الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
1. A literature survey of the different theories of
oorrosion and passivity of copper in different
media (aoidio, alkaline and ~eutral) i8 given
with particular emphasis on the effect of aggressive
ions as well as the use of organic inhibitors.
2. The potential of the oopper electrode was followed
in oxygenated solutions of the sodium salts of
carbonate, bicarbonate, Inonohydrogf!nphosphate,
chromate, borate, tungestate,_ chloride, bromide wid
sulphate, respectively, of varying concentrations.
). The steady-state potential, Bst.’ varies with
concentration of the anions (mentioned in 2) aocording
to
4. When the BtSgressive iona cr” and nr- were added to
the carbonate, chromate and borate u~)lutiolls, in
which copper electrode was previously eqUe~ibrated,
sigmoidal s-a~d curves were obtained. The~ints
of inflexion of these curveD occur at larger addition
of the aggressive ions, the higher-ot-’the concentrat- ion of the inhibitive anf.one in solution. The two
parameters are related as:
Log Cinh•• KJ + nJ log Cagg.
For the exponent ”n)” it Waf’ found thats
i- Its value depends primarily on the type of the
inhibitor and is higher in borate solutions
than in oarbonate and chromate.
ii- Its value for 01- is greater than that for Brin
the borate solutions.
5. The dissolution of oopper in rulO) was determined by
measuring the temperature rise usinG J.lyliuSthermometric
technique. The rate of dissolution was found
to inorease on inoreasing the aoid conoentration
according to an autocatalytic mechanism involvinG •
the formation of lliIc:O”.
6. Addition of monomethyl-. dimethyl-. trimethyl-. monoethyl-.
diethyl-. triethyl-amines and hydra.zine
decreases the dissolution rate of Ou in 6 11 IrNO) by
adsorption on the metal surface and/or by altering
the autocatalytic dissolution reactions. On the
other hand, 01-, lIO; and:l)’4 iOilS alter the rate
of dissolution through the interference wLth oathodio
areas. These ions are assumed to compete with some
oathodio depolarizing compommts for adsorption si tea
on the metal surfaoe.
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7. Cyolio yolt8””””g%’8o1u1rves were construoteli in
Na
2
CO
J
solutions as a tunotion of the final enodio
potential. eleotrolyte ooncentration end soanning
rate.
8. The effeot of addition of increasing conoentrations
of Cl ions on the cyclio voltBlllJl1etryof au was ----- studied in Na
200J solutions of different oonoentrations.
It was found that the integrated charges
under the cyclic voltommogramsincreases mark@dly
with increasing the 01- ion concentrations, due to
the propagation of pitting corrosion. The differenoe
of the oharges amounts.b.qat in the presence ~=--
and absenoe of 01- ions is taken as a measure of the
extent of pitting corrosion to take place-.,6. Cia-- varies with the 01- ion conoentration according tOI
9. from the potentiodynamic polarization measurements.
it waS found that. the critical potential for pitting
to take place varies with the 01- ion ooncentration
aocording to a sigmoidal 5-shaped ourves
10. Addition of inorganic inhibitive anions. e.g •• Cr0’4’
W0’4’ KP0’4 and B40’7 shift the critical pitting
potential into the noble direction indicating
inoreased resistance to pitting corrosion.
11. SUfficient conoentrations of the inhibitive anions
oause complete pitting inhibition. The conoentration
of the inhibitive inorganio anions that can
wi thstand the corroding action of a oertain
concentration of Cl- ion can be deduoed from
equationa
Log einh • ••
where K
4
and n4 are oonstants.