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SiO₂ and SiO₂-ZrO₂ nanocomposites were coated by sol–gel dipping method on carbon steel 178 (178 CS). Nanostructure and phase properties of nanocomposite coating were characterized using X-ray diffraction, scanning electron microscopy and Fourier transform infrared studies. Electrochemical polarization and electrochemical impedance spectroscopy (EIS) tests were used to study the corrosion behavior of 178 CS that was coated with SiO₂-ZrO₂ nanocomposite and SiO₂ coating in 3.5 per cent NaCl solution. The results indicated that SiO₂-ZrO₂ nanocomposite coating performed better in terms of corrosion resistance compared with SiO₂ coating. The corrosion resistance of SiO₂-ZrO₂ nanocomposite coating could be increased significantly in by approximately three and seven times of that of SiO₂ coating and bare 178 CS, respectively.

SiO₂ and SiO₂-ZrO₂ nanocomposites were coated using sol–gel dipping method on carbon steel 178. Electrochemical polarization and EIS tests have been used to study the corrosion behavior of 178 CS that was coated with SiO₂-ZrO₂ nanocomposite and SiO₂ coating in 3.5 per cent NaCl solution.

Results indicated that SiO₂-ZrO₂ nanocomposite coating performed better in terms of corrosion resistance compared with SiO₂ coating. The corrosion resistance of SiO₂-ZrO₂ nanocomposite coating could be increased significantly in by approximately three and seven times of that of SiO₂ coating and bare 178 CS, respectively.

The SiO₂-ZrO₂ nanocomposite coating film showed significant improvement in corrosion resistance of 178 CS. The highest polarization resistance of the nanocomposite coating film was 10,600 Ω/cm² from SiO₂-0.2 ZrO₂.

The low resistance against penetration of water, oxygen and the other corrosive ions through the paths of coating is one the most important problems. So, protective properties of coating such as polyester must be promoted. Recently, the use of nanoparticles in the matrix of polymer coating to increase their protection and mechanical properties has been prospering greatly. The purpose of this study is to improve the corrosion resistance of the polyester powder coating with ZnO nanoparticles. The ZnO nanoparticles have been synthesized by hydrothermal method in a microwave. Using polyester – ZnO nanocomposite coating as powder – combining them by ball milling process and coating them by electrostatic process are innovative ideas and have not been used before it.

Polyester powder as the matrix and ZnO nanoparticles as reinforcing were combined in three different weight percentage (0.5, 1, 2 Wt.%), and they formed polymer nanocomposite by ball milling process. Then, the fabricated nanocomposite powder was applied to the surface of carbon steel using an electrostatic device, and then the coatings were cured in the furnace. The morphology of synthesized zinc oxide nanoparticles was investigated by transmission electron microscope. Also, the morphology of polyester powder and fabricated coatings was studied by scanning electron microscope. The effects of zinc oxide nanoparticles on the corrosion resistance of coated samples were studied by electrochemical impedance spectroscopy (EIS) test at various times (1-90 days) of immersion in 3.5 per cent NaCl electrolyte.

Scanning electron microscopy (SEM) results reveal that there are no obvious crack and defects in the nanocomposite coatings. In contrast, the pure polyester coatings having many cracks and pores in their structure. According to the EIS results, the corrosion resistance of nanocomposite coating compared to pure coating is higher. The value obtained from EIS test show that corrosion resistance for coating that contains 1 Wt.% nanoparticle was 32,150,000 (Ωcm²), which was six times bigger than that of pure coating. In addition to providing a barrier against diffusion of electrolyte, ZnO nanoparticles act as a corrosion inhibitor and, thus, increases the corrosion resistance. The corrosion resistance of coating containing 0.5 Wt.% nanoparticles was lower as compared to that of 1 Wt.% nanoparticles. The low content of nanoparticles caused partial covering of the porosity of coating which in turn leads to provide weaker barrier properties. The increase in quantity of nanoparticles from 1 to 2 Wt.% also caused a decrease in corrosion resistance which is attributed to the agglomeration of nanoparticles.

The results of this study indicated the significant effect of ZnO nanoparticles on the protective performance and corrosion resistance of the polyester powder coating. Evaluation of coating surface and interface with SEM technique revealed that nanocomposite coating compared with pure polyester coating provided a coating with lower number of pores and with higher quality. The EIS measurements represented that polymeric coating that contains nanoparticles compared to pure coating provides a better corrosion resistance. In addition to providing a barrier against diffusion of electrolyte, ZnO nanoparticles act as a corrosion inhibitor and thus increase the corrosion resistance. The corrosion resistance of coating containing 0.5 Wt.% nanoparticles was lower as compared to that containing 1Wt.% nanoparticles. The low content of nanoparticles caused partial covering of the porosity of coating which in turn leads to provide weaker barrier properties. The increase in quantity of nanoparticles from 1 to 2 Wt.% also caused a decrease in corrosion resistance which is attributed to the agglomeration of nanoparticles.

The purpose of this paper is to investigate the effect of TiO₂ nanoparticle content on the corrosion behavior of Ni‐Cr/TiO₂ nanocomposite coatings applied by pulse‐reverse electroplating.

Ni‐Cr/TiO₂ nanocomposite coatings with various contents of TiO₂ nanoparticles were electrodeposited by pulse‐reverse method from a bath containing TiO₂ nanoparticles to be codeposited and citric acid as the complexing agent. The surface morphology and the composition of coatings were studied by scanning electron microscopy (SEM) equipped by energy dispersive X‐ray system (EDS). The corrosion performance of coatings in the 0.5 M NaCl as a corrosive solution was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods.

It was found that the surface of Ni‐Cr/TiO₂ nanocomposite coatings showed a finer structure that was more uniform and compact in appearance than was that of Ni‐Cr coatings. The incorporation of TiO₂ nanoparticles in the alloy coating matrix improved the corrosion performance of the coatings and the higher content of nanoparticles gave better corrosion resistance.

Applying the Ni‐Cr coatings by the pulse‐reverse plating method eliminated cracks that were a problem in the Ni‐Cr alloy coating structure. Furthermore, the corrosion resistance was improved by the addition of TiO₂ nanoparticles to the alloy matrix. This paper reports the optimum plating conditions that gave the better corrosion performance.

This paper aims to study the effect of SiO₂ nano‐particulates on the corrosion behaviour of Ni‐W/SiO₂ nanocomposite coatings.

Weight loss measurements, electrochemical measurements and scanning electron microscope were used to study the corrosion behaviour of Ni‐W/SiO₂ nanocomposite coatings in NaCl solution.

The incorporation of SiO₂ nano‐particulates into the Ni‐W alloy matrix significantly increased the corrosion resistance. The improvement in corrosion resistance was due to the SiO₂ nano‐particulates acting as physical barriers to the corrosion process by filling in crevices, gaps and microscopic holes on the surface of the Ni‐W alloy.

This study highlights the use of nano‐particulates for the control of Ni‐W alloy coating corrosion and opens a new route for industry in the anti‐corrosion field.

Polypyrrole (PPy) and PPy/metal oxide nanocomposites were synthesized by oxidative polymerization process, and its corrosion protection ability was studied by immersion test and electrochemical corrosion studies in 1 per cent HCl and 3.5 per cent NaCl solution.

The prepared composites were loaded in acrylic resin and subsequently coated on a mild steel surface. The characterization of the polymer composites using FT-IR, UV-vis, XRD and FE-SEM with EDS analysis confirmed the interaction between PPy and metal oxide nanoparticles. The PPy nanoparticles were less protected on the mild steel, but the nanocomposite coating with metal oxide nanoparticles dramatically increased the corrosion resistance.

According to the corrosion protection ability of the coating, it was demonstrated that the acrylic resin coating composed of PPy/metal oxide nanocomposites was highly efficient in protecting the mild steel compared to the PPy nanoparticles. The highest protection efficiency was obtained by PPy/TiO2 nanocomposites with acrylic resin coating.

To the best of the authors’ knowledge, this paper consists of original, unpublished work which is not under consideration for publication elsewhere and that all the co-authors have approved the contents of this manuscript and submission.

This study aims to explore how the inhibitor-loaded nanocontainers can be used in the epoxy coating for protection of steel against corrosion. A self-healing anticorrosive coating can be easily fabricated by embedding the inhibitor-loaded nanocontainers into the epoxy coating matrices. For this purpose, first, cerium (a catholic corrosion inhibitor) is encapsulated into silica nanoparticles (SiO₂@Ce). Thereafter, an epoxy nanocomposite coating has been prepared on steel substrate using these SiO₂@Ce nanoparticles as nanofillers.

To examine the effect of SiO₂@Ce nanocontainers on mechanical properties of epoxy coating, the abrasion resistance, impact resistance and adhesion strength of coating have been evaluated. To reveal the effect of SiO₂@Ce nanocontainer on corrosion behavior of epoxy-coated steel, the electrochemical impedance spectroscopy (EIS) has been conducted in NaCl solution.

Transmission electron microscopy and scanning electron microscopy/Energy-dispersive X-ray spectroscopy analyses indicate that Ce³⁺ cations have been successfully loaded into the surface of silica nanoparticles (at the content of approximately 2 Wt.%). Mechanical tests of epoxy nanocomposite coatings indicate that the nanocomposite coatings with nanoparticles content of 2.5 Wt.% provide the highest values of abrasion resistance, impact resistance and adhesion strength. EIS results show that the presence of SiO₂@Ce³⁺ nanocontainers increases both coating resistance and polarization resistance. Along with the improvement the coating barrier performance, Ce inhibitor plays an important role in improving the anticorrosive performance at the steel–electrolyte interface.

The application of self-healing epoxy/SiO₂@Ce nanocomposite coatings for the protection of carbon steel is very promising.

The main aim of this study was to improve current efficiency and to obtain thicker coatings via aluminum oxide (Al₂O₃) addition to the chromium (Cr) (III) bath.

Pure Cr and nanocomposite Cr–Al₂O₃ coatings were electrodeposited from Cr (III) bath onto cathode copper substrates by conventional method. Dependence of current efficiency to current density, Al₂O₃ content and particle size were investigated.

Current efficiency increased with Al₂O₃ amount and decreased with Al₂O₃ particle size. Maximum current efficiency was achieved at 25 A/dm₂ for pure Cr and 30 A/dm₂ for composite coatings. Al₂O₃ bath content, current density and stirring rate increased the coating Al₂O₃ weight per cent significantly. Addition of Al3+ bath composition inhibited nanoparticle agglomeration, increasing film homogeneity. Cr–Al₂O₃ nanocomposites showed higher microhardness and better corrosion resistance than pure Cr layer.

Cr (III) is not as toxic and as carcinogenic as Cr (VI) which is widely used for Cr electroplating these days. Low current efficiency and poor product quality are, however, major drawbacks of the former. This paper describes significant improvements obtainable by addition of Al₂O₃ nanoparticles to the Cr (III) bath for increasing the microhardness, the corrosion resistance and the current efficiency of the deposition.

This work aims to prepare and characterize of protective anticorrosion phosphate-doped polyaniline (PANI) nanocomposite coatings for stainless steel (SS) in chloride solution.

PANI composite coatings were electrodeposited from aqueous sulfuric acid solution containing monomer and Al₂O₃ nanoparticles using cyclic voltammetry technique. Doping by phosphate was done by aging the coated steels for different periods (1–168 h) in phosphate solution. The polymer film composite was investigated by Fourier-transform infrared spectroscopy and scanning electron microscopy techniques. Potential-time, anodic polarization and electrochemical impedance spectroscopy were used to study the protection efficiency of the coatings.

The Al₂O₃ nanoparticles were incorporated into the deposited PANI layer but they decreased the deposition of polymer. The nanoparticles and the phosphate anions enhanced the protective PANI layer for passivation and protection of SS in the chloride solution.

The replacement of counter anions by phosphate ions improved significantly the PANI and its nanocomposite as protective coating of SS in chloride solution.

Ti-Si-N coating with nanocomposite structure is a promising protective coating for cutting tools which will be subject to high temperature oxidation during service. This study aims to investigate the thermal stability of Ti-Si-N coatings and lays the foundation for its application in high speed dry cutting.

Nanocomposite Ti-Si-N coating was deposited on stainless substrate and silicon wafer (100) by Ti90Si10 alloy target by using cathodic arc ion plating. The microstructure of Ti-Si-N coating had been detected by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS).

The results suggested that the coating was TiN nanocrystals with a diameter of 6.3 nm surrounded by amorphous Si3N4. The oxidation test was conducted under 550, 650, 750, 800, 850, 900 and 950°C for 2 h. The structure evolution was observed by Scanning electron microscope (SEM), energy dispersive spectrum (EDS), XRD and XPS. The results indicated that rutile has been formed at 650°C, while Si3N4 began to oxidized at 800°C. The grain size of TiN increased from 6.3 to 13 nm as the samples oxidized from 550 to 800. Micro-crack also formed in samples oxidized over 900°C.

Ti-Si-N coating, in this study, was deposited by cathodic arc ion plating using alloy target at high-bias voltage. The oxidation temperature ranged from 500 to 950°C with TiN coating as reference.

Inorganic oxide addition can be synergistically beneficial in organic coatings if it can impart anti-corrosion properties and also act as an additive to enhance physical and/or chemical properties. The aim of this study was to evaluate the anti-corrosion benefits of nano nickel zinc ferrite (NZF) in the polymer film.

The time-dependent anti-corrosion ability of NZF (0.12-1.0 per cent w/w NZF/binder), applied on API 5L X-80 carbon steel, was characterized by electrochemical techniques such as open circuit potential, electrochemical impedance spectroscopy, linear polarization resistance and potentiodynamic. Characterization of corrosion layer was done by removing coatings after 216 h of immersion in 3.5 per cent w/v NaCl. Optical microscopy, field emission scanning electron microscopy and X-ray diffraction techniques were used to characterize the corroded surface.

Corrosion measurements confirm the electrochemical activity by metallic cations on the steel surface during corrosion process which results in improvement of anti-corrosion properties of steel. Moreover, surface techniques show compact corrosion layer coatings and presence of different metallic oxide phases for nanocomposite coatings.

The suggested protection mechanism was explained by the leaching and precipitation of metallic ion on the corroded surface which in turn slowed down the corrosion activity. Furthermore, improvement in barrier properties of rubber-based coatings was confirmed by the enhanced pore resistance. This work indicates that along with a wide range of applications of NZF, anti-corrosion properties can be taken as an addition.