Кафедра "Електрорухомий склад залізниць"

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http://crust.ust.edu.ua/handle/123456789/653
ENG: The department of Electro of Railways

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Browsing Кафедра "Електрорухомий склад залізниць" by Author "Baskevich, Alexander S."

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    Electrodeposition of Nanocrystalline Chromium–Carbon Alloys from Electrolyte Based on Trivalent Chromium Sulfate Using Pulsed Current
    (Springer, 2012) Protsenko, Vyacheslav S.; Danilov, Fedor I.; Gordiienko, Victor O.; Baskevich, Alexander S.; Artemchuk, Viktor V.
    EN: The effect of pulse parameters on the electrolysis current output, nanocrystals size, composition, hardness, friction coefficient and wear resistance of nanocrystalline coatings Cr-C, obtained from the sulfuric acid-based electrolyte salts Cr (III), comprising urea and formic acid. It is shown that coatings containing ~ 9% (wt.) carbon; current density and duty cycle do not affect the composition blocked. It was found that depending on the current output from the duty cycle when there is a maximum duty cycle ~ 1.05 ... 1.1, where the output current significantly exceeds the value realized in current-mode steady-state. It is shown that if the micro-hardness Cr-C deposits obtained at DC, is close to 850-900 HV, then using a pulsed electrolysis in certain modes may increase the microhardness up to ~ 1200-1300 HV. Found that the use of pulsed electrolysis can significantly reduce the coefficient of friction chrome-carbon cover (with steel counterbody) in conditions of dry friction and under boundary lubrication, and also increases the durability of precipitation.
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    Improving Hardness and Tribological Characteristics of Nanocrystalline Cr-C Films Obtained from Cr(III) Plating Bath Using Pulsed Electrodeposition
    (Elsevier Science Publishing Company, Inc., 2012) Protsenko, Vyacheslav S.; Danilov, Fedor I.; Gordiienko, Victor O.; Baskevich, Alexander S.; Artemchuk, Viktor V.
    EN: Effect of pulsed electrodepostion on the nanocrystal size, composition, hardness, coefficient of friction and wear resistance was investigated for the Cr–C electrodeposits obtained from a trivalent chromium bath. The electrodeposits were shown to contain about 9% of carbon. Pulsed electrodeposition does not virtually affect the carbon content. At the same time, an increase in the off time duration leads to a decrease in the nanocrystals size. The hardness and wear parameters of the electrodeposits may be sufficiently improved when using pulsed current. For instance, at ton=toff=1 s, the hardness reaches the values of ~1200÷1300 HV (meanwhile, it is close to 850÷950 HV at a steady-state electrolysis).