الفهرس 
Chapter One: IntroductionOnly 14 pages are availabe for public view
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Abstract
Corrosion is one of the most important problems that metals are
exposed to, which negatively affects various industries caused by the
electrochemical interaction with the corrosion environment. This thesis
discusses the corrosion of C-steel in an acidic medium and works to
protect it by reducing its risks - as it is not possible eliminate corrosion
completely-Using some organic compounds .
The thesis included three main chapters:
The first chapter
Deals with introduction which included a historical introduction to
the phenomenon of corrosion, the basics of the science of corrosion of
metals, their forms, types, and methods of protection from them. The
published research papers on the corrosion of the C-steel metal in acid
solutions and the ability of organic inhibitors were also included the
target of the thesis.
The second chapter
Includes the chemical composition of the C-steel used in the study
and also ways to prepare solutions of acid (hydrochloric acid) and
review of the name, chemical composition, molecular weight and molecular formula of organic compounds and description the chemical
and electrochemical methods that were used to measure the rate of
corrosion of measurement, as well as the preparation of the electrodes,
the cell and solutions and methods of calculations.
The third chapter
Deals with the results obtained and their discussion and is
divided into three sections:
Section І:
Contains the practical results of the weight loss method which
and their discussion . The results were presented in tables and curves.
The organic compounds used in the study reduce the corrosion of C-steel
The efficiency of inhibition has been studied in the range of different
concentrations of the two organic compounds.
This method was used to find out the effect of temperature on the C-steel
in hydrochloric acid solution at four different temperatures (30-45°C),
and it was found that the rate of corrosion increases with increasing
temperature, and hence decreasing inhibition efficiency, which shows
that inhibition occurs through physical adsorption of inhibitors and
follows the Langmuir isotherm and Temkin isotherm.
The negative values of (ΔG˚) indicate that the adsorption process on the
surface of C-steel is carried out spontaneously and the activation parameters for the compounds have been studied. The thermodynamic
functions related to the activation process were also calculated with a
discussion of the implications of their values.
Section ІІ:
Potentiodynamic polarization measurements were carried out
for C- steel in hydrochloric acid solution .It was found that there is a
displacement of the cathodic and anodic polarization curves to more
-ve and more +ve values, It was found that the corrosion rate decreases
with the increasing in the concentration of the inhibitor, thus increasing
the efficiency of the inhibition process. These inhibitors act as mixed
type inhibitors.
Section ІІІ:
AC impedance spectroscopy measurements were carried out for
C-steel in hydrochloric acid in the absence and presence of inhibitors and
is controlled by the charge transfer resistance(Rct) and revealed that the
values of the transfer resistance increase by increasing the concentration
of inhibitor. On The other hand (Cdl) decreased by increasing
concentration of inhibitors .
The thesis is written on (73) pages and contains (17) tables in
which the results are written and (25) figures showing the results.