Duplex is a family of stainless steel grades that contain a mix of austenitic (γ) and ferritic (α) phases. While the ferritic phase provides the strengthening, the austenitic lattice enables ductility and toughness.
It’s this two-phase structure that gives duplex stainless steels an elevated yield strength. In fact, duplex stainless steels are nearly twice as strong as austenitic grades. This mixed structure also means duplex have good resistance to both stress corrosion cracking and intergranular corrosion, all while maintaining a sufficient level of ductility. Furthermore, duplex’s low nickel content and high strength enable the use of thinner sections, bringing significant cost benefits to the end user.
