vsgiuВестник Сибирского государственного индустриального университетаBulletin of the Siberian State Industrial University2304 - 44972307-1710Федеральное государственное бюджетное образовательное учреждение высшего образования "Сибирский государственный индустриальный университет"10.57070/2304-4497-2024-4(50)-120-128vsgiu-35Research ArticleРаздел 2. Металлургия и материаловедениеSection 2. Metallurgy and Materials ScienceИССЛЕДОВАНИЕ СТРУКТУРЫ ПОВЕРХНОСТНЫХ ДЕФЕКТОВ ЦИНКОВОГО ПОКРЫТИЯ, ОБРАЗУЮЩИХСЯ В РАСПЛАВЕ ТЕХНИГАЛЬВАSTUDY OF THE STRUCTURE OF ZINC COATING SURFACE DEFECTS FORMED IN THE TECHNIGALVA MELThttps://orcid.org/0000-0002-4273-2483БондареваОльга СергеевнаBondarevaOlga S.

к.т.н., доцент кафедры технологии металлов и авиационного материаловедения

Cand. Sci. (Eng.), Associate Professor of the Department of Metal Technology and Aviation Materials Science

osbond@yandex.ruСамарский национальный исследовательский университет имени С.П. КоролеваРоссияSamara National Research UniversityRussian Federation20240202202604120128Copyright © Бондарева О.С., 20262026Бондарева О.С.Bondareva O.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://vestnik.sibsiu.ru/jour/article/view/35

При горячем цинковании так называемых «реактивных» сталей, содержащих около 0,1 % (по массе) кремния, наблюдается образование цинкового покрытия разной толщины и оттенка. Для контроля толщины цинкового покрытия на сталях широко используется технология Технигальва, представляющая собой микролегирование расплава цинка никелем в количестве 0,05 % (по массе). Несмотря на популярность рассматриваемой технологии, в некоторых случаях на поверхности покрытия образуются дефекты в виде налипших «крупинок». Целью настоящей работы было исследование структуры и фазового состава дефектов покрытия, образующихся в расплаве цинка с микродобавками никеля, а также анализ причин возникновения и поиск способов предотвращения их образования. Микроструктуру покрытия в области дефектов исследовали с помощью сканирующей электронной микроскопии. Показано, что качественное покрытие состоит из стандартных интерметаллических Г-, δ- и ζ-фаз, покрытых твердым раствором цинка η-фазой. В области дефекта в η-фазе наблюдаются включения правильной геометрической формы, расположение и размеры которых говорят о том, что они налипают на покрытие в момент извлечения изделия из расплава. Идентификацию фазового состава включений проводили с помощью EDS (energy-dispersive X-ray spectroscopy) и EBSD (Electron backscatter diffraction) анализов. Установлено, что включения представляют собой ζ-фазу (изоморфную FeZn13), содержащую около 0,8 % (по массе) никеля. Показано, что основными причинами образования дефекта «крупинки» является появление в расплаве плавающих частиц отхода-дросса, вызванных загрязнением расплава цинка железом, а также локальное превышение рекомендуемой концентрации никеля. Предложены способы предотвращения дефектов рассматриваемого вида при горячем цинковании.

During hot-dip galvanizing of so-called "reactive" steels containing about 0.1 % (by weight) of silicon, the formation of a zinc coating is observed. To control the thickness of the zinc coating on steels, the Technigalva technology is widely used, which is the microalloying of the zinc melt with nickel in an amount of 0.05 % (by weight). Despite the popularity of the technology in question, in some cases defects form on the surface of the coating in the form of a stuck "grain". The purpose of this work was to study the structure and phase composition of zinc coating defects formed in a zinc melt with nickel microadditives, as well as to analyze the causes of their 

occurrence and find ways to prevent their formation. The microstructure of the coating in the area of defects was studied using a scanning electron microscopy. It is shown that the high-quality coating consists of standard intermetallic G-, δ- and ζ-phases, coated with a solid zinc solution with the n-phase. In the area of the defect in the n-phase, inclusions of regular geometric shape are observed, the location and dimensions of which indicate that they adhere to the coating at the moment of attraction of the product from the melt. The identification of the phase composition of inclusions was carried out using EDS (energy-dispersive X-ray spectroscopy) and EBSD (Electron backscatter diffraction) analysis. It was found that the inclusions are a ζ-phase (isomorphic to FeZn13), containing about 0.8% (by weight) nickel. It is shown that the main causes of the formation of the "grain" defect are the appearance of floating waste particles in the melt caused by contamination of the zinc melt with iron, as well as a local excess of the recommended nickel concentration. Methods of preventing defects of the considered type of species during hot galvanizing are proposed.

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