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To promote the anticorrosion performance of epoxy/zinc (EP/Zn) coating, graphene oxide (GO) was directly incorporated into dual-component paint. Interestingly, it was found that the method of incorporating GO during the fabrication of the composite paints strongly influenced their performance. The samples were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and Raman spectroscopy. The results indicated that GO could be intercalated and modified with the polyamide curing agent while preparing component B of the paint, for which the interlayer spacing of the resulting polyamide modified GO (PGO) increased, and its dispersion in organic solvent was improved. The corrosion resistance of the coatings was studied through potentiodynamic polarization testing, electrochemical impedance spectroscopy (EIS), and immersion testing. Among the three types of as-prepared coatings, i.e., neat EP/Zn coating, GO modified EP/Zn coating (GO/EP/Zn), and PGO-modified EP/Zn coating (PGO/EP/Zn), the order of the corrosion resistance of the coatings was PGO/EP/Zn > GO/EP/Zn > neat EP/Zn. This work demonstrates that although the in situ modification of GO with a curing agent is a simple method, it evidently promotes the shielding effect of the coating and enhances its corrosion resistance.

Zinc is a commonly used corrosion-resistant coating for steel surface protection. In this study, the ethylene carbonate-zinc chloride (EC-ZnCl 2 ) electrolyte systems are selected for zinc electrodeposition, and their ionic structure and properties were studied. The corrosion resistance of the electrodeposited zinc coatings obtained from 4EC-ZnCl 2 , 3EC-ZnCl 2 , and 2EC-ZnCl 2 systems was analyzed. Raman spectroscopic analysis shows that these EC-ZnCl 2 systems contain [Zn 2 Cl 6 ] 2− species. The relationship between conductivity, viscosity, and density with the temperature of EC-ZnCl 2 systems was provided. Scanning electron microscopy (SEM) and potentiodynamic polarization curve (Tafel) tests showed that when the deposition was carried out at –1.0 V and –1.2 V (vs. Ag/AgCl) for two hours, a uniform zinc coating with good corrosion resistance could be obtained.

This study investigated the microstructure and corrosion behavior of 30MnB5 hot-stamped steel after applying a zinc coating using the cold-spraying method followed by heat treatment (HT). Al-10 wt%Si coating is essential for improving the high-temperature corrosion resistance of 30MnB5 steel during the hot-stamping process. Before HT, the coating layer primarily consisted of Al, whereas after HT, Fe–Al-based intermetallic compounds were formed throughout the layer. The Zn in the coating layer applied using the cold-spraying method was not uniformly distributed before HT. However, during HT, the low-melting-point Zn melted and re-solidified, allowing it to combine with Fe diffusing from the substrate. Consequently, Zn–Al–Fe-based intermetallic compounds were formed on the surface of the coating layer. In the Zn-coated specimens, the current density near the corrosion potential tends to be lower than that of the Al–Si-coated specimens because Zn corrodes preferentially owing to its sacrificial anode effect, thereby protecting the underlying Al–Si-coated layer and steel.

The features of the growth and the structure of diffusion zinc coatings in the process of galvanizing in powders with nanocrystallized surface area, alloyed with iron, are studied. It is established that the increase in the iron content in the powder substantially increases the area of the zinc solid solution in iron at a constant speed rate of the layer of zinc-iron phases. This effect is accompanied by the change in the morphology of powder particles as a result of iron saturation.

This paper deals with the evaluation of the surface of structural steel whose samples were deliberately contaminated with transparent spray primer, adhesive label glue, and welding sprays prior to hot-dip galvanizing. The galvanized samples were studied by optical microscopy, GDOES, adhesion tests, and condensation humidity tests. The effect of surface contamination on the quality of the zinc coating was found to be significant. In some cases, the zinc coating is damaged (after contamination with welding sprays), in others, it is completely absent (after contamination with spray primer or adhesive label glue).

In this paper, hybrid coatings based on ZnO dispersion in water soluble chitosan oligosaccharides (COS) as dispersion medium were prepared. The obtaining procedure of anti-corrosion hybrid zinc-based coatings containing COS coated ZnO particles in the metal matrix has been described. The available ZnO particles coated with COS were observed by TEM and thereafter added to the starting electrolyte for electrodeposition of hybrid zinc coatings on low-carbon steel substrates. The newly developed objects were collated with ordinary zinc coatings concerning the peculiarities of the morphology, topography and hydrophilicity of the surface (SEM and AFM analyses, water contact angle measurements), as well as corrosion behavior and electrochemical characteristics (cyclic voltammetry, potentiodynamic polarization curves, polarization resistance measurements). XRD and XPS methods were applied for studying of the crystallographic structure, as well as chemical and phase composition of the newly appeared corrosion products during the corrosion treatment in the test medium. Protective parameters of the coatings were evaluated in chloride environment of 5% NaCl solution. The results showed the effect of the concentration of the COS coated ZnO particles on the crystallographic structure and on the anticorrosion stability of the hybrid coatings.

As vehicle body structures become stronger and part designs more complex for lightweight, controlling frictional properties in automotive press forming has gained critical importance. Friction, a key factor in formability, is influenced by variables such as contact pressure, sliding velocity, sheet strength, and coatings. This study investigates the friction characteristics of steels with tensile strengths of 340 MPa and 980 MPa, under galvanized (GI) and galvannealed (GA) zinc coatings. Experimental results reveal that asperity flattening, a significant factor in determining friction, increases with contact pressure normalized by tensile strength, particularly for GI-coated steels. However, the relationship between friction and surface flattening deviates from conventional expectations, with the friction coefficient initially rising with increased flattening area up to ~20% before decreasing as flattening progresses. These findings suggest that traditional empirical formulas may not fully capture friction behavior under specific conditions. By understanding this inflection point, where friction reduces under high contact pressure, the study provides valuable insights for optimizing formability and improving sheet metal forming processes, especially in scenarios where precise friction control is critical for producing high-quality automotive parts.

Electrodeposition of zinc (Zn) coatings on copper (Cu) substrates was conducted from choline chloride–ethylene glycol-based deep eutectic solvent under the temperatures varying from 323 to 343 K. The electrochemical behavior of Zn ions on Cu electrodes at different temperatures was studied through cyclic voltammetry and chronoamperogram testing. The obtained results illustrate that the electrodeposition of Zn coatings is a diffusion-controlled quasi-reversible process with an instantaneous two-dimensional nucleation and growth mechanism. The crystal structure and chemical composition analysis demonstrates that the electrodeposition from ChCl–EG–ZnCl 2 system is an effective strategy to achieve a Zn coating with high crystallinity and purity. The surface morphological analysis further reveals that the electroplated coatings are stacks of flake Zn grains. The dependence of the deposition behavior and quality of electroplated Zn coatings on temperature was studied systematically. The growth behavior of Zn grains is enhanced with increasing the temperature, but too high a temperature inevitably leads to the undesired coarsen microstructure instead. On the basis of the polarization curves and EIS testing results, the temperature was optimized at 333 K to obtain a Zn coating with superior corrosion resistance in 3.5 wt% NaCl solution to that of Zn coatings electroplated at other conditions.

The article contains the findings on impact of zinc coating specifications on corrosion resistance and service life of steels of various chemical composition used often in modern industries. Characteristics such as type, class, chemical compound and thickness of zinc-based coatings are also addressed. Experiments were performed in which corrosion rate and useful life of zinc coatings in probable operating-like conditions — i.e., in environments of varying degrees of corrosive power (humid and high-chloride environments) were determined. It has been established which one of the environments is the most corrosive for steels depending on the zinc-based coatings’ specifications. Qualitative (visual) and quantitative (gravimetric) assessment of corrosion resistance and service life of chosen steels is presented. Optimal hot dip galvanized coating specifications were determined using statistical analysis.

The cathodic protection provided by epoxy coating/epoxy zinc-rich coatings on defective areas under atmospheric and immersion conditions was studied via a Q235 wire beam electrode (WBE), scanning electron microscopy, X-ray diffraction, and surface morphology analysis. The results showed that the cathodic protection processes under the two test conditions displayed significant differences. The effective protection time of the defective area under the atmospheric condition was 1.7 times that under the immersion condition. Compared with the immersion condition, zinc particles in zinc-rich coatings under the atmospheric condition exhibited higher cathodic protection efficiency. The possible activation mechanism of zinc particles under the two conditions was elucidated.