Has a mixed microstructure of austenite and ferrite, the aim being to produce a 50/50 mix, although in commercial alloys, the mix may be 40/60 respectively. Has improved strength over austenitic stainless steels and also improved resistance to localized corrosion, particularly pitting, crevice corrosion and stress corrosion cracking. Characterized by high chromium (19-28 percent) and molybdenum (up to 5 percent) and lower nickel contents than austenitic stainless steels. The most used duplex stainless steels are the 2205 (22 percent chromium, 5 percent nickel) and 2507 (25 percent chromium, 7 percent nickel). The 2507 is also called “super duplex” due to the higher corrosion resistance.
© 2020 Dixie-Southern. All Rights Reserved.