SAF 2507® super-duplex stainless steel
SAF 2507® (UNS S32750) is a super-duplex stainless steel; a high-alloy duplex steel with a PRE value of min. 42*. The grade is characterized by very good chloride corrosion resistance, combined with very high mechanical strength. SAF 2507® is particularly suited for use in aggressive environments such as warm chlorinated seawater and acidic, chloride containing media.
A multi-purpose super-duplex steel
Suitable for service in highly corrosive conditions and where high strength is required, the properties of SAF 2507® are being widely used in offshore oil and gas exploration and production and in heat exchangers in petrochemical and chemical processing. The grade is also suitable for hydraulic and instrumentation applications in tropical marine environments.
Main characteristics of SAF 2507®
- Very high resistance to pitting and crevice corrosion
- Excellent resistance to stress corrosion cracking (SCC) in chloride bearing environments
- High resistance to general corrosion in acids
- Excellent resistance to erosion corrosion
- Excellent resistance to corrosion fatigue
- Very high mechanical strength
- Good weldability
The below graph shows the critical pitting temperature (CPT) and critical crevice corrosion temperature (CCT) in 6% FeCl3 testing.
* PRE stands for pitting resistance equivalent and is defined as, in weight-%:
% Cr + 3.3 x % Mo + 16 x % N
The PRE value mentioned above is valid for tube and pipe.