Ponente
Descripción
Ti6Al4V is the most common titanium alloy used in biomedical applications; however, low-modulus and non-toxic -titanium alloys have been developed in order to reduce stress shielding and avoid the release of toxic ions such as Al and V. In order to enhance the bioactivity and osseointegration, surface modifications of the implant are usually applied. Thus, the aim of this work was the study of different acid etchants on the microstructure topography and roughness of Ti6Al4V and Ti13Nb13Zr alloys.
Ti6Al4V alloy was etched using a mixture of 4HF/24HNO3 while Ti13Nb13Zr samples were soaking in Kroll’s solution for 10 and 20 secs. Also, a 20% HF solution was employed for both alloys at different immersion times. Phase composition was study using X-ray diffraction, while morphological characterization was determined by Scanning Electron Microscopy and surface roughness of the samples was obtained by 3D-optical profilometry.
For Ti6Al4V alloy, the use of 4HF/24HNO3 does not represent a significant increase in roughness; nevertheless, the values obtained at 60 secs in HF (0.27 ± 0.01 µm) are similar to those obtained at 20 secs in Kroll’s solution for Ti13Nb13Zr (0.29 ± 0.02 µm) and some changes in microstructure can be seen. For Ti13Nb13Zr, the roughness increases in Kroll’s solution up to 0.29 ± 0.02 µm and a characteristic microstructure is perceived in which the α-phase is embedded in the dark grains of the β-phase. When using HF, a strong oxidation is visible and some peaks due to partial transformation of the α-Ti phase are observed.
