A comparative study of leaves extracts for corrosion inhibition effect on aluminium alloy in alkaline medium

Abstract

This paper deals with the comparative inhibition study of some plants leaves extract namely Cannabis sativa (CS), Rauwolfia serpentina (RS), Cymbopogon citratus (CC), Annona squamosa (AS) and Adhatoda vasica (AV) on the corrosion of aluminium alloy (AA) in 1 M NaOH. The corrosion tests were performance by using gravimetric, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and linear polarization resistance (LPR) techniques. RS showed maximum inhibition efficiency (η%), 97% at 0.2 g L−1. Potentiodynamic polarization curves justified that all the inhibitors are mixed-type. Surface morphology of AA is carried by scanning electron microscopy (SEM) and atomic force microscopy (AFM)