COMPARATIVE STUDIES OF INHIBITIVE EFFECTS OF DIAMINES ON CORROSION OF ALUMINIUM ALLOY IN PRESENCE OF ACID MEDIA
Shobha Bhaskara, Sanaulla Pathapalya Fakrudeen, V. Bheema Raju, H. C. Ananda Murthy, Anjanapura V. Raghu
Abstract
The studies of inhibitive effects of 4,4-diaminostilbene (DS) and 4,4-diaminoazobenzene (DA) on the corrosion inhibition of AA2024 alloy in the presence of 1 M HCl were performed using Potentiodynamic Polarization (PDP), Electrochemical Impedance Spectroscopy (EIS) and Weight-loss methods. PDP study results indicate that DS and DA behave as cathodic inhibitors. Variation in EIS parameters indicates that DS and DA adsorb on AA2024 alloy surface resulting in the creation of some inhibitive layer. Weight-loss study indicates that inhibition efficiency of DS and DA increases with their concentration and varies with immersion time and temperature of the solution. SEM analysis of surface characteristics of samples of both inhibited and uninhibited alloys reveals that the alloy surface is smothered in the presence of an inhibitor.