Development and investigation of the structure and physical and mechanical properties of low-modulus Ti-Zr-Nb alloys

The criteria for the optimization of chemical composition of Ti-Zr-Nb alloys have been selected that allow for obtaining materials with low elastic moduli and which have been used to melt alloys 50Ti-(50 - x) Zr-xNb, at 15 < x < 20 at %. Transmission electron microscopy and X-ray diffraction analysis have been used to study the phase composition of the as-cast alloys and alloys after homogenizing annealing. The minimum elastic modulus (69 GPa) and minimum microhardness (2440 MPa) have been found in the almost single-beta-phase alloy with a maximum niobium content (17.1 at %). An increase in the volume fraction of alpha aEuro(3) phase in the alloys with a lower niobium content (to 15 at %) promotes the growth of values of these properties. The phase transformations that occur during the continuous heating of homogenized alloys have been studied. The dependence of the temperature of the polymorphic (alpha + beta)-beta transformation on the ratio of the alloying elements in the studied alloys have been shown.