Study of corrosion behavior of Ti6AI4V alloy and stability of TiO_2 films thermally obtained and doped with lanthanum salt

摘要

The present work is an electrochemical study of Ti6AI4V alloy and TiO_2 films obtained by the technique of thermal oxidation, and the use of lanthanum salt as a corrosion inhibitor. The electrochemical characterization was performed in Hank's synthetic physiological solution (SH), using polarization curve techniques and electrochemical impedance spectroscopy. Additionally, in order to determine the phases present in the samples, they were characterized by techniques as scanning electron microscopy (SEM) and microanalysis and X-ray spectroscopy (DRX) in Energy Dispersive (EDS). The protective capacity against corrosion of the alloys treated (heat and lanthanum chemical conversion treatment (LaCCTs)) depends on the oxide layer thickness that was formed on the surface. The corrosion protection was performed in untreated samples thermally oxidized at 700 and 800°C for one hour and cooled for 24 hours in the oven, as well as samples heat-treated and submitted to chemical conversion treatment with lanthanum 0.01 M, which can be classified as follows: alloy Ti6AI4V