Duplex 2205
UNS S32205
High-strength duplex stainless steel for corrosive environments, chlorides, marine applications, chemical industry and made-to-drawing CNC machined parts.
A duplex stainless steel for strength and corrosion resistance
Duplex 2205 - UNS S32205 / S31803 is a duplex stainless steel formed by a balanced microstructure of ferrite and austenite.
This combination provides higher mechanical strength than many conventional austenitic stainless steels, together with excellent behaviour against pitting corrosion, crevice corrosion and chloride-containing environments.
Material identification
What is Duplex 2205?
It is a duplex stainless steel that combines ferritic and austenitic phases to offer a strong balance of mechanical strength and corrosion resistance.
Its chromium, molybdenum and nitrogen content improves its behaviour in chloride-containing media, seawater, chemical environments and applications where material durability is critical.
High strength
Higher yield strength than many standard austenitic stainless steels.
Chlorides
Very good behaviour in environments with salts and seawater.
Dual phase
Balanced ferrite and austenite microstructure for high performance.
Industrial use
Applicable in chemical, offshore, desalination, marine, pump and valve sectors.
Why it is used in corrosive environments
Duplex 2205 is selected when the part requires mechanical strength, chloride resistance, dimensional control and service reliability.
| Property | Technical advantage |
|---|---|
| High mechanical strength | Allows the production of components subjected to load, pressure or structural stress. |
| Pitting resistance | Good behaviour in the presence of chlorides, salts and aggressive media. |
| Crevice corrosion resistance | Interesting for joints, complex geometries and accumulation areas. |
| Stress corrosion cracking | Greater resistance to chloride-related problems in critical applications. |
| Fatigue | Favourable behaviour compared with conventional stainless steels under certain conditions. |
| Weight optimisation | Its high yield strength may allow reduced thicknesses in some designs. |
A chemistry designed for chloride resistance
The performance of Duplex 2205 is based on a composition with chromium, nickel, molybdenum and nitrogen.
Chromium contributes to corrosion resistance, molybdenum improves behaviour against pitting and crevice corrosion, while nitrogen increases mechanical strength and helps stabilise the duplex structure.
Approximate chemical composition
High strength for demanding parts
Its mechanical values make Duplex 2205 a very interesting option for components subjected to stress and corrosive environments.
Tensile strength
Yield strength
Elongation
Approximate hardness
Where Duplex 2205 is used
This material is used in sectors where corrosion, chlorides, pressure and component durability are critical factors.
Chemical industry
Petrochemical
Oil & gas
Offshore
Desalination
Water treatment
Pumps and valves
Heat exchangers
CNC machining of Duplex 2205
Machining Duplex 2205 requires control of cutting strategy, cooling, tool wear and dimensional stability.
At AREM-CNC, we manufacture parts in duplex stainless steels from drawings, physical samples or technical specifications, adapting the process to the material, geometry, tolerances, finish and required documentation.
Made-to-drawing production
- Special screws and studs.
- Precision machined nuts.
- Washers, bushings and technical spacers.
- Shafts, pins and custom components.
- Flanges, plugs, rings and industrial parts.
- Components for pumps, valves and chemical systems.
Common material references
Duplex 2205 can appear in drawings, certificates and technical orders under different equivalent designations.
Technical documentation for duplex steels
In duplex materials, traceability allows control of composition, batch, heat number, certificate and suitability of the material for the application.
Depending on the project, we can work with material certificates, heat numbers, dimensional control, technical drawings, tolerances, surface finish and final documentation associated with manufacturing.
Frequently asked questions about Duplex 2205
What is Duplex 2205?
It is a duplex stainless steel identified as UNS S32205 / S31803, with a balanced microstructure of ferrite and austenite.
Where is Duplex 2205 used?
It is used in the chemical industry, petrochemical industry, offshore, desalination, water treatment, marine applications, pumps, valves and heat exchangers.
What advantage does it offer over standard stainless steels?
It offers higher mechanical strength and better behaviour against chlorides, pitting corrosion and stress corrosion cracking than many conventional stainless steels.
Can made-to-drawing CNC parts be manufactured in Duplex 2205?
Yes. CNC machining can be used to manufacture screws, nuts, washers, bushings, shafts, pins, flanges and special made-to-drawing components, provided that the geometry is feasible.
Why is traceability important?
Because in duplex materials it is essential to verify composition, batch, heat number, certificate and technical equivalence of the material used.
Do you need parts manufactured in Duplex 2205?
Send us your drawing, physical sample or technical specification. We will review material, tolerances, geometry, finish and required documentation to manufacture a reliable and traceable solution.