Effect of Cu on the passivity of Ti–xCu (x = 0, 3 and 5 wt%) alloy in phosphate-buffered saline solution within the framework of PDM-II

The effect of copper content on the passivity Ti–xCu alloys in a phosphate-buffered saline electrolyte (pH 7.4), steady-state condition, was examined using potentiostatic polarization, electrochemical impedance spectroscopy, and Mott-Schottky analysis. study demonstrates that oxide layer forms surface have n-type semiconducting character, thickness is observed linearly depends applied potential. observations are line with predictions Point Defect Model (PDM-II), which provides physiochemically realistic description formation alloys. reveal Cu additions result decrease charge transfer resistance capacitances associated hydroxide barrier layer, an increase donor density, reduce also exhibits current density after initial addition 3 wt% attributed to progressive substitution cation sublattice film resulting enhanced electrostatic interaction between immobilized copperCuTix?, mobile interstitialsCui+, carries excess over conveyed by oxygen vacancies Vo•• layer. Moreover, it hundred-year implant period, about 0.006 cm (0.06 mm) Ti–3Cu alloy predicted lose due corrosion PBS solution under given set conditions, further seen that, as amount increased from 5 alloys, rate decreases.