Corrosion Control of Aluminium Alloys Using Teak Tree Leaf Extract

Corrosion inhibition of aluminium alloy by teak tree leaf extract was studied to investigate the effect on corrosion using Gravimetric experiment in 0.5M HCl. The teak tree leaves were obtained from nearby locality, washed and dried, after which they were ground to micro size. Reflux method was use to obtain 25g of leaf extract. Aluminium alloy coupons were dipped into the solutions and were removed at two hours interval. The concentration of the leaf extract was studied using weight loss measurement and the result showed that teak tree leaf extract is good inhibitor. The gravimetric measurement results showed that teak tree leaf extract increased corrosion rate at the beginning of the control experiment and subsequently corrosion rate reduced uniformly over 8 hours of exposure time. These findings showed that the inhibitor has the capacity to protect the metal surface by forming passive film. The inhibition efficiencies obtained varies from 75.33% after 8 hours of exposure to 99.80% after 2 hours of exposure of immersion, both at the 0.4 concentration of the inhibitor in the corrosive media.