Estudo do comportamento eletroquímico das ligas Ti-4Si e Ti-12Si em NaCl 3,5% e Etilenoglicol 40% em NaCl 3,5%

Abstract

In the present work, the resistance to corrosion of titanium-silicon alloy was studied using electrochemical techniques such as polarization, Cyclic Voltammetry and Electrochemical Impedance Spectroscopy, complemented with surface analysis, using an optical microscope. The solutions used for electrochemical tests have been NaCl 3.5% (w / v) ethylene glycol and 40% (v / v) in 3.5% NaCl (w / v). The results showed that the studied alloys have a high corrosion resistance, low corrosion currents and high polarization resistance. Electrochemical Impedance Spectra indicated that the oxide film formed on the surface of the alloy, consists of a compact layer and a porous layer which is not formed in presence of ethylene glycol in the range of - 1.0 to 3.0 V. The micrographs taken after the polarization tests and electrochemical impedance showed no pitting or crevice attack.