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

摘要

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 beta- solid solution (grain size of 5-7 mu m) and non-equilibrium martensite alpha aEuro(3)-phase (grain size of 0.1-0.7 mu m). Grains of the alpha aEuro(3)-phase are localized along the boundaries of beta-phase grains and have a reduced content of niobium. Microhardness of the alloy varies within the range of 4200-5500 MPa.