Technology and Challenges in Additive Manufacturing of Duplex Stainless Steels

Abstract

Duplex stainless steels (DSS) comprise equivalent proportions of ferrite (alpha) and austenite (gamma) and exhibit excellent integration of mechanical and corrosion properties. The ferrite matrix provides better strength and stress corrosion resistance, whereas the austenite matrix accounts for good pitting corrosion resistance and toughness. Duplex stainless steels are widely utilized in the chemical industry, oil refineries, and machine industries. Direct energy deposition (DED) and powder bed fusion (PBF) are the two additive manufacturing techniques widely used for metals. This article covers the technologies like processing DSS by selective laser melting (SLM), variation in mechanical and microstructural properties of duplex stainless steels manufactured by additive manufacturing technique, and challenges of additive manufacturing processes.