Anodization and nonstructural surface characterizations of fabricated Ti–29Nb–13Ta–7.1Zr alloy for biomedical applications and its mechanical, wettability, tribological, and corrosion properties

Abstract

Implants subjected to tribocorrosion release metallic ions and solid wear debris, which can cause a peri-implant disease, bone loss, and eventually implant loosening. TiO2 coatings have a wide application range owing to their biocompatibility. In this study, the Ti–29Nb–13Ta–7.1 Zr alloy was fabricated using powder metallurgy technique. The samples were electrochemically oxidized to produce self-standing TiO2 nanotubular arrays followed by annealing for 1 h at 450 °C to improve their crystallinity. The prepared TiO2 coatings were characterized by SEM, X-ray diffraction, and EDX, and the wettability, tribomechanical characteristics, and corrosion behavior of bio-functionalized TiO2 nanotubes were investigated. Atomic force microscopy observations were conducted to examine wear scars, and the wear volume was measured via 2D profilometry. Microhardness and nanoindentation tests were performed to evaluate the mechanical characteristics of TiO2 nanotubes such as microhardness, nanohardness, and modulus of elasticity. The thickness and diameter of the observed TiO2 nanotubes are 2 μm and 90.94 nm, respectively. The obtained results revealed that the deposition of a biofunctionalized Ti/TiO2 nanotube layer enhanced the hydrophilicity, tribomechanical properties, and corrosion resistance of the Ti–29Nb–13Ta–7.1Zr alloy. The COF of Ti alloy was 0.51 and it decreased to 0.28 after anodization and annealing at 450 °C. The contact angle of the Ti sample was 79.9° and it decreased to 45.6° after annealing at 850 °C. However, after the anodic oxidation and annealing at 450 °C, the contact angle decreased to 45.6°.