Duplex Stainless Steel is a family of stainless steels whose microstructure at room temperature consists primarily of a mixture of austenite and ferrite.
Reference Definition by Bssa.org.uk: Duplex Stainless Steel is to produce a chemical composition that leads to an approximately equal mixture of ferrite and austenite. This balance of phases provides the following: Higher strength (The range of 0.2% PS for the current duplex grades is from 400 – 550 MPa); Good weldability in thick sections; Good toughness; Resistance to stress corrosion cracking. (Refer to an Austenitic: low strength (200 MPa 0.2% PS in solution annealed condition), low resistance to stress corrosion cracking, and Ferritic: low strength (a bit higher than austenitic, 250 MPa 0.2% PS), poor weldability in thick sections, poor low temperature toughness)
Related Definitions in the Project: The Metallurgy (Corrosion and Cracking)
