State-of-the-art of the new alloys in the duplex stainless steel family. Alloy design, manufacturing, post treatments and applications

Abstract

Duplex stainless steels have been a big revolution mainly in the offshore oil industries. These alloys have become a very good alternative for dealing very efficiently with stress corrosion cracking (SCC) with a much lower associated cost than nickel base alloys. From their discovery in the late 1920's to the present day, these alloys have been evolving in the form of new duplex alloys which have offered increasingly better corrosion resistance and improved mechanical properties. This paper offers a brief journey through time from the beginning of the Iron Age to the present day, narrating the evolution of the use of iron in the different stages of humanity. Subsequently, all the theoretical principles associated with duplex stainless steels are described, as well as the associated technologies for obtaining and processing them. Finally, the state-of-the-art of the most recent duplex alloys, the super duplex and hyper duplex stainless steels, has been elaborated