Review of Fabrication Methods Employed for 3D Printing DSS Parts using GMAW-AM Process: A Systematic Analysis

Research studies on the Duplex Stainless Steel (DSS) parts fabricated by the Gas Metal Arc Welding-Additive Manufacturing (GMAW-AM) process have revealed that undesired deposition geometry, ferrite-austenite (α-γ) phase imbalance, sigma (σ) phase formation, and anisotropic properties are a usual predicament, given the complex nature of the GMAW-AM process and highly sensitive alloy composition of the DSS. To what extent these problems have been resolved is a pertinent question. This study systematically reviewed the research published in the last ten years involving different GMAW-AM methods for DSS parts fabrication. Particularly, the translated effects of process parameter optimisation, shielding gas combination, and special material and mechanism assisted methods on the geometrical, microstructural and performance characteristics of parts were critically analysed. The results showed that the research intervention for enhancing metallographic and mechanical attributes of GMAW-AM-based DSS parts has a high merit for obtaining tailored grain growth, crystal formation, and balanced α-γ phases with minimal σ phases. A suitable fabrication route, backed by available literature, is presented to provide future research directions.