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[References: 30 tit.]

Using optical, scanning- and transmission-electron microscopy, and also electron backscatter diffraction, we demonstrate that the microstructure of samples of commercially pure titanium VT1-0 and titanium alloys VT6 and VT14, obtained by the wire-feed electron-beam additive method, consists of columnar primary grains of the β phase of titanium containing crystals of packet and lamellar martensite phases. Х-ray diffraction phase analysis shows that the concentration of the residual β phase in the VT6 and VT14 samples is 2.9 and 10.5%, respectively. The concentration of alloying elements in the α and β phases of titanium alloys is measured by energy-dispersive analysis. The effect of alloying elements on the lattice parameters of the α phase of the samples is demonstrated. The different concentration of the residual β phase in titanium alloys VT6 and VT14 can be explained by considering the electronic structure of atoms of alloying elements. Tensile residual stress is present in samples VT1-0, while the residual stress in samples VT6 and VT14 is compressive. The presence of aluminum in the titanium alloys affects the sign and magnitude of the residual stress in titanium-alloy samples.