کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1471216 990344 2009 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Corrosion behaviour of molybdate–phosphate–silicate coatings on galvanized steel
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Corrosion behaviour of molybdate–phosphate–silicate coatings on galvanized steel
چکیده انگلیسی

In this work, a Cr-free conversion layer based on molybdate–phosphate–silicate (MPS) was synthesised on a galvanized steel by simple immersion and its corrosion behaviour was compared to that of a typical chromate layer. Stationary electrochemical techniques and electrochemical impedance spectroscopy (EIS) were employed to highlight the corrosion mechanisms of both coatings in different NaCl concentrations, immersion times and pH. Contrary to the chromate layer, the MPS coating showed good electrochemical stability even in concentrated NaCl solutions and remarkable electrochemical efficiency. With increasing time, two corrosion stages were associated with the two likely sublayers of the MPS coating. Furthermore, the MPS coating behaved better than the chromate layer in acidic and alkaline pH, especially the latter as a compact corrosion product layer formed. Finally, each coating/electrolyte interface was characterised by an electrical equivalent circuit giving a satisfactory correlation between the experimental and the calculated impedance. It derived that the MPS could be an environmentally friendly alternative to chromating.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Corrosion Science - Volume 51, Issue 10, October 2009, Pages 2455–2462
نویسندگان
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