Spectroscopic Characterization of Titanium Alloy Surface in a Biological Medium

Abstract

This work is aimed to study the effect of a biological medium simulated body fluid on surface modification of titanium alloy Ti6Al4V. Electrochemical techniques and the Raman spectroscopy are used. Polarization curves, plotted at different scan rates (5, 1, 0.5, and 0.2 mV/s), show a large range of passivation (above 3000 mV), with no occurrence of transpassivation. The return sweep shows the negative hysteresis with the shift of the corrosion potential in the more noble direction. The corrosion current is generally very low. These observations clearly confirm the high stability of the TiO2 passive film. The Raman spectroscopy shows that titanium dioxide formed consists of rutile phase. It was found that the scan rate has not a significant effect on the passivation phenomenon. However, it influences the corrosion potential and the current density. Electrochemical impedance spectroscopy allowed to establish the Nyquist diagrams and Bode around the equilibrium potential, and at different imposed potentials in the passivation field. The system behavior is not purely capacitive and so it is necessary to take in consideration the constant phase element. The impedance diagrams at different imposed potentials on the passivation field are composed only of a single loop.

A Tribological and Ion Released Research of Ti-Materials for Medical Devices

“…For Ti-6Al-4V, similar bands were observed at 152 cm −1 , 222.9 cm −1 , 798.9 cm −1 before exposure, and at 143.2 cm −1 , 233.0 cm −1 and 802.3 cm −1 after exposure. Furthermore, Nouicer et al [ 75 ] also exposed the Ti-6Al-4V to an SBF solution, observing that Raman bands were close to 150 cm −1 , 230 cm −1 , and 800 cm −1 , attributed to TiO 2 (rutile). Shaikh et al [ 76 ] studied the bioactivity and biocompatibility of Ti-6Al-4V after a surface modification by using a laser technique, which revealed Raman bands at 151 cm −1 , 217 cm −1 , 417 cm −1 , and 610 cm −1 after modification that were associated mainly with TiO 2 and Ti 3 O 5 , as oxide.…”

The tunneling radiation of a black hole with a f(R) global monopole under generalized uncertainty principle

“…The GUP as a description of the quantum gravitational influence can also be explored in the process of black hole radiation because its deviations have something to do with the tunneling probability [40,41]. The GUP [36,39,40,[54][55][56][57][58][59][60][61][62][63][64] that we employ here consists of two terms modifying the usual uncertainty and the effects of the two terms multiplied by α and β respectively are opposite each other. We find that the larger factor α causes the negative term to lower the tunnel radiation of black hole in the case of black hole with a deficit solid angle outside in the f (R) scheme.…”

“…Here we turn our discussions in the context of GUP. The Heisenberg's uncertainty principle is generalized within the microphysics regime as [36,39,40,[54][55][56][57][58][59][60][61][62][63][64],…”

The fragmentation instability of a black hole with f(R) global monopole under GUP

“…The discussion on the fragmentation of a black hole with f (R) global monopole is performed in the context of GUP. The Heisenberg's uncertainty principle can be generalized within the microphysics regime as [25,[29][30][31][35][36][37][38][39][40][41][42][43][44]…”