Anticorrosive Coatings Research Articles

Import Substitution of Anticorrosive Protective Coating of Pile Products of Hydraulic Structures Erected in the Arctic

Import Substitution of Anticorrosive Protective Coating of Pile Products of Hydraulic Structures Erected in the Arctic

Unveiling the anti-corrosion properties of Zn-eggshell particle composite coatings on mild steel in seawater-simulated solution using starch as a modifier.

This study investigates the development and efficacy of Zn-eggshell particle (ESAp) coatings on mild steel, utilizing starch extract as a modifier to enhance anti-corrosion properties. Coatings with varying ESAp content (0, 2, 4, 6, and 8%) and a fixed addition of 2% starch were successfully applied via electrodeposition. The findings reveal that increasing the ESAp content results in thicker coatings, with the Zn-8% ESAp + 2% starch coating exhibiting the greatest thickness. SEM analysis confirmed the high quality of the coatings, showing no external surface defects. The Zn-8% ESAp + 2% starch-coated sample demonstrated a 46.45% increase in hardness (100.3 HB) and achieved superior corrosion protection efficiencies of 82.92% and 94.69% for Zn-8% ESAp and Zn-8% ESAp + 2% starch coatings, respectively. Electrochemical tests indicated that the coated samples shifted towards higher positive potential values, suggesting enhanced corrosion resistance. The results underscore the potential of using starch extract and waste eggshells to develop robust anti-corrosion coatings, with Zn-8% ESAp + 2% starch identified as the optimal formulation for superior protection and mechanical properties. Further research is recommended to explore the matrix-particle interactions and adhesion properties using advanced microscopic and electrochemical techniques.

Fabrication of polyaniline/waste sugarcane bagasse composite fillers for excellent anti-corrosion protective coatings

Herein, biomass-based anti-corrosion composite fillers for water-based epoxy resin coatings, epoxy resin powder coatings, and efficient anticorrosive coatings were successfully prepared.

Exploring the Potential of Graphene in Real-Life Industrial Anticorrosive Coatings

Exploring the Potential of Graphene in Real-Life Industrial Anticorrosive Coatings

Versatile ionic liquid gels formed by dynamic covalent bonding and microphase separated structures.

It is challenging for ionic liquid gels to achieve the combination of rapid self-healing with high toughness. Here, ionic liquid gels (DI-PR) were prepared from readily available materials. A dynamic covalently bonded oxime-carbamate was prepared from polycaprolactone diol, isophorone diisocyanate and dimethylethyleneglyoxime, followed by addition of the "rigid-flexible" cross-linking agent rutin to chemically cross-link the polymer chains and afford the ionic liquid gels, DI-PR. The tensile strength, elongation at break and toughness of the DI-PR gels were as high as 16.5 MPa, 1132.6%, and 52.6 MJ m-3, respectively. The toughness is similar to that of natural silkworm silk (70 MJ m-3) and wool (60 MJ m-3). After stretching, the DI-PR can rebound within 1 s, their room temperature self-healing rate is as high as 92%, they remain functional over the temperature range -50 °C to 140 °C and the interface with a steel plate has an adhesion toughness of >2000 J m-2. These properties mean that the DI-PR gels are particularly suitable for use as anticorrosion coatings for submarine and underground gas and oil pipelines. The use of rutin, which combines rigid quercetin-based structural units with flexible glycoside-based structural units, as a cross-linking agent, provides a new method for improving the toughness of soft materials through its synergistic interaction with hard and soft chain fragments of polyurethanes.

Analyze the Performance of Electroactive Anticorrosion Coating of Medical Magnesium Alloy Using Deep Learning

Analyze the Performance of Electroactive Anticorrosion Coating of Medical Magnesium Alloy Using Deep Learning

Anticorrosive Coating of Propolis Extract for CA-50 Carbon Steel Reinforcement

Anticorrosive Coating of Propolis Extract for CA-50 Carbon Steel Reinforcement

Study of the Effect of Selective Laser Melting Parameters on the Structure and Physico-Mechanical Properties of a Blank Made of Stainless Chromium-Nickel Steel

Currently, there are a number of additive technologies that are used in various industries (laser fusion of powder materials, electron beam melting, etc.). The formation of metal structures and products by methods of additive technologies occurs by adding a new layer of material and its further melting (sintering), ensuring the adhesion of each subsequent layer with the previous one in accordance with digital model data. The advantages of using and developing additive technologies include the possibility of using a wide range of materials, obtaining finished products with complex geometries, restoring and repairing damaged structures, as well as the possibility of applying protective and anticorrosive coatings. Metal powder materials with specified physical and mechanical properties are of crucial importance in additive manufacturing. The main requirements for such powders include requirements for their shape and size. The preferred particle shape is spherical, as it provides a more compact installation in a given volume and the necessary fluidity of the material, which is due to the low resistance in the supply systems of powder materials in 3D printers. The aim of the work is to study the influence of the parameters of the SLM printing process on the structure and mechanical properties of products made of 12Cr18Ni10Ti alloy. Samples obtained by selective laser melting were subjected to pycnometric and metallographic analysis. Based on the obtained microstructure images, a digital porosity analysis of the work piece under study was performed in the Thixomet Pro software package. The microhardness and acoustic characteristics were also measured over the entire section of the work piece under study. It was revealed that with an increase in the distance from the substrate (0...112 mm) in the transverse and longitudinal sections, the tendency remains to decrease the density values and increase the volume fraction of pores. It is shown that the acoustic parameter Dc can be used to control changes in the physical and mechanical properties of stainless chromium-nickel steel blanks obtained by selective laser melting.

Microcapsulated and active additives to enhance the anti-scale properties of polymer anticorrosive coatings

Microcapsulated and active additives to enhance the anti-scale properties of polymer anticorrosive coatings

Anti-bioadhesive polyurethane coatings enhanced by salicylic acid-carboxy-betaine modified nano-silica: Stepwise antifouling mechanism

Environmentally friendly antifouling coatings have received increasing attention in the field of marine infrastructures. In this work, a carboxy-betaine salicylate surface-modified silica nanofiller (QAs-SA@SiO2 NPs) was synthesized and doped in polyurethane coatings (PU) to gain durable antifouling properties. The modified silica NPs were prepared by the covalent bond grafting method and then dispersed in PU paint to produce a kind of composite anti-fouling coating (QAs-SiO2 PU). It is noted that the QAs-SiO2 PU coating can adjust the release rate of salicylate according to environmental pH value. Once the salicylate layer was dissolved, the inner amphoteric carboxy-betaine molecules would be exposed to form a hydrated layer on QAs-SA@SiO2 NPs, thus realizing a step-by-step antifouling performance. The experimental results show that the 7 wt% addition of QAs-SA@SiO2 filler in the PU coating can reduce protein adhesion by 99.1 %, bacterial adhesion by 99.8 %, and chlorella adhesion by 95.0 %, presenting a significant mussels-repellence ability compared to the pristine PU coating. This work may provide a promising approach to designing eco-friendly and durable marine anti-fouling and anti-corrosion coatings.

Study on the corrosion behavior of laser surface remelted and laser cladding of ferritic/martensitic steels after exposure to lead-bismuth eutectic at 700 °C

This study explores two vital structural materials, T91 (Fe-9Cr) and SIMP (Fe-11Cr) steels, in the context of lead-cooled fast reactors and accelerator-driven sub-critical systems (ADS). Lead-bismuth eutectic (LBE) functions as a key coolant and spallation target material due to its impressive thermal conductivity, neutron yield, and chemical properties. Unfortunately, materials in contact with LBE are prone to severe corrosion at elevated temperatures (T>500 °C), compromising their integrity. To bolster corrosion resistance, we utilized laser remelting and laser cladding to apply FeCrAl/TiN coatings on the steel surfaces. Our study scrutinizes the corrosion behavior of steel in LBE saturated with oxygen at 700 °C and investigates the underlying causes. Following 240 h of exposure to corrosion, T91 and SIMP steels subjected to laser remelting displayed substantial oxide scale formation. Lead-bismuth atoms infiltrated the outer oxide layer (Fe3O4), diminishing adhesion between the inner and outer oxide layers, leading to the detachment of the outer oxide layer. The inner oxide layers, composed of Fe-Cr spinel, were approximately 123 μm thick for T91 steel and 77 μm for SIMP steel, underscoring SIMP steel's superior corrosion resistance. For T91 steel treated with laser cladding FeCrAl/TiN coating, a characteristic duplex oxide layer with a total thickness of around 83 μm was formed, with noticeable deposition of Pb-Bi atoms at the interface between the outer and inner oxide layers. Conversely, only a protective alumina layer safeguarded SIMP steel from LBE corrosion. This outcome emphasizes the efficacy of laser cladding FeCrAl/TiN coating in providing superior protection for SIMP steel over T91 steel. Our research significantly contributes to the development of anti-corrosion coatings for high-temperature LBE environments.

Bio-inspired Ti3C2Tx MXene composite coating for enhancing corrosion resistance of aluminum alloy in acidic environments

Aluminum alloy (Al alloy) suffers from severe corrosion in acidic solution. Two-dimensional (2D) MXene-based composite coatings show great prospects for corrosion protection on metals used in special conditions. The composite coatings still face challenges in complex functionalization and orientation control. In harsh conditions, the long-term ability and roles of MXene in corrosion protection are still not clear. Here, a bio-inspired myristic-calcium chloride-Ti3C2Tx MXene (MA + CaCl2 + MXene) composite coating is successfully prepared on aluminum alloy (Al alloy) by electrodeposition process. Electrochemical tests, surface morphology, and chemical composition are analyzed to investigate the corrosion resistance and protection mechanism of the MXene coating in acidic solution (0.5 M H2SO4 + 2 ppm HF). As a result, the incorporation of MXene can significantly reduce corrosion current density (7.498 × 10-8 A/cm2) by ∼ 5 orders of magnitude and impedance modulus at 0.01 Hz (|Z|0.01 Hz) value of the composite coating is 196.8 Ω·cm2, which is over 4 times higher than that of bare Al alloy (40.74 Ω·cm2) after immersion test for 72 h. Furthermore, the in-situ corrosion test confirms the enhanced corrosion resistance of the MA + CaCl2 + MXene composite coating. The MXene can increase coating thickness to 23.6 ± 0.4 μm, reduce porosity to (5.845 ± 1) × 10-5, decrease the diffusion coefficients of H+ to (1.587 ± 0.3) × 10-9 cm2/s, and enhance the adhesion of the coating to the substrate (the delamination time exceeds 5 h), thus providing improved anti-corrosion ability. This strategy opens up new prospects for construction of 2D MXene-based anti-corrosion coatings.

The novel damage-reporting and self-healing coatings prepared by electrospinning technology based on AIE agents and photothermal shape memory polymer

The self-healing coatings for metals aroused researchers' interest due to their spontaneous repair of coating damage. In this study, intelligent damage-reporting and self-healing anti-corrosion coatings were developed using electrospun fiber as the core functional materials. The fibers exhibited core–shell structures, with the core materials being the solutions of the composite fluorescence probe RTPE. The shell materials consisted of the photothermal shape memory polymer, namely, phosphotungstic acid modified polyaniline-polyurethane composite polymer. Rhodamine Tetraphenylethylene (RTPE) demonstrated water-triggered aggregation-induced emission (AIE) effects and also exhibited fluorescence response to corrosive factors such as hydrogen ions and iron ions at the damaged area of the coatings. Under the trigger of the infrared laser, the modified polyaniline converted light energy into heat, causing the softening of epoxy and the shape memory effect of polyurethane. These processes facilitated the closure and repair of the damage, thus restoring their anti-corrosion functionality. Phosphotungstic acid played a role in enhancing the photothermal efficiency. The self-healing mechanism reinforced the corrosion resistance of the coatings. The self-indicating feature for damaged areas provided guidance for artificial repair in regions that did not self-heal satisfactorily. The synergistic and intelligent functionalities of the prepared coatings foreshadowed the significant potential applications in marine and aerospace corrosion protection fields.

Fabrication and film-forming mechanism of PCTFE films with exceptional water-vapor barrier and mechanical properties via solvent-assisted method

Polychlorotrifluoroethylene (PCTFE) has the outstanding water-vapor barrier performances among thermoplastics, and is with excellent transparency, high cryogenic toughness, and ultralow dielectric constant/loss. It plays an important role in high-performance packaging, electric circuit constructions, anti-corrosion coatings, cryogenic sealing, and so forth. Nevertheless, due to its borderline thermal stability and sensitivity to shearing effect, the melt-processing of PCTFE is rather difficult. Herein, a solvent-assisted method, which contained fabrication, coating, drying, and sintering of PCTFE suspension, was proposed for the fabrication of PCTFE films. The influence of processing parameters, including particle shape, drying temperature, and sintering time on the film-forming process was investigated. The as-prepared PCTFE films exhibited exceptional mechanical properties, with a tensile strength and failure strain of ∼42 MPa and ∼108 %, respectively. The water vapor transmission rate, light transmittance, and haze reached ∼0.02 g/(m2·24 h), ∼91 %, and ∼3 %, respectively. Finally, the potential film-forming mechanism was explained by the densification of PCTFE particles via capillary force, neck formation and particles coalescence driven by surface tension and viscous flow, and co-crystallization across the initial particle interfaces. In summary, the solvent-assisted method opened a new pathway for the processing of PCTFE films and is conducive to broadening their application fields.

One-step preparation of color-tuned surface coatings on magnesium alloy with corrosion resistance

Nowadays, few works have been undertaken to explore the anti-corrosion coatings with tunable surface colors. In order to further expand the industrial application of magnesium alloy, a facile one-step hydrothermal method was applied to AZ91D magnesium alloy to obtain anti-corrosion coatings with diversified colors. The formation mechanism was discussed, and the corrosion resistance of the coating was assessed by electrochemical tests, immersion tests, and salt spray tests. The results show that different coating colors such as yellow, cyan, blue and red can be obtained by varying the type and concentration of reagents. The adhesion of the coating to the magnesium alloy substrate was great, and the corrosion current density of the sample with the best anti-corrosion effect was reduced by three orders of magnitude. This method has practical significance in promoting the development of surface coloring and industrial applications of magnesium alloys.

Concentration dependences of the coefficients of acid diffusion into epoxy binders of anticorrosion coatings

Concentration dependences of the coefficients of acid diffusion into epoxy binders of anticorrosion coatings

Evolution of electrochemical impedance spectra of adaptive polymer anticorrosive coatings modified with carbon nanotubes exposed to corrosive environment

Evolution of electrochemical impedance spectra of adaptive polymer anticorrosive coatings modified with carbon nanotubes exposed to corrosive environment

Self-healing coating with the ability to mark damaged locations, based on electrospun photothermal fibers and AIE agents

The anti-corrosion coatings based on core-sheath fibers prepared by electrospinning methods are developed for the indication and repair of large-scale damage to coatings. The cores are the composite fluorescent agents composed of AIE-gens and CHEF-gens, which exhibit strong fluorescence characteristics sensitive to corrosion due to the CHEF and FRET effects. The composite fluorescent agents provided information about the location of damages when the coatings, with the fibers as the core materials, are damaged. The sheaths are photothermal materials, composed of photothermal responsive acid doped polyaniline and shape memory polyurethane. The photothermal properties of acid doped polyaniline, under the irradiation of an infrared laser, contributes to heating in the damaged areas. The softened and activated polyurethane simultaneously lead to interpenetration and entanglement of molecular chains at the closed damage sites, resulting in complete repair of the damaged coatings.

Efficiency of Anti-Corrosion Protective Coatings Based on Graphene Oxides Functionalised with Green Inhibitors

Mild steel (MS) is commonly used for infrastructure and machinery due to its various engineering properties and benefits, but they are highly prone to corrosion. For decades, organic polymeric coatings are widely applied to protect metallic systems against corrosion. Besides the physical barrier, the organic coatings have been manipulated by adding anti-corrosion pigments or corrosion inhibitors, such as red-lead or chromate to enhance protection. However, these conventional anticorrosive pigments have been substituted because of their toxicity and environmental problems. Recent studies have been consequently conducted to develop environmentally safe and green alternatives obtained from natural products.In the framework of this study, a novel green hybrid pigment nano-pigment based on graphene oxide (GO) and an organic natural inhibitor was prepared and included in a Polyvinyl Butyral (PVB) coating. The protective properties of PVB coatings without and with the addition of GO and f-GO on steel in 3.5wt% NaCl solution were studied by electrochemical methods.The new pigment functionalised GO (f-GO) is not only able to be an outstanding barrier, but it can also store a considerable amount of corrosion inhibitors and release them, when necessary, on the protective coating system. GO was functionalised with the green inhibitor in aqueous phase and the compound obtained was characterised by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermo gravimetric analysis (TGA), ultraviolet-visible spectroscopy (UV-Vis) and atomic force microscopy (AFM).FT-IR and UV-Vis spectroscopy results indicated that the organic compound effectively reduced GO into f-GO and PVB/f-GO composite coatings showed 100 times higher anticorrosion resistance than PVB/GO and neat PVB. Figure 1

Thin Sputtered Titanium Nitride Layers for Corrosion Protection of 316L Stainless Steel Under PEM Water Electrolyzer Anode-like Conditions

Proton exchange membrane water electrolyzers (PEMWE) electrochemically split the water molecule in order to produce high-purity oxygen (at the anode) and hydrogen (at the cathode). When coupled to a renewable energy source (such as wind or sun), green hydrogen can be synthesized, which may contribute to a massive reduction in carbon dioxide emissions in the so-called “hard-to-abate” industrial sectors, like steel and cement manufacturing.Yet, the elevated capital expenditures (capex) deriving from the use of expensive corrosion-resistant materials undermine the economic competitiveness of the PEMWE technology compared to the main hydrogen production processes, like steam reforming. To date, on the PEMWE anode side, metallic bipolar plates (BPP) and porous transport layers (PTL), are essentially made of titanium coated with precious metal layers (platinum, gold) so as to withstand the corrosive and oxidizing environment. Consequently, BPP and PTL account for more than 60% of the capex of the PEMWE stack [1,2]. Without corrosion protection, the harsh operating anodic conditions may lead to performance-killing release of cationic elements from the BPP and PTL into the catalyst layer and the polymer electrolyte [3]. It may also cause the growth of resistive oxide layers at the BPP and PTL surfaces and the development of undesired interfacial contact resistance (ICR).This contribution will focus on the corrosion protection of the anode side of BPP and will first briefly review the most recent investigations driven by capex reduction, notably based on the replacement of titanium by stainless steels and the application of novel, more cost-effective anti-corrosion coatings [3].In a second part, results on the corrosion protection of 316L stainless steel by thin layers of titanium nitride prepared by DC magnetron sputtering will be presented. The thin TiN coatings were deposited on glass, silicon and 316L stainless steel substrates using a titanium target reacting with nitrogen gas. The crystalline phase, the nanostructure and the composition of the thin films were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X-ray reflectivity, energy dispersive X-ray spectroscopy and electron energy loss spectroscopy. The corrosion resistance of the TiN-coated stainless steel was evaluated ex situ using open-circuit potential monitoring and electrochemical impedance spectroscopy in dilute H2SO4 solution in a three-electrode electrochemical cell. The interfacial contact resistance was assessed before and after corrosion testing. The protective properties of titanium nitride coatings on 316L under PEMWE anode-like conditions will be discussed.Acknowledgements The authors gratefully acknowledge the financial support of the French National Research Agency (agreement ANR-22-PEHY-0009 under the France 2030 program as well as agreement ANR-22-CE93-0008-01).