The present work is a study of the applicability of linear polarisation resistance technique as a means for corrosion monitoring. Parameters tested were alloy composition, surface finish of specimens before exposure, concentration of aqueous environment and the additional effect of soil to the aqueou􀀂 medium. A simple galvanostatic polarisation circuit was utilized. A polarisation resistance curve was then plotted from which the corrosion current densities and corrosion rates were calculated. The results of this work show that Corrosion reactions depend on both thermodynamic and kinetic parameters, also these reactions are under mixed control and the potential actually measured at the metal surface is a mixed potential. Linear polarisation resistance technique is not a suitable corrosion monitoring technique for type 304 stainless steel. For low alloy steel, the corrosion rate increases with increase of chloride concentration of the aqueous environment to reach a maximum at seawater concentration beyond which the corrosion rate starts to decrease. Presence of soil in addition to the seawater environment causes additional resistance thus explain­ing prevailing of the type resistance overvoltage. The nature of soil affects the extent of corrosion. In the case of soil completely covered with seawater localized crevice corrosion was recognized, that is in contrast to the case where sand is moistened with few drops of seawater, the corrosion rate was very low. Condition of the metal surface before exposure affected the corrosion behaviour. Accelerating rates of corrosion are attributed to surface roughening of the metal.


School of Sciences and Engineering

Date of Award


Online Submission Date


First Advisor

M. Farag

Committee Member 1

Saad El Raghy

Committee Member 2


Committee Member 3

H. Omar

Document Type



103, [1] leaves

Library of Congress Subject Heading 1

Corrosion and anti-corrosives

Library of Congress Subject Heading 2



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Call Number

Thesis 1987/712