Search results

Immersion is one of the key steps during the preparation of silane-based hybrid films, which has important effects on the performance of films after curing. In this paper, the formation process of Zr-doped silane film (i.e. the adsorption of silane and deposition of zirconium compounds) on carbon steel immersed in Zr(NO₃)₄/silane mixed solutions was investigated.

The method of in situ monitoring the open circuit potential of a two-electrode system, consisting of carbon steel and saturated calomel electrode, was used. The effects of immersion conditions (i.e. the concentration of Zr(NO₃)₄ and pH of Zr(NO₃)₄/silane mixed solution) on the open circuit potential were investigated in detail. Furthermore, the surface coverage rate of different cured films (i.e. Zr cured film, silane cured film and Zr/silane composite cured film) after curing on carbon steel was calculated according to the results of polarization curves. Electrochemical impedance spectroscopy (EIS) was used to study the self-healing property of Zr-doped silane cured film.

The results indicate that in Zr(NO₃)₄/silane mixed solutions, most zirconium compounds deposit on the surface of carbon steel at the initial immersing stage, then the adsorption of silane on the residual surface of carbon steel dominates the following immersing stage. EIS results show that the Zr-doped cured film has improved self-healing property.

First, the method of in situ monitoring the open-circuit potential of two-electrode system was applied to investigate the deposition of Zr and the adsorption of silane on carbon steel immersed in Zr(NO₃)₄/silane mixed solutions. Second, the formation process of Zr-doped silane film was proposed.

This paper aims to investigate the effect of cerium modification and electrodeposition on the properties of the silane films obtained. Besides, the influence of dissolved oxygen was also researched through inhalation of oxygen or nitrogen. Moreover, the corresponding corrosion behavior of the silane films was also studied.

In this paper, surface morphology and corrosion-resistant properties of the films were characterized by scanning electron microscopy, electrochemical impedance spectroscopy, immersion test and the salt spray test.

The paper reveals that all the practical parameters including the concentration of dissolved oxygen had a marked effect on the anti-corrosive performance of the films, which may be attributed to the dense and compact structure of the films obtained. Furthermore, the self-healing ability of the films had also been enhanced through the rise of dissolved oxygen concentration in proper proportion.

This paper reveals the effect of practical parameters on the properties of the silane films obtained and the corrosion behavior of these films.

Investigates the adhesion and corrosion performance of selected silanes in primed galvanised steel. For comparison HDG steel was also treated with a chromate‐free and a chromate‐containing pre‐treatment. All treated panels were painted with three different primers. Corrosion resistance and paint adhesion of the primed panels were studied. Surface energy of the panels was measured by the contact angle method and is reported in terms of the Lewis base component. The corrosion resistance of the panels depended on the combination of the silane and the primer. Vinyltrimethoxysilane (VS) and γ‐aminopropyltriethoxysilane (γ‐APS) treatments improved the corrosion resistance of polyurethane primed panels. γ‐ureidopropyltrimethoxysilane (γ‐UPS) and VS treatments improved the performance of polyester primed panels. A relationship between the base components and the prohesion test results of γ‐UPS and γ‐APS treated panels was found, which indicates that acid‐base interactions improve the adhesion between these two silanes and the primers. γ‐UPS and γ‐APS treated panels also achieved excellent results in the humidity test with all three polymer coatings.

The purpose of this paper is to improve the corrosion resistance of anodized 6063 Al alloy inertial air–water separator by means of silane technology and to investigate the effect of corrosion-generated surface roughness changes on aerodynamic performance.

The BTSE-KH560 double-layer silane film treatment technique is used to close micropores on the anodic oxide film surface. The microstructure of the coating is observed by scanning electron microscopy, the coating structure of the specimens is determined by X-ray diffraction (XPS) and the corrosion resistance is determined by electrochemical and salt-spray tests. Computational fluid dynamics is also used to calculate the effect of roughness and analyse the change in separator performance.

The silane film deposited on the surface of the anodic oxide film acts as a good seal against microporous defects on the surface of the anodic oxide film and reduces the surface roughness. Electrochemical and salt-spray tests show that the silane film improved the corrosion resistance of the anodized film. The roughness produced by the corrosion deteriorates the performance of the separator.

The porous structure of the anodized coating makes it easier for corrosive ions to enter the substrate and cause pitting corrosion. Therefore, in this study, the corrosion behaviour of the coating in the marine environment and its effect on aerodynamic performance are investigated using a BTSE-KH560 double-layer silane coating with a sealing effect.

The application of coatings on metal substrates can provide an increase in corrosion resistance in the environment where the material is employed. The use of silane causes low environmental impact and may represent an alternative to replace chromates and phosphates applied as a pretreatment prior to surface painting. The objective of this study was to evaluate experimental parameters for the investigation of the formation of a vinyltrimethoxysilane (VTMOS) monolayer on 1010 carbon steel applying electrochemical techniques.

A total of 24 types of coated samples were obtained, following three 2³ factorial design of experiments (DOE), and one uncoated. The VTMOS monolayer was formed by hand dip process, followed by curing in a stove, using substrates of sanded, pickled and degreased 1010 carbon steel and hydrolyzed silane.

The results of coated samples were satisfactory as compared to those of uncoated carbon steel, as the former were better protected against corrosion.

This paper shows an evaluation of experimental parameters that influence the formation of a film of silane VTMOS on 1010 carbon steel by means of electrochemical techniques. The results indicated that the silane monolayer VTMOS promotes enhanced properties that prevent corrosion of 1010 carbon steel and the method of film formation directly influences the properties of such protection.

The purpose of this paper is to evaluate and compare the protective, anticorrosion properties of silane- and polyrhodanine-based bilayer coatings pRh/IBTES and IBTES/pRh on an X20Cr13 stainless steel substrate.

IBTES/pRh and pRh/IBTES have been coated using the dip-coating method and the cyclic voltammetry technique. The electrochemical measurements have been used to assess the anticorrosion properties of the resulting bilayer coatings. Morphological and chemical characterizations have been performed using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS).

The results clearly show that the combination of both the deposits of polyrhodanine and silane yields a more protective structure that affords better protection against corrosion with time. The best barrier properties are achieved by the substrates coated with polyrhodanine film upon which silane is subsequently adsorbed – the pRh/IBTES bilayer coating.

The paper reveals that the procedure of modification of silane films with polyrhodanine had a marked effect on the anti-corrosive performance of the obtained two types of bilayers coatings (pRh/IBTES, IBTES/pRh) applied on a stainless steel surface. The coating where polyrhodanine was first electrodeposited on the steel surface and then the silane layer adsorbed (pRh/IBTES) achieved the best protective properties.

This paper aims to improve the anti-corrosive properties of aluminum alloy AA2024-T3 by coating of hybrid sol-gel coating incorporated with TiO₂ nanosheets and to investigate the effect of nanosheets’ size on the improvement of corrosion-resistant performance.

A series of hybrid sol-gel films incorporated with varying amounts of TiO2 nanosheets were developed to enhance the corrosion protection performance of the bare metal. Scanning electron microscopy, transmission electron microscopy and atomic force microscopy were used to investigate the structure and morphology of the coatings obtained. In addition, the corrosion-resistant properties of the coatings were evaluated using salt spray test and electrochemical impedance spectroscopy.

The corrosion current was as low as 9.55 × 10-4 µA/cm² and optimal positive corrosion potential reached −0.6 V when the size and loading amount of TiO₂ nanosheet were optimized, resulting in a remarkable improvement in anti-corrosive properties.

This work first investigates the effect of incorporation of TiO₂ nanoparticles on hybrid sol-gel coating on the improvement of anti-corrosive performance of aluminum alloy AA2024-T3.

The purpose of this paper is to study the compound effect between silane and cerium salts in the passivation process of chemical conversion treatment of zinc.

Chemical conversion treatment using 3‐Glycidoxypropyltrimethoxysilane on zinc is investigated as an alternative treatment to chromate conversion. The surface chemistry of the silane‐treated samples is investigated with mass change measurements, polarization curves, electrochemical impedance spectroscopy (EIS) and the salt spray tests (SST). The surface morphology of samples was studied using a scanning electron microscope.

The polarization curves, EIS and SST data are in agreement. On the surface of zinc, the silane formed a compound with the cerium, thus enhancing the adhesion and corrosion resistance of the polymer film.

There have been few reports on the compound effects of silanes and cerium salts in the passivation process. The mechanism of this compound effect may be due to the ability of Ce^3 +ions to gain access to the interface through tiny cracks or micropores in the cross‐linking structure of GPS polymer films on zinc, and the subsequent oxidation of Ce^3 +to Ce^4 +by H₂O₂ may result in a barrier effect between the electrolyte and the metallic substrate.

The purpose of this paper is to improve binding force between the coating and the steel substrate by using chemical modification on the steel surface; at the same time, it can also increase the corrosion resistance of the coating.

The main components of the conversion film include tannic acid, sodium molybdate and silane coupling agent KH560. After the preparation was completed, the samples were tested and analyzed, including surface morphology, conversion film components, bonding force with organic resins and corrosion resistance. Finally, it drew a conclusion that the conversion film can greatly improve the bonding strength of the steel substrate and epoxy resin.

When the content of tannic acid is 4 g/L meanwhile the content of KH560 is 20 g/L, the conversion film has the strongest binding force with epoxy resin, from 2.15 Mpa of untreated steel to 4.60 Mpa, growth of 140 per cent. At the same time, the resulting conversion film also improves the corrosion resistance of the steel surface by a small margin.

A method of enhancing the bond between an epoxy coating and steel is provided. Verify the mechanism of this method.

This paper aims to access the protective function of hybrid sol-gel coatings deposited on 304L stainless steel substrate in silane solutions containing a mixture of tetraethoxysilane, methyltriethoxysilane and glycidyloxypropyltrimethoxysilane with different pH values during various immersion periods.

The 304L stainless steels coated through 10 and 30 s of immersion in the silane solutions with pH values of 2.1 and 2.8 were exposed to NaCl solution. The corrosion resistance of the coated substrates was studied through taking advantage of electrochemical noise method as well as atomic force microscopy (AFM), water contact angle and field emission-type scanning electron microscopy (FESEM) surface analysis.

The electrochemical current noise, PSD (I) plot, noise resistance and characteristic charge as parameters extracted from electrochemical noise method indicated the superiority of eco-friendly silane coating deposited on the substrate surface during 10 s exposure to the solution, due to the film uniformity and homogeneity as confirmed by FESEM and AFM. Moreover, immersion of the stainless steel in the silane solution with pH 2.1, characterized by higher hydrolysis ratio, led to more effective corrosion control in the NaCl electrolyte according to the results of electrochemical noise and FTIR measurements.

The noise resistance and characteristic charge as electrochemical noise parameters were only used in this research to evaluate the protective behavior of the water-based silane sol-gel coatings. Future studies should examine the correlation between electrochemical noise data and the parameters extracted from other electrochemical methods, e.g. electrochemical impedance spectroscopy.

The data obtained in this research may provide an effective approach based on electrochemical noise method to screen the silane sol-gel coatings for protection of metallic substrates against corrosion.

According to the literature, no report can be found studying the effect of immersion time on a silane solution, including glycidyloxypropyltrimethoxysilane, tetraethoxysilane and methyltriethoxysilane, as well as the silane solution pH on the corrosion resistance of 304L stainless steel in NaCl solution through electrochemical noise method.