Structural evolution of 321 stainless steel in electron beam freeform fabrication

The study of the structural evolution in the specimens of austenitic steel 321 manufactured by an additive method through the melting of a wire material by an electron beam in a vacuum chamber has been carried out using optical metallography, scanning electron microscopy and EBSD analysis. Tensile properties were determined on standard dumbbell specimens. The studies of the structure and properties showed that the 3D-printed samples have a pronounced dendritic structure with a sharp fusion boundary between the substrate and the printed material. The mechanical properties of the specimens are at the level of those cast austenitic steel 321.