Effect of Acid Treatment on the Surface Modification of Ti-6Al-7Nb and Ti-5Al-2Nb-1Ta and Its Electrochemical Investigations in Simulated Body Fluid

Ti-6Al-7Nb and Ti-5Al-2Nb-1Ta specimens were subjected to two-step chemical treatments by mixture of acids (HCl + H2SO4) followed by alkali (NaOH) and heat treatment to produce a porous anatase gel layer which enhances the osseointegration. The influence of immersion time on the behaviour of the treated alloys in SBF was investigated using X-ray diffraction and scanning electron microscopy analyses and Fourier transform infrared spectroscopy analysis. Polarization study exhibited that the specimens after immersion in SBF solution showed high corrosion resistance which is attributed to the apatite growth on surface-modified Ti-6Al-7Nb and Ti-5Al-2Nb-1Ta surfaces.