| Feature | SS316 (Austenitic) | Duplex 2205 (Austenitic-Ferritic) |
|---|---|---|
| Microstructure | 100% Austenitic | 50% Austenitic / 50% Ferritic |
| Yield Strength | ~205 MPa | ~450 MPa (Double the strength) |
| PREN (Pitting Resistance) | ~24 | ~35 (Significantly higher) |
| Stress Corrosion Cracking (SCC) | Susceptible in warm chloride environments | Highly resistant |
| Primary Applications | General Marine, Chemical, Pharma | Offshore Oil Rigs, Desalination Plants, Subsea |
The Verdict
Duplex 2205 is the clear winner for highly stressed components in aggressive chloride environments. Its doubled yield strength allows engineers to design smaller, lighter fasteners without sacrificing safety.
Frequently Asked Questions
Is Duplex magnetic?
Yes, unlike fully austenitic SS316, Duplex contains a ferritic phase which makes it magnetic.