Microstructural Evolution and Anisotropy in Stainless Steel 316L from Wire Arc Additive Manufacturing

Wire arc additive manufacturingWire arc additive manufacturing (WAAM) is economical when compared against traditional methods and can save up to 50% on fabrication investment. In this study, deposits of SS316L are fabricated with wire arc additive manufacturingWire arc additive manufacturing (WAAM) with cold metalMetals transfer mode. The directional cooling along the build direction leadsLead to the epitaxial grain growth. The electron back scattered diffractionElectron back scattered diffraction (EBSD) is used to analyse the microstructureMicrostructure. The phase map indicates the presence of austenite (γ) and residual ferrite (δ) phases. The grain coarsening of the previously deposited layers takes place as the next layer is deposited, due to additional heat input and partial re-melting of previously deposited layer(s). The tensile test of samples along the build, travel, and diagonal directions reveal significant anisotropyAnisotropy. The mechanical performance along the diagonal direction is better than the other directions.