الفهرس 
Copper and its alloysOnly 14 pages are availabe for public view
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Abstract
The copper electrode potentials measured by the open circuit potential method in
strongly aerated solution of SO4-2, Cl-, Br-, I-, CrO4
-2, CO3
-2, and NO2
-, with
difference concentrations, till steady state values are attained. The copper electrode
potentials of all the experiments increase from negative to more positive values
indicating oxide film growth. The copper oxide film thickness maximum value at
low and high concentrations of each aggressive and inhibitive anions respectively.
The rate of oxide film thickening is determined by use the relation: E = a + b log t,
where a and b are constants. The concentration of the inhibitive anions, CrO4
-2,
CO3
-2, and NO2
- that can withstand a certain concentration if the aggressive ions
SO4-2, Cl-, Br-, and I-, varies due to the relation: log Cinh. = A + n log Cagg. where
A and n are constants. The corrosion behavior of copper in 2M HNO3 solution in
the absence and presence of some organic inhibitors such as phenylhydrazine,
Urea, Thiourea, N-allylthiourea, thiosemicarbazide is investigated using
gasometry, weight loss, and galvanostatic polarization technique (Tafel
measurements). Another inorganic inhibitors such as Na2WO4, Na2HPO4, and
Na2CrO4 used to study the behavior of copper corrosion in 2MHNO3 by using
gasometry measurements. The effect of temperature on the copper corrosion
inhibition has been studied by gasometry technique only. The inhibitive action of
these compounds is discussed in terms of blocking the electrode surface by
adsorption of the inhibitor molecules according to Langmuir isotherm. The
thermodynamic parameters; Ea, K ads., ΔH, ΔS, and ΔGo
ads. of the organic inhibitors
for Cu in 2MHNO3 solution were calculated by gasometry measurement. The
thermodynamic parameter ΔGo
ads. reveals strong physisorption of the inhibitors
on the copper surface. The corrosion parameters of copper [ Ecorr. (V), Icorr.(A /cm2)
, α (V)] in presences of different concentrations of HNO3 and in 2MHNO3
contains different organic inhibitors with different concentrations are.