |
| Nickel (Ni) | 4.5-6.5 | 4.5-6.5 |
| Molybdenum (Mo) | 2.5-3.5 | 3.0-3.5 |
| Nitrogen (N) | 0.08-0.20 | 0.14-0.20 |
| Iron (Fe) | Balance | Balance |
The high levels of chromium, molybdenum, and nitrogen in 2205 result in a Pitting Resistance Equivalent Number (PREN = %Cr + 3.3 × %Mo + 16 × %N) of approximately 35, providing exceptional resistance to localized corrosion in aggressive environments. The balanced chemical composition ensures an optimal dual-phase microstructure with approximately equal proportions of austenite and ferrite for superior mechanical properties and corrosion resistance.
Physical and Mechanical Properties
2205 duplex stainless steel offers an exceptional combination of high strength and excellent corrosion resistance, making it ideal for demanding applications where conventional stainless steels would be inadequate.
Mechanical Properties
The mechanical properties of 2205 are significantly superior to those of conventional austenitic stainless steels:
| Property | S31803 Specification | S32205 Specification | Typical Values |
|---|---|---|---|
| Ultimate Tensile Strength | 90 ksi (620 MPa) min | 95 ksi (655 MPa) min | 105 ksi (725 MPa) |
| 0.2% Yield Strength | 65 ksi (450 MPa) min | 65 ksi (450 MPa) min | 74 ksi (510 MPa) |
| Elongation in 2″ (50 mm) | 25% min | 25% min | 30% |
| Hardness | 290 HBW max (31 HRC max) | 290 HBW max (31 HRC max) | 260 HBW (19 HRC) |
| Impact Energy at 20°C | 100 J min | 100 J min | 270 J |
Physical Properties
| Property | Value |
|---|---|
| Density | 0.278 lb/in³ (7.8 g/cm³) at 68°F (20°C) |
| Melting Range | 2525-2630°F (1385-1443°C) |
| Modulus of Elasticity at 68°F (20°C) | 29 × 10⁶ psi (200 GPa) |
| Thermal Conductivity at 68°F (20°C) | 8.7 BTU/h·ft·°F (15 W/m·K) |
| Coefficient of Thermal Expansion (68-212°F/20-100°C) | 7.5 × 10⁻⁶ /°F (13.7 × 10⁻⁶ /°C) |
| Specific Heat at 68°F (20°C) | 0.112 BTU/lb·°F (500 J/kg·K) |
| Electrical Resistivity | 33.5 × 10⁻⁶ Ω·in (0.80 Ω·mm²/m) |
| Magnetic Permeability | Ferromagnetic |
ASME Maximum Allowable Stress Values
The high strength of 2205 is reflected in its ASME maximum allowable stress values, which are significantly higher than those for conventional austenitic stainless steels:
| Temperature, °F (°C) | 2205 (ksi) | 316L (ksi) | 317L (ksi) |
|---|---|---|---|
| 200 (93) | 25.7 | 20.0 | 17.0 |
| 300 (149) | 24.8 | 20.0 | 15.2 |
| 400 (204) | 23.9 | 19.3 | 14.0 |
| 500 (260) | 23.3 | 18.0 | 13.1 |
| 600 (316) | 23.1 | 17.0 | 12.5 |
Corrosion Resistance
2205 duplex stainless steel offers exceptional resistance to various forms of corrosion:
- Pitting and Crevice Corrosion: Superior resistance to localized corrosion in chloride-containing environments, with a Critical Pitting Temperature (CPT) significantly higher than 316L and 317L stainless steels.
- Stress Corrosion Cracking: Excellent resistance to chloride stress corrosion cracking, making it suitable for applications where conventional austenitic stainless steels would fail.
- General Corrosion: Superior resistance to uniform corrosion in a wide range of environments, including organic and inorganic acids.
- Erosion Corrosion: High hardness and corrosion resistance provide good protection against erosion-corrosion in flowing media.
- Corrosion Fatigue: Excellent resistance to corrosion fatigue due to its high strength and corrosion resistance.
Heat Treatment
To achieve optimal properties, 2205 duplex stainless steel requires proper heat treatment:
- Solution Annealing: Heating to 1900-2100°F (1040-1150°C) followed by rapid cooling, preferably by water quenching. This treatment ensures the proper phase balance and dissolves any detrimental intermetallic phases.
- Stress Relief: If required, full solution annealing is recommended rather than lower-temperature stress relief treatments, which may lead to precipitation of deleterious phases.
- Temperature Limitations: 2205 duplex stainless steel should generally be limited to service temperatures between -50°F (-46°C) and 600°F (315°C) to avoid low-temperature embrittlement or high-temperature phase precipitation.
The microstructure and mechanical properties of 2205 can be affected by prolonged exposure to temperatures between 600°F (315°C) and 1800°F (980°C), which can lead to the precipitation of sigma phase and other intermetallic compounds that reduce toughness and corrosion resistance. For this reason, 2205 is not recommended for continuous service above 600°F (315°C).
Available Dimensions
FUSHUN METAL offers 2205 duplex stainless steel in a comprehensive range of product forms and dimensions to meet diverse application requirements:
Plate and Sheet
| Product Form | Thickness | Width | Length |
|---|---|---|---|
| Plate | 4.0 mm – 150 mm (0.157″ – 6″) | Up to 3,000 mm (120″) | Up to 12,000 mm (480″) |
| Sheet | 0.5 mm – 4.0 mm (0.020″ – 0.157″) | Up to 1,500 mm (60″) | Up to 6,000 mm (240″) |
Bar and Rod
| Product Form | Diameter/Dimension | Length |
|---|---|---|
| Round Bar | 5 mm – 300 mm (0.197″ – 12″) | Up to 6,000 mm (240″) |
| Square Bar | 10 mm – 200 mm (0.394″ – 8″) | Up to 6,000 mm (240″) |
| Flat Bar | Thickness: 5 mm – 50 mm (0.197″ – 2″) Width: 10 mm – 300 mm (0.394″ – 12″) |
Up to 6,000 mm (240″) |
| Hexagonal Bar | 10 mm – 100 mm (0.394″ – 4″) across flats | Up to 6,000 mm (240″) |
Pipe and Tube
| Product Form | Outside Diameter | Wall Thickness | Length |
|---|---|---|---|
| Seamless Pipe | 6 mm – 508 mm (0.236″ – 20″) | Schedule 5S – XXS | Up to 12,000 mm (472″) |
| Welded Pipe | 6 mm – 1,219 mm (0.236″ – 48″) | Schedule 5S – XXS | Up to 12,000 mm (472″) |
| Seamless Tube | 6 mm – 50.8 mm (0.236″ – 2″) | 0.5 mm – 6.4 mm (0.020″ – 0.250″) | Up to 25,000 mm (984″) |
| Welded Tube | 6 mm – 219 mm (0.236″ – 8.625″) | 0.5 mm – 6.4 mm (0.020″ – 0.250″) | Up to 25,000 mm (984″) |
Fittings and Flanges
FUSHUN METAL also provides a wide range of fittings and flanges in 2205 duplex stainless steel:
- Butt-weld fittings: elbows, tees, reducers, caps (ASTM A815)
- Threaded fittings (ASTM A182)
- Socket-weld fittings (ASTM A182)
- Flanges: slip-on, weld neck, blind, socket weld, threaded (ASTM A182)
Custom dimensions and special profiles can be produced to meet specific customer requirements. Please contact our sales team for more information about non-standard sizes and special specifications.
Fabrication Information
2205 duplex stainless steel can be successfully fabricated using conventional methods, but there are some important considerations to ensure optimal performance of the finished components:
Forming
Due to its high strength, forming of 2205 requires more force than austenitic stainless steels:
- Hot Forming: Should be performed in the temperature range of 1750-2250°F (950-1230°C). Material must be uniformly heated and worked within this range to avoid cracking. Hot forming operations should be followed by solution annealing and rapid cooling.
- Cold Forming: 2205 can be readily cold formed, but requires about 50-60% more force than austenitic stainless steels due to its higher strength. The minimum inner bend radius for 2205 is typically 3-4 times the material thickness. Spring-back is greater than with austenitic stainless steels and should be compensated for during forming.
- Post-forming Heat Treatment: Solution annealing is recommended after significant cold forming (>10% deformation) to restore the optimal microstructure and properties.
Welding
2205 has good weldability but requires specific procedures to maintain optimal properties:
- Filler Metal: E2209 or ER2209 filler metals should be used to ensure proper phase balance in the weld.
- Heat Input: Should be kept between 0.5-2.5 kJ/mm. Excessive heat input can lead to ferrite formation, while insufficient heat input can result in excessive ferrite and reduced corrosion resistance.
- Interpass Temperature: Should be limited to 300°F (150°C) maximum to avoid the formation of intermetallic phases.
- Shielding Gas: Pure argon or argon-based mixtures with 1-3% nitrogen addition are recommended. The nitrogen addition helps maintain the austenite-ferrite balance in the weld metal.
- Preheating: Generally not required unless the material temperature is below 50°F (10°C) to prevent condensation.
- Post-weld Heat Treatment: Not normally required for corrosion resistance if proper welding procedures are followed. If necessary, solution annealing at 1900-2100°F (1040-1150°C) followed by rapid cooling is recommended.
Machining
Due to its high strength and work hardening rate, machining of 2205 requires special considerations:
- Cutting speeds should be approximately 20% lower than those used for austenitic stainless steels like 304 or 316.
- Rigid tooling setups and powerful machines are essential.
- Tools should have large rake angles, sharp cutting edges, and smooth surfaces.
- Relatively large feed rates and cutting depths are recommended to minimize work hardening of the surface layer.
- Adequate cooling is essential to prevent overheating and tool wear.
Surface Finishing
2205 can be finished using standard methods for stainless steels:
- Mechanical polishing
- Electropolishing
- Passivation
- Pickling
Proper cleaning and passivation after fabrication are important to ensure optimal corrosion resistance, particularly after welding or other thermal processes that may affect the surface condition.
Why Choose FUSHUN METAL for 2205 Duplex Stainless Steel
When selecting a supplier for premium 2205 duplex stainless steel, FUSHUN METAL stands as your preferred partner for several compelling reasons:
Superior Quality Assurance
At FUSHUN METAL, we implement rigorous quality control processes throughout our production chain. Our 2205 duplex stainless steel undergoes comprehensive testing including chemical analysis, mechanical testing, metallographic examination, and corrosion testing to ensure full compliance with international standards and specifications. We verify the absence of detrimental intermetallic phases in accordance with ASTM A923, guaranteeing that our products will consistently deliver the exceptional performance required in the most demanding applications.
Metallurgical Expertise
Our team of metallurgical specialists possesses extensive experience and knowledge in the production and processing of duplex stainless steels. This expertise enables us to provide valuable technical support to help you select the optimal material specifications for your specific application requirements. We understand the critical factors that influence the performance of 2205 duplex stainless steel and can help you optimize your designs to take full advantage of its superior properties.
Comprehensive Product Range
FUSHUN METAL offers one of the most extensive ranges of 2205 duplex stainless steel products available, including plate, sheet, bar, pipe, tube, fittings, flanges, and custom components. This diverse product portfolio allows you to source all your duplex stainless steel requirements from a single, reliable supplier, streamlining your procurement process and ensuring consistency across your projects.
Advanced Processing Capabilities
Our state-of-the-art processing facilities enable us to provide 2205 duplex stainless steel with precise dimensional tolerances, superior surface finishes, and optimal mechanical properties. Whether you need standard products or custom-engineered solutions, our advanced manufacturing capabilities ensure that your materials meet or exceed your expectations.
Value-Added Services
Beyond supplying premium materials, we offer a range of value-added services including custom cutting, machining, heat treatment, surface finishing, and non-standard dimensions to meet your specific requirements. Our ability to provide tailored solutions helps you optimize your manufacturing processes and reduce overall costs.
For your next project requiring the exceptional corrosion resistance and high strength of 2205 duplex stainless steel, we invite you to contact our technical team to discuss your specific requirements. Our experts are ready to help you select the optimal material specifications and provide the premium quality products you need for reliable, long-term performance in even the most challenging environments.
