UNS S31803 Duplex Stainless Steel Plate Thickness 0.4 - 60.0mm Hot
Rolled / Cold Rolled Alloy 2205 Stainless
Material to UNS S31803 is described as a duplex stainless steel
with a microstructure of 50:50 austenite and ferrite.
Stainless Duplex UNS S31803 piping Products are less costly
compared to other types of duplex steel material. One of the
reasons is the composition does not have much molybdenum as opposed
to other grades of duplex steel. 22 Cr Duplex UNS S31803 F51 raw
material includes chromium and nickel in mid ranges. This makes the
Duplex UNS S31803 material to perform midway between austenitic
steel types and the super duplex steel types. Duplex SS UNS S31803
material is called the standard duplex steel. This is also the most
commonly used type of duplex due to the low cost and
interchangeability between austenitic steel needs and duplex steel
needs.
GOOD MECHANICAL STRENGTH
The steel combines good mechanical strength (typically up to over
480 MPa yield strength) and ductility with moderate to good
corrosion resistance in a variety of environments. By agreement,
the alloy can be supplied with a PREN (Pitting Resistance
Equivalent) at >34 which ensures that the resistance to pitting
corrosion is as high as possible for this alloy grade. In addition,
the steel offers good resistance to stress corrosion cracking.
Ambient and sub-zero temperature notch ductility is good.
AN ALTERNATIVE TO 300 SERIES STAINLESS STEELS
These attributes mean that this duplex steel can be used
successfully as an alternative to 300 series stainless steels in
applications where higher mechanical strength / lower weight is
required and / or resistance to stress corrosion cracking is
needed.
We stock UNS S31803 in flats, round bar, plate, sheet, round tube,
hollow bar and square bar.
S31803 / F51 is a duplex stainless steel based on a 22% chromium 5%
nickel alloying system. Also known as 2205 this is the most widely
used of the duplex grades and offers a combination of good strength
and ductility and a very high marine corrosion resistance (better
than grades such as 316).
It offers an excellent resistance to intergranular corrosion,
pitting (PREN ≥35) and crevice corrosion combined with a high
resistance to chloride stress corrosion cracking at temperatures up
to ~150ºC. These attributes have enabled it to become a proven
material for many offshore and marine components that have to
operate in critical conditions.
Chemical Composition of UNS S31803 Duplex Stainless Steel
| Iron | Rem |
| Chromium | 22.0% |
| Nickel | 5.5% |
| Manganese | 2.0% max |
| Molybdenum | 3.0% |
Related Specifications
| S32205 | Alloy 2205 |
| EN 1.4462 | F51 |
Key Features of Duplex S31803 Stainless Steel
High strength levels
Very good resistance to pitting & crevice corrosion
High resistance to stress corrosion cracking, fatigue and erosion
Excellent resistance to chloride stress corrosion cracking
Good workability and weldability
Typical Physical Properties
| Melting Point | 1440°C |
| Density | 7.8 g/cm³ |
| Thermal conductivity | 17.0 W/m°K |
| Thermal expansion coefficient | 14.0 x 10-6 |
| Electrical resistivity | 80 microhm-cm |
| Specific Heat (20°C) | 425 J/Kg °C |
| Modulus of Elasticity | 200 GPa |
| Magnetic Permeability | 33 |
Fabrication Properties
| Hot Forming temperature | 1149-1260°C |
| Machinability | Okay |
| Oxy-acetylene welding | Not recommended |
| Gas-shielded arc welding | Good |
| Resistance welding | Good |
Typical Applications
S31803 / F51 stainless has been used for components in food
processing, power generation, paper and pulp industry, chemical
processing and for offshore and marine activities. Components
include pipework, high strength fasteners, wellhead and subsea
wellhead fittings, desalination plant, seawater cooled heat
exchanger, chemical tanks, flue gas filters and acetic acid
distillation components.
This technical information is given by Holme Dodsworth Metals
without charge and the user shall employ such information at their
own discretion and risk. For more detailed technical advice on
temper selection, fabrication, joining, machining, physical and
mechanical data please contact us as space does not permit the
listing of every feature of the material.
