الفهرس 
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Abstract
The thesis consists of three chapters. Chapter I is the introduction, Chapter II represents the experimental techniques and Chapter III contains the experimental results and discussion of the obtained data.
Chapter I: In this chapter an introduction is given which deals with the following fields of interest:
Electrochemical reactions, the potential of zero charge (PZC), corrosion of metals, surfactants, critical micelle concentration (CMC), surfactants as corrosion inhibitors, adsorption of surfactants, adsorption isotherms. Literature survey on inhibition of the corrosion of mild steel and aluminum by surfactants. The aim of the work was also given in this part.
Chapter II: The main contents of this chapter are the description of the experimental techniques used in the present investigation: Electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and weight loss techniques. Also the detailed description of electrochemical cell, the electrodes (working, reference and auxiliary), the preparation of the tested solutions and chemical formula of the used surfactants.
Chapter III: In this chapter the experimental results are discussed in two parts:
Part I: Deals with the effect of cetrimide and sodium lauryl sulphate (SLS) surfactants on the electrochemical behavior of aluminum in 0.1M HCl at 30 ◦C using electrochemical impedance spectroscopy, potentiodynamic polarization and weight loss techniques.
The potentiodynamic polarization curves for aluminum in 0.1M HCl solution in presence and absence of 0.005 M Cetrimide or SLS surfactants show that the addition of the surfactants to the medium leads to an increase of the current density of aluminum in the case of Cetrimide and a decrease in the current density in the case of SLS, which means that Cetrimide acts as accelerator and SLS acts as inhibitor for the corrosion of aluminum in 0.1 M HCl.
The Nyquist plots for aluminum in 0.1 M HCl in absence and presence of 0.005 M Cetrimide or SLS surfactants consist of capacitive semicircle indicating that the dissolution of aluminum is mainly controlled by charge transfer process across the metal/solution interface, the presence
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of (Cetrimide) decreased the value of the charge transfer resistance Rct. However, SLS increased its value.
Weight loss measurements for dissolution of aluminum in 0.1 M HCl in presence of different concentrations of SLS after 2 hours of immersion at 30 ◦C showed that the percentage inhibition efficiency increases with increasing concentration of SLS until leveling off indicating that the inhibition process is mainly controlled by adsorption of the surfactant at the aluminum surface until it reaches a point of saturation of the metal surface by the surfactant.