Ref.: MmeCa02-002
Apresentador: Anibal Andrade Mendes Filho
Autores (Instituição): Chagas, L.S.(Universidade Federal do ABC); Antunes, R.A.(Universidade Federal do ABC); Albertin, K.F.(Universidade Federal do ABC); Mendes Filho, A.A.(Universidade Federal do ABC);
Resumo:
TiO2 nanotubes (TNTs) are oxide nanostructures grown on titanium substrates in the form of regular tubes with well-defined dimensions through specific processes. The primary method for obtaining these nanostructures is electrochemical anodization, allowing manipulation of their properties through predetermined electrochemical parameters or the substrate's phase and composition. Thus, this study aimed to investigate the effect of different alloys, such as Ti-29Nb-13Ta-4.6Zr (TNTZ), Ti-6Al-4V (Ti64), and Ti-CP2, on the growth, composition, morphology, and mechanical properties of TNTs, targeting their application in coating biomedical implants to enhance adhesion and osseointegration. The methodology involved electrochemical anodization followed by annealing, morphological characterization using SEM and TEM, mechanical characterization via scratch testing and nanoindentation, elemental, residual stress, and phase characterization using XPS and XRD. Results revealed the conversion of amorphous film to anatase upon heat treatment via XRD, while SEM and TEM analysis demonstrated a higher growth rate for TNTs formed on TNTZ, followed by Ti64 and CP2, respectively. Moreover, the internal average diameter of the films was found to be 60 nm, 53 nm, and 40 nm for TNTZ, Ti64, and CP2, attributed to a higher beta phase composition facilitating better rearrangement for oxide formation. TEM also evidenced the presence of Nb oxides incorporated into the tube structure, corroborated by XPS results confirming the existence of Nb3+ in deep film structures. Nanoindentation revealed a lower average elastic modulus for films grown on TNTZ, Ti64, and CP2, respectively, at 21 GPa, 25 GPa, and 27 GPa, attributed to higher porosity in beta phases. Additionally, scratch testing indicated greater stability and adhesion of films grown on TNTZ, with no detachment observed. These findings suggest that TNT films grown on TNTZ at 40V offer the best conditions for applications in biomedical implants.