Analysis of Electrochemical Noise in Titanium Alloys Used in Aeronautics

Abstract

Corrosion is an essential factor to consider when designing and manufacturing a metallic component. In aeronautical industry is not the exception, especially because there are many types of corrosion that can affect different elements of aircrafts. Analysis is a way to determine the behavior of the material selected to decide if it's the appropriated to the purpose. This project is focused in electrochemical noise, which is a technique that measures oscillations in potential and electrochemical current of a material exposed in different solutions that represent the environment. In this case, the alloy Ti-6Al-4V composed by 90% titanium (Ti), 6% aluminum, and 4% vanadium (4V), will be studied under diverse conditions. In this research the corrosion behavior of Titanium alloys is studied by means of the electrochemical noise technique, using 2048 data per sec. The materials were evaluated in the presence of 3 different electrolytes: (water), NaCl (sodium chloride) and (sulfuric acid) at 25ºC and 3.5% of concentration. The results indicate that the behavior of the time series does not have transients of high frequency and amplitude and with the localization index the type of corrosion is generalized.