Structural and Phase State of Ti–Nb Alloy at Selective Laser Melting of the Composite Powder

Phase composition and microstructure of Ti–Nb alloy produced from the composite titanium and niobium powder by selective laser melting (SLM) method were studied in the present research. Ti-Nb alloy produced by SLM is a monolayer and has zones of fine-grained and medium-grained structure with homogenous elemental composition within the range of 36–38 wt.% Nb. Phase state of the alloy corresponds to the main phase of β- solid solution (grain size of 5–7 μm) and non-equilibrium martensite α″-phase (grain size of 0.1–0.7 μm). Grains of the α″-phase are localized along the boundaries of β-phase grains and have a reduced content of niobium. Microhardness of the alloy varies within the range of 4200–5500 MPa.