Zagazig University Digital Repository
Home
Thesis & Publications
All Contents
Publications
Thesis
Graduation Projects
Research Area
Research Area Reports
Search by Research Area
Universities Thesis
ACADEMIC Links
ACADEMIC RESEARCH
Zagazig University Authors
Africa Research Statistics
Google Scholar
Research Gate
Researcher ID
CrossRef
Factors affecting the anodic behaviour of zinc electrode in borate solutions
Faculty
Science
Year:
2006
Type of Publication:
Article
Pages:
343-360
Authors:
Abd El Aal, EE
DOI:
10.1016/j.corsci.2005.01.003
Journal:
CORROSION SCIENCE PERGAMON-ELSEVIER SCIENCE LTD
Volume:
48
Research Area:
Materials Science; Metallurgy \& Metallurgical Engineering
ISSN
ISI:000235462500005
Keywords :
zinc, pitting corrosion, borate, sulphur-containing anions, passivation and galvanostatic polarization
Abstract:
The anodic behaviour of Zn electrode in 1 X 10(-2) M Na2B4O7 solutions in the absence and presence of various concentrations of Na2SO4, Na2S2O3 or Na2S as aggressive agent was studied by galvanostatic polarization technique. In the absence of sulphur-containing anions in solution, the polarization curves are characterized by one distinct arrest corresponding to Zn(OH)(2) and/or ZnO, after which the potential increases linearly with time due to the formation of barrier oxide film before reaching the oxygen evolution reaction. The duration time of the arrest decreases with increasing current density while the rate of oxide film formation increases. On the other hand, the duration time of the arrest increases with the number of anodic cyclization while the rate of oxide film formation decreases. Additions of low concentration of the aggressive anions have no effect on the passive film formed on the metal surface. The potential starts to oscillate within the oxygen evolution region with increases in the concentration of these aggressive anions. Further increases in the concentration of these aggressive anions are associated with impaired Zn passivity that might indicate pitting attack. The aggressiveness of the sulphur species decreases in the order: SO42- > S2O32- > S2-. The effect of raising pH of the solution on the anodic behaviour of Zn electrode in the presence of SO42- anions was also investigated. It was found that the raising the pH of the solution affecting on the rate of oxide film formation and the breakdown potential value. (C) 2005 Elsevier Ltd. All rights reserved.
Online
PDF
جامعة المنصورة
جامعة الاسكندرية
جامعة القاهرة
جامعة سوهاج
جامعة الفيوم
جامعة بنها
جامعة دمياط
جامعة بورسعيد
جامعة حلوان
جامعة السويس
شراقوة
جامعة المنيا
جامعة دمنهور
جامعة المنوفية
جامعة أسوان
جامعة جنوب الوادى
جامعة قناة السويس
جامعة عين شمس
جامعة أسيوط
جامعة كفر الشيخ
جامعة السادات
جامعة طنطا
جامعة بنى سويف