Structure and Mechanical Properties of a Zr-1Nb Alloy, Obtained by the Method of Severe Plastic Deformation

Abstract

Effect of severe plastic deformation and subsequent annealing in the temperature range of 573–873 К on the structural and phase state of a heterophase Zr-1Nb alloy are studied by electron microscopy and X-ray diffraction analysis. Dissolving of the secondary phases particles and formation of the ultrafine-grained grain-subgrain structure with an average element size of (0.25±0.1) μm is established to occur in the process of severe plastic deformation. Precipitation of nanoscale particles of secondary phases during subsequent annealing allows to form in alloy the ultrafine-grained structure stable up to 523 К. Formation of the ultrafine-grained structure in the Zr-1Nb alloy leads to increasing its strength characteristics by 1.5–2 times and simultaneous reducing of deformation to failure by 2 times.