vestichИзвестия Национальной академии наук Беларуси. Серия химических наукProceedings of the National Academy of Sciences of Belarus, Chemical Series1561-83312524-2342The Republican Unitary Enterprise Publishing House "Belaruskaya Navuka"10.29235/1561-8331-2022-58-1-94-104vestich-710Research ArticleТЕХНИЧЕСКАЯ ХИМИЯ И ХИМИЧЕСКАЯ ТЕХНОЛОГИЯTECHNICAL CHEMISTRY AND CHEMICAL ENGINEERINGЗащитные свойства Zr-содержащих конверсионных покрытий на цинкеProtective properties of Zr-containing conversion coatings on zincТарасевичА. В.TarasevichA. V.

Тарасевич Александр Васильевич – аспирант

ул. Свердлова, 13а, 220006, Минск

Tarasevich Aleksandr V. – student

13a, Sverlova str., 220006, Minsk

altava98@mail.ruМатысВ. Г.MatysV. G.

Матыс Владимир Генрихович – кандидат химических наук, доцент

ул. Свердлова, 13а, 220006, Минск

Matys Vladimir G. – Ph. D. (Chemistry), Associate Professor

13a, Sverlova str., 220006, Minsk

vmatys@belstu.byПоплавскийВ. В.PoplavskiyV. V.

Поплавский Василий Владимирович – кандидат физико-математических наук, доцент

ул. Свердлова, 13а, 220006, Минск

Poplavskiy Vasiliy V. – Ph. D. (Physics), Associate Professor

13a, Sverlova str., 220006, Minsk

vpoplav@yandex.byАшуйкоВ. А.AshuikoV. A.

Ашуйко Валерий Аркадьевич – кандидат химических наук, доцент

ул. Свердлова, 13а, 220006, Минск

Ashuiko Valeriy A. – Ph. D. (Chemistry), Associate Professor

13a, Sverlova str., 220006, Minsk

ashuiko@belstu.byЖарскийИ. М.ZharskiyI. M.

Жарский Иван Михайлович – кандидат химических наук, профессор

ул. Свердлова, 13а, 220006, Минск

Zharskiy Ivan M. – Ph. D. (Chemistry), Professor

13a, Sverlova str., 220006, Minsk

tep@belstu.byБелорусский государственный технологический университетBelarusian State Technological University20221103202258194104Copyright © Тарасевич А.В., Матыс В.Г., Поплавский В.В., Ашуйко В.А., Жарский И.М., 20222022Тарасевич А.В., Матыс В.Г., Поплавский В.В., Ашуйко В.А., Жарский И.М.Tarasevich A.V., Matys V.G., Poplavskiy V.V., Ashuiko V.A., Zharskiy I.M.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://vestichem.belnauka.by/jour/article/view/710

Цель исследования − разработка экологически безопасной бесхромовой технологии пассивации гальванически оцинкованной стали. Пассивация гальванических цинковых покрытий проводилась осаждением на них конверсионных покрытий из растворов, содержащих ZrO(NO3)2, Na2SiF6 и окислитель H2O2 или K2S2O8. Изучалось влияние pH раствора, концентрации Na2SiF6 и типа окислителя на показатели защитных свойств покрытий методом капли и электрохимическим методом линейной вольтамперометрии в 3 %-ном NaCl с использованием полного факторного эксперимента 23 . Рассчитаны главные эффекты и эффекты взаимодействия исследованных факторов для времени потемнения капли и потенциала растворения цинка. Наибольшее влияние на оба показателя оказывает pH раствора в присутствии окислителя K2S2O8. Концентрация Na2SiF6 оказывает значительное влияние на потенциал растворения цинка и наименьшее влияние на время потемнения капли. Увеличение pH раствора и концентрации Na2SiF6 увеличивает показатели защитных свойств покрытий. Измерения потери массы и потенциала разомкнутой цепи в процессе ресурсных испытаний конверсионных покрытий в 3 %-ном NaCl показали возрастание скорости коррозии со временем.

The aim of the study is to develop an environmentally friendly chromium-free passivation technology for galvanized steel. Passivation of zinc coatings was carried out by deposition of conversion coatings from solutions containing ZrO(NO3)2, Na2SiF6 and oxidizer H2O2 or K2S2O8. The effect of the solution pH, the concentration of Na2SiF6 and the type of oxidizer on the protective properties of coatings was studied by the drop method and electrochemical method of linear voltammetry in 3 % NaCl using the full factor experiment 23 . The main effects and effects of the interaction of the studied factors for the darkening time of the droplet and the dissolution potential of zinc are calculated. The solution pH in the presence of the oxidizing agent K2S2O8 influences the both parameters in the most extent. Concentration of Na2SiF6 has a significant effect on the dissolution potential of zinc and the least effect on the darkening time of the droplet. An increase in the solution pH and the concentration of Na2SiF6 increases the protective properties of the coatings. Measurements of the mass loss and open circuit potential during the resource testing of conversion coatings in 3% NaCl showed an increase in the corrosion rate over time.

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The authors declare that there are no conflicts of interest present.