Effect of high concentration on corrosion performance of aluminium alloy inhibited by henna

Abstract

The aqueous extract of the henna leaves which their specific name is lawsonia (L), is used as a corrosion inhibitor in controlling corrosion rate of aluminium alloy (AA5083). This kind of alloy is widely used in marine application. Due to the toxicity of some corrosion inhibitors, there has been increasing research for green corrosion inhibitor. Natural inhibitor has rich sources of ingredients which have very high inhibition efficiency. However, the effectiveness of inhibition action is depending on the concentration of the inhibitor. The recent finding from other research project verifv that the inhibition efficiencies increase as the added of henna leaves concentration. The result from this present study shows the inhibition efficiency increased with the increasing of henna concentration. The highest percentage of inhibition efficiency (IE %) gained was 95.5 % at 1000 ppm henna. It can be concluded that the use of henna leaves as a corrosion inhibitor is an accepted practice in order to control the corrosion rate.