Ehteram A. Noor  , 
    Comparative Study on the Corrosion Inhibition of Mild Steel by Aqueous Extract of Fenugreek Seeds and Leaves in Acidic Solutions,
    Journal of Engineering and Applied Sciences,
    Volume 3,Issue 1,
    2008,
    Pages 23-30,
    ISSN 1816-949x,
    jeasci.2008.23.30,
    (https://makhillpublications.co/view-article.php?doi=jeasci.2008.23.30)
    Abstract: Electrochemical impedance spectroscopy and potentiodynamic polarization measurements were used to study the effect of Aqueous Extract of Fenugreek Leaves (AEFL) and Aqueous Extract of Fenugreek Seeds (AEFS) on the corrosion of mild steel sin HCl and H<SUB>2</SUB>SO<SUB>4</SUB> solutions. In both acids, AEFL and AEFS act predominately as anodic type inhibitors. The inhibition efficiency of both AEFL and AEFS increases with increasing of their concentration in 2.0 M of both acids, but at certain concentration of both extracts it decreases with increasing concentration of both acids. However, in HCl solutions, the inhibition efficiency of both AEFL and AEFS was always greater than in H<SUB>2</SUB>SO<SUB>4</SUB> solutions for otherwise identical conditions. In HCl solutions the adsorption of both AEFL and AEFS on mild steel surface obeys the Langmuir adsorption isotherm, while obeys the Temkin adsorption isotherm in H<SUB>2</SUB>SO<SUB>4</SUB> solutions. It was found that the obtained results from EIS and PDP measurements are in good agreement. Good correlation between the inhibitor constituents and its inhibition efficiency in both acids was obtained and discussed.
    Keywords: Corrosion inhibition;aqueous extract;acidic solutions;AEFL;AEFS