Stainless Steel - Duplex - 1.4462 Sheet and Plate

1.4462 Sheet and Plate

Duplex stainless steels are extremely corrosion resistant, work hardenable alloys. Their microstructures consist of a mixture of austenite and ferrite phases. As a result, duplex stainless steels display properties characteristic of both austenitic and ferritic stainless steels. This combination of properties can mean some compromise when compared with pure austenitic and pure ferritic grades.
Duplex stainless steels are in most cases, tougher than ferritic stainless steels. Strengths of duplex stainless steels can in some cases be double that for austenitic stainless steels.
Whilst duplex stainless steels are considered resistant to stress corrosion cracking, they are not as resistant to this form of attack as ferritic stainless steels. However, the corrosion resistance of the least resistant duplex stainless steels is greater than that for the most commonly used grades of stainless steels, i.e. 304 and 316.
Duplex steels are also magnetic, a property that can be used to easily differentiate them from common austenitic grades of stainless.
Property data given in this document is typical for flat rolled products covered by ASTM A240/A240M. ASTM, EN or other standards may cover products sold. It is reasonable to expect specifications in these standards to be similar but not necessarily identical to those given in this datasheet.


Chemical Composition

Chemical Element % Present
Carbon (C) 0.0 - 0.03
Chromium (Cr) 21.00 - 23.00
Manganese (Mn) 2.00 max
Silicon (Si) 1.00 max
Phosphorous (P) 0.0 - 0.03
Sulphur (S) 0.0 - 0.02
Nickel (Ni) 4.50 - 6.50
Nitrogen (N) 0.08 - 0.20
Molybdenum (Mo) 2.50 - 3.50
Iron (Fe) Balance

Properties

Physical PropertyValue
Density 7.805 g/cm³
Thermal Expansion 13.7 x10^-6 /K
Modulus of Elasticity 200 GPa
Thermal Conductivity 19.0 W/m.K
Electrical Resistivity 0.085 x10^-6 Ω .m
Mechanical PropertyValue
Proof Stress 450 Min MPa
Tensile Strength 620 Min MPa
Elongation A50 mm 25 Min %
Hardness Brinell 290 Max HB
Values listed above are for 1.4462 sheet / Plate

Alloy Designations

Grade 1.4462/2205 is similar to but may not be a direct equivalent:

UNS S31803

UNS S32205

BS 318S13


Supplied Forms

  • Fittings & Flanges
  • Pipe
  • Plate
  • Sheet
  • Tube
  • Bar

Applications

Duplex stainless steels are typically used in:

~ Chemical processing, transport and storage

~ Oil and gas exploration and offshore rigs

~ Oil and gas refining

~ Marine environments

~ Pollution control equipment

~ Pulp & paper manufacturing

~ Chemical process plant


Corrosion Resistance

Duplex stainless steels are extremely corrosion resistant. They have high resistance to intergranular corrosion. Even in chloride and sulphide environments, duplex stainless steels exhibit very high resistance to stress corrosion cracking.

The super duplex grades are even more resistant to corrosion.


Heat Resistance

 

The high chromium content of duplex stainless steels that protects against corrosion, causes embrittlement at temperatures over about 300°C.

At low temperatures duplex stainless steels have better ductility than the ferritic and martensitic grades. Duplex grades can readily  be used down to at least -50°C.


Fabrication

Fabrication of all stainless steels should be done only with tools dedicated to stainless steel materials. Tooling and work surfaces must be thoroughly cleaned before use. These precautions are necessary to avoid cross contamination of stainless steel by easily corroded metals that may discolour the surface of the fabricated product.


Machinability

Although machinable, the high strengths of duplex stainless steels makes machining difficult. As an example, machining of 2205 is around 20% slower than for 304.

 

Machining can be enhanced by using the following rules:

 

~ Cutting edges must be kept sharp. Dull edges cause excess work hardening.

~ Cuts should be light but deep enough to prevent work hardening by riding on the surface of the material.

~ Chip breakers should be employed to assist in ensuring swarf remains clear of the work

~ Low thermal conductivity of austenitic alloys results in heat concentrating at the cutting edges. This means coolants and lubricants are necessary and must be used in large quantities.


Heat Treatment

Duplex stainless steels cannot be hardened by heat treatment. They can however be work hardened.

Solution treatment or annealing can be done by rapid cooling after heating to around 1100°C.


Weldability

Duplex stainless steels have good weldability. All standard welding processes can be used. They are not quite as easily welded as the austenitic grades but low thermal expansion in duplex grades reduces distortion and residual stresses after welding. The recommended filler material for 2205 stainless steel is 2209.

Datasheet Search

Last Datasheet Revision

27 January 2014

Disclaimer

This Data is indicative only and as such is not to be relied upon in place of the full specification. In particular, mechanical property requirements vary widely with temper, product and product dimensions. All information is based on our present knowledge and is given in good faith. No liability will be accepted by the Company in respect of any action taken by any third party in reliance thereon.

Please note that the 'Datasheet Update' date shown above is no guarantee of accuracy or whether the datasheet is up to date.

The information provided in this datasheet has been drawn from various recognised sources, including EN Standards, recognised industry references (printed & online) and manufacturers’ data. No guarantee is given that the information is from the latest issue of those sources or about the accuracy of those sources.

Material supplied by the Company may vary significantly from this data, but will conform to all relevant and applicable standards.

As the products detailed may be used for a wide variety of purposes and as the Company has no control over their use; the Company specifically excludes all conditions or warranties expressed or implied by statute or otherwise as to dimensions, properties and/or fitness for any particular purpose, whether expressed or implied.

Advice given by the Company to any third party is given for that party’s assistance only and without liability on the part of the Company. All transactions are subject to the Company’s current Conditions of Sale. The extent of the Company’s liabilities to any customer is clearly set out in those Conditions; a copy of which is available on request.