What is 1.4462 Stainless Steel?

1.4462 stainless steel, commonly known as Duplex 2205 or UNS S32205, is a ferritic-austenitic duplex stainless steel that combines the beneficial properties of both phases. It offers approximately twice the yield strength of standard austenitic stainless steels and excellent resistance to stress corrosion cracking, pitting, and crevice corrosion, making it ideal for demanding applications in chemical processing, oil and gas, marine, and pulp and paper industries.

 

This duplex grade is standardized under key international systems.

Standard	Equivalent Grade
EN (Europe)	1.4462
ASTM/AISI (USA)	2205, UNS S32205
JIS (Japan)	SUS329J3L

Its balanced composition provides a roughly 50/50 ferritic-austenitic microstructure.

Element	C	Si	Mn	P	S	Cr	Ni	Mo	N
Content (%)	≤ 0.03	≤ 1.0	≤ 2.0	≤ 0.035	≤ 0.02	21.0 - 23.0	4.5 - 6.5	2.5 - 3.5	0.10 - 0.22

It offers high strength along with good toughness and corrosion resistance.

Property	Yield Strength (Rp0.2)	Tensile Strength (Rm)	Elongation (A)	Hardness (HB)	Impact (J)
Typical Value	≥ 450 MPa	620 - 880 MPa	≥ 25%	≤ 293	≥ 100

 

Key Characteristics and Applications of 1.4462 / Duplex 2205

High Strength and Excellent Fatigue Resistance: The duplex structure provides high yield strength, allowing for thinner, lighter structures and components.

Outstanding Corrosion Resistance: Offers excellent resistance to pitting, crevice corrosion, and stress corrosion cracking (SCC), especially in chloride environments.

Good Weldability: Can be welded using common techniques, though care must be taken to maintain the balanced microstructure in the weld zone.

 

Primary Applications:

Oil & Gas: Pressure vessels, pipelines, heat exchangers, and offshore platform components.

Chemical & Petrochemical: Tanks, reactors, and piping systems handling corrosive media.

Pulp & Paper Industry: Digesters, bleaching equipment.

Marine & Offshore: Seawater piping systems, propeller shafts, and desalination plants.

 

How does Duplex 2205 (1.4462) compare to 316L (1.4404) in terms of performance?
Duplex 2205 offers approximately twice the yield strength of 316L, providing significant weight-saving potential in structural designs. It also demonstrates superior resistance to stress corrosion cracking (SCC) in chloride environments. While both have good pitting resistance, 2205 generally has a higher Pitting Resistance Equivalent Number (PREN), making it suitable for more aggressive conditions than 316L.

 

What are the key considerations when welding 1.4462 duplex stainless steel?
The primary goal is to preserve the balanced 50/50 ferrite-austenite microstructure in the weld and heat-affected zone. This requires using matching or over-alloyed filler metals, controlling heat input to avoid excessive grain growth, and ensuring proper shielding to prevent nitrogen loss. Post-weld cooling rate is also critical to avoid the formation of detrimental intermetallic phases.

 

Looking for a Reliable Supplier of 1.4462 / Duplex 2205 Stainless Steel?
GNEE Steel supplies high-quality Duplex 2205 (1.4462) stainless steel in plate, pipe, and bar forms. We support your projects with processing services and provide full material certification to ensure compliance with international standards. If you have any requirements, please feel free to contact us.