Corrosion inhibition of 6061 aluminium alloy/SiCp composite in hydrochloric acid medium using 3-chloro-1-benzothiophene-2-carbohydrazide

Abstract

The inhibitive action of 3-chloro-1-benzothiophene-2-carbohydrazide (CBTC) on the corrosion behavior of 6061 Al alloy/SiCp composite has been studied at four different temperatures (30°, 40°, 50° and 60°C) in hydrochloric acid medium (0.5 and 1 M) using Tafel extrapolation technique and weight loss method. Polarization curves indicate that CBTC acts as cathodic inhibitor. Inhibition efficiency is found to increase with increasing inhibitor concentration upto a critical value and with decreasing temperature. The inhibition efficiencies obtained by Tafel extrapolation technique and weight loss method are in good agreement. The adsorption of the inhibitor on the composite surface is found to obey Temkins' and Langmuir adsorption isotherms. The inhibition is governed by physisorption mechanism.