Duplex Stainless Steel
A family of stainless steels with a two-phase microstructure of roughly equal proportions of ferrite and austenite, offering superior corrosion resistance and strength compared to standard austenitic grades.
What is Duplex Stainless Steel?
Duplex stainless steel combines the best properties of both austenitic and ferritic stainless steels. The balanced microstructure (approximately 50% ferrite and 50% austenite) delivers roughly twice the yield strength of standard austenitic grades like 316L, with excellent resistance to stress corrosion cracking, pitting, and crevice corrosion.
Common Grades
- UNS S31803 / S32205 (2205) — The most widely used duplex grade
- UNS S32750 (2507) — Super duplex with PREN > 40
- UNS S32760 — Super duplex with enhanced corrosion resistance
Applications
Oil & gas production tubing, chemical processing, desalination plants, marine structures, pulp & paper industry, and structural applications where high strength and corrosion resistance are required.