Composition and Corrosion Behavior of Iron-Cobalt-Tungsten
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Дата
2018
ORCID
DOI
doi.org/10.18321/ectj697
Науковий ступінь
Рівень дисертації
Шифр та назва спеціальності
Рада захисту
Установа захисту
Науковий керівник
Члени комітету
Видавець
Institute of Combustion Problems, Kazakhstan
Анотація
Principles of three component Iron-Cobalt-Tungsten alloys electrodeposition from complex Fe (III) based citrate electrolytes are discussed. It is shown, that deposition of ternary alloys proceeds through competitive reduction of cobalt and tungsten with iron. With increasing ligand concentration coatings are enriched with a refractory component; however, increasing current density favors a reverse trend. The effect of both current density and pulse on/off time on the quality, content of alloying metals and surface topography of electrolytic coatings were determined. The application of pulsed electrolysis provides increasing tungsten content up to 13 at.%, at current efficiency of 70–75%. Globular relief of Fe-Co-W coatings is caused by refractory metals incorporation, and crystalline and amorphous parts of structure are visualized by X-ray spectroscopy, including inter-metallic phases Co₇W₆, Fe₇W₆ along with α-Fe and Fe₃C. The crystallite size of the amorphous part is near 7–8 nm. Corrosion resistance of the coatings is 1.3–2.0 orders of magnitude higher than the substrate parameters as follows from data of polarization resistance method and electrode impedance spectroscopy.
Опис
Ключові слова
Бібліографічний опис
Composition and Corrosion Behavior of Iron-Cobalt-Tungsten / M. Ved [et al.] // Eurasian Chemico-Technological Journal. – 2018. – Vol. 20, No 2. – P. 145-152.