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This paper aims to focus on the research progress of intelligent self-healing anti-corrosion coatings in the aviation field in the past few years. The paper provides certain literature review supports and development direction suggestions for future research on intelligent self-healing coatings in aviation.

This mini-review uses a systematic literature review process to provide a comprehensive and up-to-date review of intelligent self-healing anti-corrosion coatings that have been researched and applied in the field of aviation in recent years. In total, 64 articles published in journals in this field in the last few years were analysed in this paper.

The authors conclude that the incorporation of multiple external stimulus-response mechanisms makes the coatings smarter in addition to their original self-healing corrosion protection function. In the future, further research is still needed in the research and development of new coating materials, the synergistic release of multiple self-healing mechanisms, coating preparation technology and corrosion monitoring technology.

To the best of the authors’ knowledge, this is one of the few systematic literature reviews on intelligent self-healing anti-corrosion coatings in aviation. The authors provide a comprehensive overview of the topical issues of such coatings and present their views and opinions by discussing the opportunities and challenges that self-healing coatings will face in future development.

The purpose of this study is to investigate the structural, surface roughness and corrosion properties of the zirconium oxide thin films deposited onto SS304 substrates using the direct current (DC) magnetron sputtering technique.

DC sputtering at different powers – 80, 100 and 120 W – was used to deposit ZrO₂ thin films onto different substrates (Si/SS304) without annealing of the substrate. Atomic force microscope (AFM), energy-dispersive X-ray spectroscopy (EDS), Tafel extrapolation and contact angle techniques were applied to investigate the surface roughness, chemical compositions, corrosion behavior and hydrophobicity of these films.

Results showed that the thickness of the deposited film increased with power increase, while the corrosion current decreased with power increase. AFM images indicated that the surface roughness decreased with an increase in DC power. EDS analysis showed that the thin film has a stoichiometric ZrO₂ (Zr:O 1:2) composition with basic uniformity. Water contact angle measurements indicated that the hydrophobicity of the synthesized films decreased with an increase in surface roughness.

DC magnetron sputtering technique is infrequently used to deposition thin films. The obtained thin films showed good hydrophobic and anticorrosion properties. Finally, results are compared with other deposition techniques.

Here, diazo coupling reaction was imparted on chemically inert lignin isolated from natural resources. Activated lignin was coupled with the diazotised aniline, m-nitroaniline, p-nitroaniline-, and p-anisidine gives organic pigments.

The continuous increase in particle size of pigments confirms addition of diazotised salt to lignin by coupling reaction. Further, the dispersing ability of these coloured pigments were exploited in polymer matrix. Epoxy-polyamine cross linking system was doped with difference percentage of pigments and coated on mild steel metal surface. The morphology of these composites was understood by SEM, particle size, differential scanning calorimeter and thermo gravimetric analysis.

The synthesised organic pigments were characterised by FT-IR, ¹H NMR and UV-visible spectroscopy. It was observed that hiding power of aniline- and m-nitroaniline–based azo pigments was more than p-nitroaniline- and p-anisidine–based azo pigments. Thermal properties as well as water contact angles of coatings were improved with pigment concentration. The chemical resistivity of coating was observed to be improved with the increasing % of lignin-based azo pigment.

Lignin-based azo pigment has great potential to replace metal oxide pigment and provide strategy for utilisation of lingo-cellulosic biowaste material.

This paper aims to study the corrosion inhibition behavior of imidazopyridine and its three derivatives on brass.

The authors performed weight loss experiments, electrochemical experiments including the polarization curve and electrochemical impedance spectrum, corrosion morphology observation using scanning electron microscope (SEM) and atomic force microscope (AFM) and surface composition analysis via X-ray photoelectron spectroscopy (XPS) to analyze the corrosion inhibition behavior of imidazopyridine and its three derivatives on brass by using quantum chemical calculation (Gaussian 09), molecular dynamics simulation (M-S) and Langmuir adsorption isotherm.

According to the results, imidazole-pyridine and its derivatives were found to be modest or moderately mixed corrosion inhibitors; moreover, they were spontaneously adsorbed on the metal surface in a single-layer, mixed adsorption mode.

The corrosion inhibition properties of pyrazolo-[1,2-a]pyridine and its derivatives on brass in sulfuric acid solution were analyzed through weight loss and electrochemical experiments. Moreover, SEM and AFM were simultaneously used to observe the corrosion appearance. Furthermore, XPS was used to analyze the surface. Then, Gaussian 09 and M-S were combined along with the Langmuir adsorption isotherm to investigate the corrosion inhibition mechanism of imidazole-[1,2-a]pyridine and its derivatives.

Two corrosion inhibitors for closed cooling water systems, nitrite-based and mixture of nitrite and molybdate corrosion inhibitor, are often compared to each other. This study aims to optimize these two inhibitors in terms of concentration and pH for carbon steel protection, with insights into the double layer structure on surface and its impact on corrosion inhibition.

Electrochemical analysis including electrochemical impedance spectroscopy and potentiodynamic test are carried out for quick assessment of corrosion inhibition efficiency and optimization, which is confirmed by immersion test and microscopic analysis. The electronic properties of the surface film are analyzed through Mott–Schottky method which provides new insights into the inhibition mechanism and the role of each component in mixture inhibitor.

Mixture of nitrite and molybdate is shown to present higher inhibition efficiency, owning to the double layer structure. Nitrite alone can form a protective surface film, whereas molybdate leads to an n-type semiconductive film with lower donor density, hence giving rise to a better inhibition effect.

Surface after inhibitor treatment has been carefully characterized to the microscopic scale, implying the effect of micro-structure, chemical composition and electronic properties on the corrosion resistance. Inorganic corrosion inhibitors can be tuned to provide higher efficiency by careful design of surface film structure and composition.

Almost every study on corrosion inhibitor applies such method for quick assessment of corrosion inhibition effect. Mott–Schottky test is one of electrochemical methods that reveals the electronic properties of the surface film. Previous works have studied the surface layer mainly through X-ray photoelectron spectroscopy. This study provides another insight into the surface film treated by nitrite and molybdate through Mott–Schottky analysis, and relates this structure to the corrosion inhibition effect based on multiple analysis including electrochemistry, microscopic characterization, thermodynamics and interface chemistry.

The purpose of this study is to investigate the initial corrosion behavior of pure Mg, AZ31 and AZ91 alloys in phosphate buffer solution (PBS) and to characterize the features in corrosion type and resistance of the corrosion product layer.

The scanning electron microscopy, equipped with energy-dispersive spectroscopy, X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy have been used to characterize the as-corroded samples. Besides, the Mg²⁺ concentration in PBSs has been determined by inductively coupled plasma atomic emission spectrum.

It has been found that pure Mg suffers pit corrosion, and AZ31 initially undergoes pit corrosion and then uniform corrosion dominates with an extended immersion duration. However, AZ91 exhibits the uniform corrosion with the highest corrosion rate among the three materials. Besides, the corrosion product layer on AZ31 has the best compactness and corrosion resistance.

The findings add depth in understanding the corrosion of pure Mg and its alloys in PBS and also have guiding significance in exploring the effects by alloyed elements to develop new biomaterials with better performance.

The purpose of this paper is to explore the effect of ZnO on the structure and properties of micro-arc oxidation (MAO) coating on rare earth magnesium alloy under large concentration gradient.

The macroscopic and microscopic morphology, thickness, surface roughness, chemical composition and structure of the coating were characterized by different characterization methods. The corrosion resistance of the film was studied by electrochemical and scanning Kelvin probe force microscopy. The results show that the addition of ZnO can significantly improve the compactness and corrosion resistance of the MAO coating, but the high concentration of ZnO will cause microcracks, which will reduce the corrosion resistance to a certain extent.

When the concentration of zinc oxide is 8 g/L, the compactness and corrosion resistance of the coating are the best, and the thickness of the coating is positively correlated with the concentration of ZnO.

Too high concentration of ZnO reduces the performance of MAO coating.

The MAO coating prepared by adding ZnO has good corrosion resistance. Combined with organic coatings, it can be applied in corrosive marine environments, such as ship parts and hulls. To a certain extent, it can reduce the economic loss caused by corrosion.

The effect of ZnO on the corrosion resistance of MAO coating in electrolyte solution was studied systematically, and the conclusion was new to the common knowledge.

This study aims to improve the corrosion resistance of TA2-welded joints by superhydrophobic surface modification using micro-arc oxidation technology and low surface energy substance modification.

The microstructure and chemical state of the superhydrophobic film layer were analyzed using scanning electron microscopy, energy dispersive X-ray spectroscopy, three-dimensional morphology, X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared absorption spectroscopy. The influence of the superhydrophobic film layer on the corrosion resistance of TA2-welded joints was investigated using classical electrochemical testing methods.

The characterization results showed that the super hydrophobic TiO₂ ceramic membrane was successfully constructed on the surface of the TA2-welded joint, and the construction of the super hydrophobic film greatly improved the corrosion resistance of the TA2-welded joint.

The superhydrophobic TiO₂ ceramic membrane has excellent corrosion resistance. The micro nanostructure in the superhydrophobic film can intercept air to form an air layer to prevent the corrosion medium from contacting the surface, thus, improving the corrosion resistance of the sample.

This study aims to determine the effect of replacing a portion of the cement in the concrete mixture with silica fume (SF) on the corrosion resistance of reinforcing bars, the compressive strength of concrete and the tensile strength of hook bars in both corroded and non-corroded external joints of structures. The external beam-column connection was studied because of its critical role in maintaining structural continuity in all three directions and providing resistance to rotation.

In external concrete joints, the bars at the end of the beams are often bent at 90° to form hooks that embed in columns. Owing to the importance of embedding distance and the need to understand its susceptibility to corrosion damage from chloride attack, a series of experiments were conducted on 12 specimens that accurately simulate real-site conditions in terms of dimensions, reinforcement and hook bars. SF was replaced with 10% and 15% of the weight of cement in the concrete mixture. To simulate corrosion, the specimens were subjected to accelerated corrosion in the laboratory by applying a low continuous current of 0.35 mA for 58 days.

The results revealed the effect of SF in improving the compressive strength of concrete, the pullout resistance of the hook bars and the corrosion resistance. In addition, it showed an apparent effect of the corrosion of reinforcing bars in reducing the bonding strength of hook bars with concrete and the effect of SF in improving this strength.

It was noted that the improvement of the results, achieved by replacing 10% of the weight of cement with SF, was significantly close to the results obtained by replacing 15% of the SF. It is recommended that an SF ratio of 10% be adopted to achieve the greatest economic savings.

The purpose of this paper is to study the effect of current-carrying condition on the electrochemical process and atmospheric corrosion behavior of the commercial aluminum alloys.

Potentiodynamic polarization tests were performed to study the electrochemical process of the aluminum alloys. Salt spray tests and weight loss tests were carried out to study the atmospheric corrosion behavior. The corrosion morphology of the alloys was observed, and the products were analyzed.

The corrosion process of four aluminum alloys was accelerated in the current-carrying condition. Moreover, the acceleration effect on A2024 and A7075 was much stronger than that on A1050 and A5052. The main factors would be the differences in microstructure and corrosion resistance between these alloys. As the carried current increased, the corrosion rate and corrosion current density of the aluminum alloys gradually increased, with the protection of the corrosion product film decreasing linearly.

This is a recent study on the corrosion behavior of conductors under current-carrying condition, which truly understands the corrosion status of power grid materials. Relevant results provide support for the corrosion protection and safe service of aluminum alloy in power systems.