Textured TNZT surfaces via hydrothermal treatments for bone implant applications

Highlights: • TNZT alloys produced by vacuum arc melting of pure elements • Oxide nano-scaffolds grown on TNZT samples using a hydrothermal treatment • Nano-scaffolds were found to grow for a sodium hydroxide concentration of 5.0 M regardless of the treatment time - Abstract: TNZT alloys such as Ti-35Nb-7Zr-5Ta exhibit better biocompatibility than the more widely used Ti-6Al-4V alloy. Furthermore, TNZT alloys typically have lower Young's moduli (50–60 GPa) than most Ti-based alloys. A low modulus allows for a greater transfer of functional loads since it is much closer to the modulus of bone, which ultimately leads to more growth and support from natural bone. TNZT alloys were produced by vacuum arc melting of pure elements that were subsequently rolled to sheet. Oxide nano-scaffolds were grown on TNZT samples using a hydrothermal treatment in 40 mL sodium hydroxide solution at 60 °C using either 0.5 or 5.0 M concentrations, with and without TiO₂ nanoparticles, for either 24 or 48 h to create nanostructured surfaces to help improve osseointegration. The alloys with and without nano-scaffolds were characterized using top-view and cross-sectional scanning electron microscopy equipped with an energy dispersive x-ray spectrometer to investigate the structure, morphology, and chemistry of the resulting nanostructures. Nano-scaffolds were found to grow for a sodium hydroxide concentration of 5.0 M regardless of the treatment time (24 to 48 h). A pore size of 60 nm and 80 nm were observed for samples treated for 24 and 48 h, respectively. No porous structures were observed for samples produced for a sodium hydroxide solution of 0.5 M or with TiO₂ nanoparticles.