Mechanical characteristics and microstructure of drawn wire of Ti-29Nb-13Ta-4.6Zr for biomedical applications

The mechanical properties and deformation behaviors of drawn wires of Ti-29Nb-13Ta-4.6Zr with diameters of 1.0 mm and 0.3 mm (referred to as TNTZ_d1.0 wire and TNTZ_d0.3 wire, respectively) were investigated to determine the potential of this wire in biomedical and dental applications. The microstructure of forged Ti-29Nb-13Ta-4.6Zr subjected to a solution treatment at 1063 K (TNTZ_ST) comprises a single β phase with an average diameter of 25 μm, while that of the TNTZ_d1.0 wire comprises a super-fine single β phase that is elongated parallel to the drawing direction. The tensile strengths of the TNTZ_d1.0 and TNTZ_d0.3 wires are around 740 MPa and 800 MPa, respectively. While both the elongations are nearly equal (around 5.0%), the elastic modulus of the TNTZ_d1.0 wire (around 50 GPa) is slightly lower than that of the TNTZ_d0.3 wire (around 55 GPa). The notch-fatigue limit of the TNTZ_d1.0 wire is 250 MPa. The stress-strain curves of the TNTZ_d1.0 and TNTZ_d0.3 wires in the elastic deformation region have two gradients, and the maximum elastic strains are nearly equal to each other and very large (around 3.0%). In the general stress-strain curve for TNTZ_ST, the maximum elastic strain is around 1.4%.