Corrosion Resistance Performance Research Articles

A Microporous Channel Copper Immersion Layer Promotes the Rapid Ni-P Electroless Plating Process on Aluminum Alloys at Medium and Low Temperatures

Abstract Electroless plating is a commonly used method to enhance the corrosion resistance, wear resistance, and decorative performance of aluminum alloys. However, in electroless plating processes, it is customary to maintain the solution temperature at levels exceeding 85°C, a critical condition that ensures a sufficiently rapid deposition rate and thereby fosters the formation of high-performance coatings. Conventional immersion pretreatments with zinc and palladium result in lower deposition rates at low temperatures. This study shows that a copper immersion layer with microporous channels can facilitate the electroless plating process for aluminum alloys at lower temperatures. Through a redox reaction in a Cu2+-containing solution at 70°C, a copper immersion layer with a microporous structure could be created on an aluminum alloy. The microporous channels between the copper immersion layer and the aluminum alloy create electrochemical corrosion cells in the plating solution, accelerating the electroless plating process. The Ni-P coating obtained after pretreatment by copper immersion has a higher hardness (578 HV) and a lower corrosion current density (0.55 μA/cm2). This work provides a practical method to rapidly fabricate high-performance Ni-P coatings at intermediate temperatures (70-75°C).

Research on the Performance of Steel Strand-Reinforced Reactive Powder Concrete with Mixed Steel Fibers and Basalt Fibers under the Salt Dry–Wet Erosion

In this study, the properties of steel strand-reinforced reactive powder concrete (RPC) with mixed steel fibers and basalt fibers were investigated. The volume ratios of steel fibers and basalt fibers ranged from 0% to 2%. The reinforcement ratio of steel strands was 1%. The flexural strength and toughness were measured. Moreover, the impact toughness was determined. The studies were carried out under an erosion environment with chlorides and sulfates. The electrical resistance and the ultrasonic velocity were obtained to assess the salt corrosion resistance performance of steel strand-reinforced RPC. The results show that the addition of basalt fibers and steel fibers can improve the mechanical strength, ultrasonic velocity, flexural toughness, and impact toughness and decrease the performance degradation of the steel strand-reinforced RPC under the conditions of dry–wet alternations of NaCl and Na2SO4 solutions. Basalt fibers and steel fibers can improve the steel strand-reinforced RPC’s flexural strength by rates of up to 13.1% and 28.7%, respectively. Moreover, the corresponding compressive strength increases by 10.3% and 18.3%. The flexural strength decreases by 11.2~33.6% and 7.3~22.7% after exposure to the NaCl and Na2SO4 dry–wet alternations. Meanwhile, the corresponding compressive strength decreases by 22.1~38.9% and 14.6~41.3%. The electrical resistance increases with the addition of basalt fibers and decreases with the increasing dosages of steel fibers. The steel strand-reinforced RPC with the assembly units of 1% steel fibers and 1% basalt fibers shows the optimal mechanical properties and salt resistance considering its wet–dry alternation performance. The properties of steel strand-reinforced RPC decrease more rapidly after undergoing NaCl erosion than Na2SO4 erosion.

Cold Spray Technology and Its Application in the Manufacturing of Metal Matrix Composite Materials with Carbon-Based Reinforcements

Cold spray technology, as an emerging surface engineering technique, effectively prepares hard coatings by high-speed projection of powder materials onto substrates at relatively low temperatures. The principal advantage of this technology lies in its ability to rapidly deposit coatings without significantly altering the properties of the substrate or powder materials. Carbon-based materials, especially carbides and diamond, etc., are renowned for their exceptional hardness and thermal stability, which make them indispensable in industrial applications requiring materials with high wear resistance and durability at elevated temperatures. This review elucidates the fundamental principles of cold spray technology, the key components of the equipment, and the properties and applications of hard coatings. The equipment involved primarily includes spray guns, powder feeders, and gas heaters, while the properties of the coatings, such as mechanical strength, corrosion resistance, and tribological performance, are discussed in detail. Moreover, the application of this technology in preparing metal matrix composite (MMC) materials with carbon-based reinforcements, including tungsten carbide, boron carbide, titanium carbide, and diamond, are particularly emphasized, showcasing its potential to enhance the performance of tools and components. Finally, this article outlines the challenges and prospects faced by cold spray technology, highlighting the importance of material innovation and process optimization. This review provides researchers in the fields of materials science and engineering with a comprehensive perspective on the application of cold spray technology in MMC materials with carbon-based reinforcements to drive significant improvements in coating performance and broaden the scope of its industrial applications.

The corrosion resistance and anti-bacterial performance of polyelectrolyte-embedded Ca-P coating loaded with ciprofloxacin on magnesium alloy

Polyacrylic acid (PAA) is utilized as the template for the hydrothermal fabrication of Ca-P coatings on biodegradable magnesium (Mg) alloys, and ciprofloxacin (CIP) is also adopted for the coating's anti-bacterial performance. The coating's composition and structure are characterized. The anti-bacterial performance of the coating is evaluated using plate counting method against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The corrosion rates of different samples are measured by electrochemical polarization, electrochemical impedance spectroscopy (EIS), and hydrogen evolution (HE) experiments. The long-term release behavior of the loaded antibiotics is analyzed through UV–vis. The results show that the obtained coating would display corrosion protection, anti-bacterial effect, and acceptable adhesive force, verifying that this drug-loaded coating effectively overcomes the limitations of Mg alloys in the biological environment. The biocompatibility of the coating is also characterized using the CCK-8 method. Finally, the role of the PAA in the structural transformation of the coating is explained based on the molecular dynamics (MD) simulation and this method seems to open a new pathway for understanding the reconstructing effect of the templates inside a hydrothermally synthesized coating.

Enhancing the protective performance of anti-impact, corrosion resistant and flame retardant polyurea coatings using bio-based supramolecular decorated montmorillonite

Developing bio-based nano-additives for enhancing mechanical strength, corrosion resistance, and flame retardancy in polyurea (PUA) coatings at low loading levels is crucial for human well-being and environmental preservation. In this study, montmorillonite (MMT) was first exfoliated by ball milling with the aid of chitosan, and then further co-assembled with phytic acid and urea to form a nanohybrid (CPN@MMT). The resulting CPN@MMT nanohybrid exhibited good compatibility and dispersibility within matrix and endowed PUA composites with improved anti-impact, corrosion resistant and flame retardant properties. Remarkably, the addition of CPN@MMT improved the mechanical and impact protection properties of PUA coatings. Electrochemical and salt spray tests confirmed that the excellent anti-corrosion performance of PUA composite coating stemmed from the dispersed nano-sheets forming a protective nano-barrier. CPN@MMT in the PUA matrix formed a compact char layer, reducing heat release and smoke by inhibiting heat diffusion and volatile gas evaporation, as evidenced by cone calorimeter and TG-FTIR tests. The enhanced fire safety was primarily attributed to the physical barrier, catalytic charring and dilution effect of CPN@MMT. Hence, a green and feasible method was developed to create bio-based nano-additive in PUA coatings with anti-impact, corrosion resistant and flame retardant performance.

Effect and mechanism of bias voltage on microstructure and corrosion resistance of CrxNy coatings in proton-exchange membrane fuel cells

The key factor limiting the long-term commercial application of CrxNy coatings in the PEMFC is that these coatings easily grow into coarse columnar crystals with subsequent microcracks and pinholes, leading to a sharp decrease in corrosion resistance performance. In this view, a series of different substrate bias voltages were applied to deal with this problem. The results demonstrated that with applying a −120 V bias voltage on the substrate, the adhesion strength is double that of the CrxNy coating without bias voltage. In addition, the −120V-CrxNy sample exhibits the lowest corrosion current density of 0.65 μA/cm2 and a minimum ICR value of 5.87 mΩ cm2, thus highly meeting the U.S. DOE 2025 targets. Moreover, the CrxNy coatings subjected to bias voltages ranging from −100 V to −140 V exhibit excellent durability and stability, with current densities that are 1-2 orders of magnitude lower compared to the 0V-CrxNy coatings. Therefore, this work provides a novel approach to control the growth of columnar crystals in CrxNy coatings for future PEMFC manufacturing processes, and has important reference value for the regulation of columnar crystals in other coatings such as TiN, NbN, AlN, etc.

A corrosion model for CZ cladding based on in-pile irradiation data

Corrosion resistance is the critical in-pile property for developing new Zircaloy cladding. As a new Zircaloy developed by China General Nuclear Power Corporation, CZ will be used as fuel rod cladding. This study is devoted to investigating the corrosion behavior of CZ. A two-stage Arrhenius equation is proposed to model the corrosion rate. A total of 1,510 measurement data points taken from 151 fuel rods irradiated for 1–4 cycles were used to develop the corrosion model. The burnup of these fuel rods ranges from 13.7 MWd/kgU to 55.9 MWd/kgU. The mean value and standard deviation of P−M (predicted value minus measured value) are 0.54 and 3.65 microns, respectively, and the mean value and standard deviation of P/M (predicted value divided by measured value) are 1.09 and 0.34 microns, respectively. P−M and P/M increase with the local burnup. When the burnup is greater than 40 MWd/kgU, the mean values of P−M and P/M are 6.2 and 1.20 microns, respectively; on the other hand, the prediction of the proposed model is more conservative in high burnup. In the typical case in which the average burnup reaches 57 MWd/kgU, the oxide thickness of CZ cladding is much less than 30 microns, whereas the oxide thickness of Zr-4 cladding is approximately 80 microns, and this manifests that CZ cladding possesses excellent performance in corrosion resistance.

Modeling of particle erosion of high-pressure turbine based on dynamic mesh method

In this work, we investigate erosion characteristics of a high-pressure turbine by using Oka erosion model coupled with the dynamic mesh method, which allows for the dynamic change of blade profile. The variation of blade profile, material removal and performance degradation during erosion are quantified for the original blade, and the results are compared with those of an optimized blade previously obtained through multi-objective optimization of aerodynamic and erosion resistance performances. It is found that compared with the original blade, the optimized blade is of higher efficiency and lower erosion, suggesting that the previous multi-objective optimization, albeit ignoring the dynamic change of blade profile, still works for the dynamic erosion process. For either blade, the efficiency decreases slowly at first and drops sharply after a period of erosion, because as the erosion proceeds, the regions occupied by the vortex rapidly expand, leading to the blockage of blade passage. The transient erosion characteristics and particle trajectories indicate that the erosion is initially located near the middle and rear of blade on pressure side and the leading edge on suction side; as the erosion progresses, the erosion mainly occurs near the leading edge on pressure side but almost disappears on suction side.

The role of Zinc Molybdate in the anticorrosion and antibacterial characteristics of sustainable polyurethane coating derived from epoxidized soybean oil

Vegetable oils are important renewable sources that have been used as alternative feedstocks to petroleum for the synthesis of polyols. Polyols are compounds that contain multiple hydroxyl groups in a molecule and are a major component of polyurethanes. One of the oldest problems that many industries face today is corrosion. Polyurethane coatings reduce the rate of corrosion reactions but are not completely impermeable to corrosive agents. Nanoparticles, due to their high surface area and small particle size, can improve the performance of polyurethane coatings and block the penetration of corrosive agents. This research aims to prepare polyurethane coatings using soybean oil-based polyol and investigate the corrosion resistance performance of polyurethane coatings by adding Zinc Molybdate (ZnMoO4) nanoparticles. To achieve this goal, a polyol based on soybean oil was synthesized through the ring-opening reaction of Epoxidized soybean oil. Then, polyurethane coatings with 0.5, 1, 1.5, and 2 wt% of ZnMoO4 nanoparticles were prepared. Characterization of the polyurethane coatings was performed using FTIR, HNMR, and FESEM. The mechanical properties were also examined. Finally, the corrosion resistance activity of these nanocomposites was evaluated using electrochemical impedance spectroscopy and potentiodynamic polarization tests. The results showed that adding 0.5%w/w of ZnMoO4 nanoparticles can improve the performance of polyurethane coatings against corrosion, as the nanoparticles were uniformly dispersed on the surface of the coating and blocked the penetration of corrosive agents. Therefore, 0.5 wt% ZnMoO4 nanoparticles can be considered as the optimal amount in this experiment. Moreover, the modified coating with ZnMoO4 nanoparticles can effectively act against both gram (+) and gram (-) bacteria.

Ceramic Matrix Composites: Classifications, Manufacturing, Properties, and Applications

Ceramic matrix composites (CMCs) are a significant advancement in materials science and engineering because they combine the remarkable characteristics of ceramics with the strength and toughness of fibers. With their unique properties, which offer better performance and endurance in severe settings, these advanced composites have attracted significant attention in various industries. At the same time, lightweight ceramic matrix composites (LCMCs) provide an appealing alternative for a wide range of industries that require materials with excellent qualities such as high-temperature stability, low density, corrosion resistance, and excellent mechanical performance. CMC uses will expand as production techniques and material research improve, revolutionizing aerospace, automotive, and other industries. The effectiveness of CMCs primarily relies on the composition of their constituent elements and the methods employed in their manufacturing. Therefore, it is crucial to explore the functional properties of various global ceramic matrix reinforcements, their classifications, and the manufacturing techniques used in CMC fabrication. This study aims to overview a diverse range of CMCs reinforced with primary fibers, including their classifications, manufacturing techniques, functional properties, significant applications, and global market size.

Data-Driven Approach for Selecting Mechanical Rebar Couplers Based on the Shape and Structural Characteristics of Reinforcing Bars for Sustainable Built Environment

Lap splices are the most commonly used method worldwide because they do not require specific equipment or skilled workers. However, lap splices incur high construction costs because of the long splice lengths required for large-diameter rebars in megastructures, as well as issues pertaining to material supply, labor costs, constructability, and project duration. Additionally, approximately 15% more rebar is required because of the overlap. Energy saving for a sustainable built environment is possible if the disadvantage of lap splices, which generate high CO2 emissions due to the excessive use of rebar, are resolved. Hence, mechanical rebar couplers (MRCs) have been developed. However, despite their advantages, they have not been widely applied in construction sites owing to concerns regarding safety, quality, and constructability. This is because data on MRC, including maintenance, and environmental impact, are not organized, making it difficult to select a coupler suitable for the environment during the construction stage. Therefore, a data-driven approach for selecting MRCs based on the reinforcing bar shape and structural characteristics is proposed in this study. The T-epoxy filled sleeve coupler was found to be the best in terms of seismic performance, durability, corrosion resistance, and long-term performance. In addition, using a data-driven MRC selection algorithm using the T-threaded coupler for one rebar over two floors resulted in 56% more efficient labor productivity, 15% shorter assembly time, 17% lower costs, and 26% lower CO2 emission. Using a developed algorithm, the appropriate MRC can easily and rapidly be selected for frequent design changes.

The development of high‐strength, anticorrosive, and strongly adhesive polyaspartate polyurea coating suitable for pipeline spray repairs

AbstractThis study synthesized polydimethylsiloxane (PDMS)‐modified polyaspartate polyurea (PPPU) with different ratios, considering the practical performance requirements of underground water supply pipeline spray repair materials. The successful synthesis of PPPU was confirmed using Fourier transform infrared spectrometer (FTIR) spectroscopy. The influence of the ratio of the two components and the content of ‐aminopropyl terminated polydimethylsiloxane (APT‐PDMS) on the drying time and tensile performance of PPPU coatings was evaluated. Based on this evaluation, a superior ratio for PPPU coatings was proposed. Subsequently, the bonding performance, hydrophobicity, and corrosion resistance of PPPU coatings at the superior ratio were tested. The results indicate that as the mass ratio of polyaspartic acid ester to hexamethylene diisocyanate trimer increases, both the drying time and tensile strength of the coating decrease. The addition of APT‐PDMS results in a decrease in the tensile strength of PPPU, but an increase in its elongation at break. The peak value of elongation at break is achieved when the APT‐PDMS content is 5%, making the PPPU2‐1‐5 coating the superior ratio for spray application on water supply pipelines. Through experiments, it was determined that the bonding strength of the PPPU2‐1‐5 coating with cement mortar under dry and humid conditions, static water contact angle (93.4°), and corrosion resistance performance are superior to those of the unmodified polyurea coating, demonstrating its application advantages. The conclusions drawn in this study provide a theoretical foundation for the practical engineering application of PPPU.

Study on the Corrosion Resistance Of Thermal Sprayed Aerospace Coatings Under The Action Of High Current Pulsed Electron Beam

Aluminum-based amorphous alloys have excellent mechanical properties and corrosion resistance and are currently used in the form of coating materials for the protection of aircraft surfaces. In this study, AlCoCe alloy and powder are prepared, and then AlCoCe alloy coating is prepared on Q235 substrate by supersonic flame thermal spraying technology, and finally, the surface remelting modification treatment is carried out on the coating by current pulsed electron beam, and the transformation behavior of microstructure of the coating and the change of the corrosion resistance in this process are analyzed by structural characterization and corrosion experiment, to make clear the relationship between the structure of the coating and its corrosion resistance performance. After 15 current pulsed electron beam pulses, the coating surface formed a layer of dense and homogeneous composition of the amorphous structure of the treatment layer, when the number of pulses is higher, due to the heat of the substrate leads to a decrease in the cooling rate, which in turn will lead to the emergence of a crystalline structure of the surface treatment layer.

Investigation of segregation behaviour in 2060 aluminium-lithium alloy during twin-roll casting

The utilization of the twin-roll casting process to fabricate aluminium (Al) - lithium (Li) alloys is regarded as an efficient and energy-saving strategy to meet the aerospace industry’s demands for reducing processing steps, cost-effectiveness, and corrosion resistance. This study successfully achieved the preparation of Al-Li alloy twin-roll cast slabs across various processing ranges to investigate the corrosion resistance differences in different processing conditions. Remarkable macro segregation phenomena were observed in the fabrication under high twin-roll casting speeds for TRC-3. By combining temperature and flow rate calculations, we comprehensively analysed the results of this segregation mechanism. The segregation is inherited into the final T6 state microstructure, exacerbating the precipitation of the T1 phases and deteriorating the ultimate corrosion resistance performance. We delved into a profound discussion regarding the mechanistic impact of segregation on corrosion behaviour. Ultimately, this study postulates a process parameter range for twin-roll casting of Al-Li alloys, aimed at attaining minimal segregation and maximal corrosion resistance.

Studying how changes in the structure caused by hydrogen bonding affect the corrosion resistance of polybenzoxazine-based coatings using molecular dynamics simulations

Polybenzoxazine (PBz) based coatings were prepared using designed PBz monomers for corrosion protection. The structure and properties of poly(MPM) and poly(POPM) coatings deriving from PBz monomer with methyl group and phenoxy group, respectively, were fully investigated by Fourier transform infrared spectroscopy, water contact angle measurements and electrochemical impedance spectroscopy. For the two crosslinking coating systems, the poly(POPM) coating, with a lower intermolecular hydrogen bonding ratio of 9.7 %, exhibited better hydrophobicity, stability, and corrosion resistance. This is evidenced by a water contact angle (WCA) exceeding 94° (90° for poly(MPM) system) and a charge-transfer resistance surpassing 1 GΩ cm2 (1 MΩ cm2 for poly(MPM) system) even after 30 days of immersion in a 3.5 wt% NaCl solution. The distinct performance in corrosion resistance performance between the two systems can be attributed to structural changes arising from hydrogen bonding, which were extensively investigated through solubility parameters calculation and molecular dynamics simulations in this study. The results show that the prevalence of intra‑hydrogen bonding in the poly(POPM) coating lead to a more compact structure and enhanced hydrophobicity against water, thereby enhancing the barrier ability of PBz based coatings against the penetration of corrosive substances.

Higher laser power improves strength but reduces corrosion resistance of Mg WE43 processed by powder bed fusion

Powder bed fusion – laser beam (PBF-LB) of Mg alloys provides new possibilities for the production of complex structures with optimized designs, both for weight reduction in aerospace applications, as well as for patient-specific implants in orthopedic applications. However, even though numerous studies have been carried out on the topic, the influence of the individual PBF-LB process parameters on the microstructure and resulting material properties of Mg alloys remains ambiguous. Thus, this study aims to investigate the influence of laser power on the surface roughness, microstructure and resulting key material properties, namely corrosion resistance and mechanical performance. Samples were produced by PBF-LB from gas atomized Mg-4%Y-3%Nd-0.5%Zr (WE43) alloy powder, using three different laser powers: 60 W, 80 W, and 90 W. Contrary to expectation, the 90 W samples exhibited the highest degradation rate, while 60 W samples had the lowest, despite the latter having highest surface roughness and large internal pores. The higher degradation rate for the 90 W samples was instead found to stem from the near-surface microstructure. The higher energy input and subsequently reduced grain size, resulted in an increased amount of second phase precipitates than for the 60 W samples, thereby increasing the tendency for pitting via microgalvanic corrosion. For the tensile strength and elongation at break, the opposite trend was observed. Here, a reduction in grain size and an increase in precipitates for the 90 W samples were found to be beneficial. In conclusion, a definite influence of laser power on the formation of microstructure was observed, ultimately impacting the resulting corrosion and tensile properties of WE43. Future work should investigate the influence of other PBF-LB process parameters, with the aim of establishing an optimum balance between corrosion resistance and mechanical properties.

Corrosion resistance of Nb and NbTi alloy predicted by hydrogen evolution reaction models modified with Langmuir isotherm adsorption theory

Langmuir isotherm adsorption theory is involved in the conventional model to predict the corrosion resistance of Nb and Nb alloys. It is illustrated that the anti-corrosion properties of Nb are dependent on the crystal plane, pH values and solution temperature. Nb(110) plane with the lowest Esurf/ρ and the highest Eesc present the slower dissolution of Nb atoms, and then exhibits the best anti-corrosion performance. Alloying with Cr, Cu, Mo, Ti and Ta destroys the stability of Nb(110) plane and thus degrades the corrosion resistance performances. Moreover, the anti-corrosion performance is improved with increasing pH values because of the decreasing coverage of H+ ions. The escape rate of Nb atoms will be accelerated at the elevating temperature, and thus the anti-corrosion performance be degraded. Therefore, an appropriate design of coating texture and solution environment could improve the anti-corrosion performances of bipolar plates.

High-temperature corrosion-resistant alloy for waste-to-energy plants: Alloy designing, fabrication, and possible corrosion-resistance mechanism

This study designed a novel high-temperature corrosion-resistant alloy through thermodynamic equilibrium computations. The strength was determined by the integration of precipitation-strengthening species of nickel boride and tungsten solid solution strengthening, while high-temperature corrosion-resistant property was realized through optimized compositional design. Phase stability was enabled by the presence of a face-centered cubic structure. The alloy was fabricated and its corrosion-resistance performance was experimentally compared with other commercially available nickel- and iron-based alloys under simulated municipal solid waste combustion. The designed alloy with a composition of Ni-5B-6W-28Cr-13Al showed a low corrosion rate of ∼72 % < 13CrMo4-5TS and 1.08 % > Inconel 625. Economic analysis showed that Ni-5B-6W-28Cr-13Al has a cost-effectiveness ratio of 1:1.57 with respect to Inconel 625 and 1:0.09 with respect to 13CrMo4-5TS. Corrosion-resistance mechanism was explored using scanning electron microscopy coupled with energy dispersive spectroscopy, x-ray diffractometer, and DFT computations. The corrosion resistance occurred through the formation of a uniform tungsten-chromium-oxide film which inhibits inward diffusion of corrosive chlorine species. These findings provide insights into the development of alloys for high-temperature technologies.

Enhanced marine biofouling and corrosion resistance through springtails-inspired papillate-like micropillar arrays surface modified by antimicrobial peptide

Marine biological fouling has a serious impact on artificial facilities, and traditional antifouling coatings are not beneficial to green development, which lead to the urgent to develop green strategies that can effectively prevent fouling. In this study, an innovative confluence of physical and biological approaches was employed to mitigate the harm caused by biofouling on a material substrate. Firstly, a hierarchical microstructured morphology was prepared on an aluminum surface by reactive ion etching and characterised. The antibacterial peptide, A-2S, was surface modified with dopamine as a coupling agent to produce a physico-biological synergistic antifouling surface. X-ray photoelectron spectroscopy, fourier transform infrared spectroscopy, and electrochemical experiments were then used to analyse the binding effect and corrosion resistance performance. A-2S was successfully modified on the sample surface and exhibited good corrosion resistance with a corrosion inhibition efficiency of 86.57 %. Compared to a bare aluminum plate, the microstructure surface has a certain inhibitory effect on fouling organisms, and the antifouling performance decreases over time. In contrast, the antimicrobial peptide synergistic surfaces demonstrated superior durable antifouling performance. Compared with the 50 % of the antifouling performance on the microstructure surface, the synergistic surface has a unique contact point effect of the microstructure and excellent antibacterial and bactericidal properties of antimicrobial peptides, resulting in a surface antifouling performance of over 80 %. The synergistic modification method enhanced the corrosion resistance of the material and reduced the adhesion of fouling organisms, mitigating the harm caused by biofouling on the marine equipment substrate.

In Situ Synthesis of an Epoxy Resin Microwave Absorption Coating with Anti-Ultraviolet Aging Effects

A nanoparticle-anchored three-dimensional microsphere flower-structured layered double hydroxide (LDH) material with Fe3O4 particles was successfully prepared using simple hydrothermal and hot solvent methods. Micro-nanostructured Fe3O4@LDHs (SLF) composites balance microwave absorption, corrosion protection, and UV aging resistance. The minimum reflection loss value of SLF is −35.75 dB at 14.16 GHz, when the absorber thickness is 8 mm, and the absorption bandwidth at this frequency is up to 2.56 GHz for RL values less than −10 dB, while the LL is only 1 GHz. The SLF /EP coating has not only excellent microwave absorption performance but also excellent corrosion and UV aging resistance performance. The coating still has some anti-corrosion effect after 10 d of immersion. This work is intended as a reference for the development of new coatings with excellent microwave absorption properties as well as corrosion and UV aging resistance for wind turbine tower barrels (seaside wind power generation equipment) surfaces.