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[References: p. 447 (19 tit.)]

Bioinert Zr-1Nb alloy, which is a prospective material for the fabrication of implants for different applications, is studied. Annealed billets of the alloys are subjected to severe plastic deformation including multi-cycle abc-pressing and multipass rolling in grooved rolls. The abc-pressing stage involves three cycles of pressing within the temperature range 500-400°C with one pressing in each cycle at a given temperature. In the second stage, the billets are deformed through rolling in grooved rolls at room temperature. Rolling in grooved rolls provided the formation of a homogeneous structure throughout the bulk billet volume and additional grain refinement. After annealing the alloy had a fine-grained structure consisting of 2.8 µm sized equiaxial [alpha]-Zr matrix grains and 0.4 µm sized [beta]-Nb particles distributed on the boundaries and interiors of [alpha]-Zr matrix grains. As a result of severe plastic deformation, a binary ultrafine-grained alloy with 0.2 µm size of structural elements was obtained. Transmission electron microscopy shows that the microstructure of the alloy consists of [alpha]-Zr grains, while [beta]-Nb phase grains are not identified structurally or via X-ray diffraction. Only the diffraction identification analysis reveals the presence of [beta]-Nb in the alloy. Ultrafine-grained structure enhances the mechanical properties of the alloys: yield stress 450 MPa, ultimate tensile strength 780 MPa, and microhardness 2800 MPa are obtained while keeping a low value of Young's modulus (51 MPa) comparable to the Young's modulus of bone tissue.