Evolution of Deformation Texture in Low Modulus β Ti-34Nb-2Ta-(0, 3)Zr-0.5O Alloys

Ti-Nb-based low modulus metastable β-titanium alloys are popular choice for orthopedic implant materials. The performance of these materials could be affected by variation in crystallographic texture developed during processing. In the present study, texture evolution during unidirectional rolling and multi-step cross-rolling of the alloys Ti-34Nb-2Ta-3Zr-0.5O (TNTZO) and Ti-34Nb-2Ta-0.5O (TNTO) (in wt pct) has been studied. In both the alloys, the rolling texture is characterized by the absence of RD∥〈110〉 fiber, and cross-rolling leads to a stronger texture than unidirectional rolling. However, the prominent texture components in the cross-rolled condition are different for the two alloys. The TNTZO alloy shows the formation of a strong γ-fiber (ND∥〈111〉) along with {001}〈110〉 components while in TNTO, the texture is dominated by strong {001}〈110〉 component. These experimental results have been analyzed by simulations using viscoplastic self-consistent model and further validated by microstructural analysis using electron back scattered diffraction (EBSD). The deformation texture evolution has been attributed to a predominantly \( \left\{ {11\overline{2} } \right\}\left\langle {111} \right\rangle \) slip. The simulated texture of Ti-34Nb-2Ta-0.5O alloy shows a minor deviation from the experimental texture, which can be related to the reduced stability of this alloy due to the absence of Zr.