F44 (UNS S31254 / W.Nr. 1.4547)
F44 (UNS S31254 / W.Nr. 1.4547) an austenitic stainless steel used in seawater and other aggressive chloride- bearing media. This grade has excellent resistance to pitting and crevice corrosion, high resistance to general corrosion and stress corrosion cracking, with a higher strength than conventional austenitic stainless steels, and good weldability.
|–||–||F44||S31254||X1CrNiMoCuN20-18-7||1.4547||Z1 CNDU 20.18.06AZ||X1CrNiMoCuN20-18-7||–||–|
Chemical Composition, %
Typical Physical and Mechanical Properties (RT, Annealed)
|Density, g/cm3||Melting Point, ℃||Tensile Strength, MPa||Yield Strength, MPa||ELongation, %||Hardness, HRB|
Available Products and Specifications
|Rod, Bar, Wire and Forgings||ASTM A182|
|Plate, Sheet and Strip||ASTM A312|
|Pipe and Tube||ASTM A167, 240|
The steel combines moderate mechanical strength (typically over 300 MPa yield strength) and high ductility with excellent corrosion resistance in seawater and a variety of industrial environments. Typically the alloy has a PREn (Pitting Resistance Equivalent) of 42-44 which ensures that the resistance to pitting corrosion is high. In addition, the steel provides good resistance to crevice corrosion. Ambient and sub-zero temperature notch ductility is very good. These attributes mean that this high molybdenum stainless steel can be used successfully as an alternative to 300 series austenitic stainless steels (such as type 316) in applications where higher mechanical strength and/or enhanced resistance to pitting and crevice corrosion is required.
Commercial applications for this engineering material include:
- Pipework, flanges & manifolds
- Oil & Gas industry components