Corrosion Resistance Performance Research Articles

The influence of ultrasonic vibration on the microstructure and properties of laser-cladded Fe-Ni-Ti composite coatings

To enhance the service life of brake discs for rail transit vehicles, an experimental platform for ultrasonic-assisted laser cladding was established. Single-layer and multi-layer overlapping Fe-Ni-Ti coatings were prepared on the surface of 316 L steel with and without ultrasonic assistance. The study investigated the influence of ultrasonic vibration on the microstructure and residual stress of composite coatings, and conducted tests on hardness, frictional wear, and corrosion resistance of the coatings. Results showed that ultrasonic vibration can refine grain structures.Under ultrasonic assistance, residual tensile and compressive stresses of the multi-layer cladding decreased by 12 % and 13 %, respectively. Under ultrasonic assistance, the average microhardness of single-pass samples increased to 515 HV, while the average microhardness of multi-pass overlapping samples increased to 460 HV. After adding ultrasonic vibration, the wear rate of single-layer samples decreased by 18.1 %, and that of multi-layer samples decreased by 12.9 %. Electrochemical impedance spectroscopy shows that under the action of ultrasound, the composite coating has better corrosion resistance performance.

Investigating the Corrosion Inhibition Performance of a Novel Coconut Oil-Based Poly(urethane-urea) Hybrid Coating on Carbon Steel in 3.5% NaCl Solution

Polyurethane has been used for years as an anti-corrosion coating due to its intrinsic hydrophobic properties. However, its hydrophobicity is not enough to inhibit the permeation of corrosive agents; thus, incorporating it with polyurea would further enhance its hydrophobic properties. In this study, coconut oil, a saturated, low molecular weight vegetable oil, was employed as an eco-friendly precursor for synthesizing a novel poly(urethane-urea)- based hybrid coating. The synthesis process involved the utilization of a coconut oil-based polyol blend, triethanolamine (TEA) as an amine source, and hexamethylene diisocyanate (HDI). The resulting hybrid coating on carbon steel demonstrated remarkable anticorrosion performance in a 3.5 wt. % NaCl solution, owing to the intrinsic hydrophobic characteristics of coconut oil and polyurea. Significant corrosion rate reduction was observed with increasing amine content, accompanied by an enhancement in mechanical properties. Notably, an amine loading of 4% consistently exhibited superior corrosion resistance and mechanical performance in the hybrid coating. Chemical structural analysis revealed a hydrogen-bonding network in polyurea coatings, reducing porosity, enhancing barrier properties, and improving mechanical characteristics, highlighting its potential for sustainable corrosion protection.

Synergizing empirical and AI methods to examine nano-silica's microscale contribution to epoxy coating corrosion resistance

Epoxy-nanomaterials offer a promising solution to combat corrosion threatening civil infrastructure. To examine the impact of nano silica on corrosion resistance, varying amounts of nano silica, ranging from 0.0 to 3 wt%, were introduced into the epoxy matrix. Mechanical properties were studied through studying the dog-bone tensile strength and tribological aspects were assessed through mass loss abrasion tests. Corrosion resistance performance was studied using electrochemical impedance spectroscopy (EIS) and salt spray tests. Nano structure of the coated specimens was studied after salt spray tests using SEM-EDX analysis. Micro Chromatography (M-Ct) technique was employed to investigate the pore formation in the epoxy matrix. Besides, atomic force microscopy (AFM) was introduced to study surface roughness. The test results displayed a notable improvement (5–10 %) in tensile strength upon the introduction of nano silica. Taber tester results showed a reduction in mass loss with the addition of nano silica. Electrochemical impedance spectroscopy (EIS) studies further established a significant increase in corrosion resistance, having an impedance of 12 GOhm.cm2 for epoxy matrix samples containing 2.5 % nano silica after a 768-h salt spray test. SEM-EDX analysis revealed the absence of iron content in the epoxy matrix reinforced with uniformly distributed nano silica. Surface roughness assessments illustrated that nanolaminates contributed to an increase in overall roughness, minimizing surface irregularities in the epoxy matrix. Micro-CT scanning results proposed a decrease in epoxy matrix porosity upon the addition of nano silica. AI based prediction model helped to understand the relationship between surface roughness and corrosion. In summary, the experimental findings suggest valuable insights for future advancements in the development of protective coatings for worldwide civil infrastructures.

Defending against fluorine corrosion: Insights from FeCoNiCrMo high-entropy alloy behavior in hydrofluoric acid solutions

The surging demand for advanced fluorine corrosion-resistant materials underscores their significance in ensuring operational safety and reliability across various industries. This study investigates the corrosion behavior of the FeCoNiCrMo high-entropy alloy (HEA) via a series of 28-day immersion tests in hydrofluoric acid (HF) solutions. The results demonstrate the FeCoNiCrMo HEA's superior corrosion-resistant performance in HF environments, exhibiting remarkably low corrosion rates of 0.179 mm/y, 0.276 mm/y, and 0.352 mm/y in 20 vol%, 30 vol%, and 40 vol% HF solutions, respectively. Comprehensive phase and microstructural characterizations were conducted on samples exposed to the 40 vol% HF solution to elucidate the corrosion mechanisms. The study revealed that localized pitting corrosion preferentially initiates within the interdendritic regions of the HEA matrix upon HF exposure. During the intermediate stage, micro-galvanic corrosion occurs between the dendritic arms and interdendritic regions, leading to the formation of a uniform and compact corrosion product film on the alloy surface. This film, enriched with Mo, Cr, and O, provides temporary protection. However, as corrosion progresses, the partial detachment of particulate corrosion products compromises the integrity of the film, resulting in increased dissolution within the interdendritic regions and the formation of irregular corrosion grooves in the later stage. These insights significantly enhance the understanding of the corrosion mechanisms of FeCoNiCrMo HEA in HF environments and provide valuable guidance for developing innovative protective materials designed for fluorine-rich engineering applications.

One-Step Air Spraying of Structural Coating on Cu Alloy as Superhydrophobic Surface for Enhanced Corrosion Resistance and Anti-Icing Performance.

With the development of modern technology, the construction industry, and navigation technology, the metal Cu alloy has become an important metal material in mainstream industrial applications. As an indispensable basic metal material in the field of science and technology, its problem with corrosion is still a long-term problem that scientists have been working to solve. In this paper, air spraying technology is used to prepare an Al2O3-PDMS composite coating. By adjusting the content of Al2O3, the surface of the Cu alloy can reach different wetting states. The results show that the corrosion potential of the as-prepared superhydrophobic Al2O3-PDMS coating increases by 70 mV compared with the substrate, the corrosion current density decreases by one order of magnitude, and the impedance modulus increases from 2000 to 12,000 Ω⋅cm2, indicating a significantly enhanced corrosion resistance. It also possesses excellent anti-pollution and anti-icing behaviors, thereby allowing them to work in harsh industrial conditions.

The Effect of Hatch Spacing on the Electrochemistry and Discharge Performance of a CeO2/Al6061 Anode for an Al-Air Battery via Selective Laser Melting

To improve the electrochemical activity and discharge performance of an aluminum-air (Al-air) battery, a commercial 6061 alloy (Al6061) was selected as the anode, and CeO2 was also added inside the anode to enhance its performance. The CeO2/Al6061 composite was prepared using selective laser melting (SLM) technology. The influence of hatch spacing on the forming quality, corrosion resistance, and discharge performance of the anode was studied in detail. The results showed that with an increase in hatch spacing, the density, corrosion resistance, and discharge performance of the anode first increased and then decreased. When the hatch spacing is 0.13 mm, the anode has the best forming quality. At this point, the density reaches 98.39%, and the self-corrosion rate (SCR) decreases to 2.596 × 10−4 g·cm−2·min−1. Meanwhile, the anode exhibits its highest electrochemical activity and discharge voltage, which is up to −1.570 V. The change in anode performance is related to the defects generated during the SLM forming process. For samples with fewer defects, the anode can dissolve uniformly, while for samples with more defects, the electrode solution is prone to penetrate the defects, causing uneven corrosion and reducing electrochemical and discharge activity.

Sustainability inspired fabrication of next generation neurostimulation and cardiac rhythm management electrodes via reactive hierarchical surface restructuring

Over the last two decades, platinum group metals (PGMs) and their alloys have dominated as the materials of choice for electrodes in long-term implantable neurostimulation and cardiac rhythm management devices due to their superior conductivity, mechanical and chemical stability, biocompatibility, corrosion resistance, radiopacity, and electrochemical performance. Despite these benefits, PGM manufacturing processes are extremely costly, complex, and challenging with potential health hazards. Additionally, the volatility in PGM prices and their high supply risk, combined with their scarce concentration of approximately 0.01 ppm in the earth’s upper crust and limited mining geographical areas, underscores their classification as critical raw materials, thus, their effective recovery or substitution worldwide is of paramount importance. Since postmortem recovery from deceased patients and/or refining of PGMs that are used in the manufacturing of the electrodes and microelectrode arrays is extremely rare, challenging, and highly costly, therefore, substitution of PGM-based electrodes with other biocompatible materials that can yield electrochemical performance values equal or greater than PGMs is the only viable and sustainable solution to reduce and ultimately substitute the use of PGMs in long-term implantable neurostimulation and cardiac rhythm management devices. In this article, we demonstrate for the first time how the novel technique of “reactive hierarchical surface restructuring” can be utilized on titanium—that is widely used in many non-stimulation medical device and implant applications—to manufacture biocompatible, low-cost, sustainable, and high-performing neurostimulation and cardiac rhythm management electrodes. We have shown how the surface of titanium electrodes with extremely poor electrochemical performance undergoes compositional and topographical transformations that result in electrodes with outstanding electrochemical performance.

A Study on Microstructural Evolution and Corrosion Behavior of Ti36-Al16-V16-Fe16-Cr16 High-Entropy Alloy Fabricated via Spark Plasma Sintering Technology

This study focused on the synthesis of Ti36-Al16-V16-Fe16-Cr16 high-entropy alloys (HEAs) through spark plasma sintering to ascertain their corrosion resistance performance. Varied sintering temperatures, ranging from 700 to 1100 °C were employed to discern their impact on the alloy's characteristics. The fabricated HEAs underwent characterization using scanning electron microscopy and X-ray diffraction. A potentiodynamic polarization measurement was employed to compare the electrochemical properties of HEAs sintered at different temperatures in sulfuric and chloride aggressive media. The study outcomes indicate that the HEA sintered at 1000 °C exhibited superior corrosion resistance compared to other HEAs at other temperatures. This study contributes valuable insights into the nuanced relationship between sintering temperature, microstructure, and corrosion resistance of Ti36-Al16-V16-Fe16-Cr16 HEAs.

Research of the anti-static and corrosion resistance of S-ZnO/m-SWCNTs/ FC composite coating

Abstract In order to solve the hazards caused by corrosion and charge accumulation in aircraft, electronic equipment, oil and gas pipelines, the corrosion resistance and anti-static performance of coatings need to be noted. In this study, monodisperse single-walled carbon nanotubes functional slurry (m-SWCNTs) was obtained by the combination of high-energy ultrasonic dispersion and non-covalent amphiphilic dispersant (PVP). In this way, the uniform dispersion of low-content m-SWCNTs in fluorocarbon composite coatings was achieved, and the micronano structured surface of the fluorocarbon composite coating was constructed by using the modified-ZnO in order to achieve superhydrophobicity. The results showed that the corrosion resistance of the fluorocarbon composite coating was further improved and the antistatic property of the composite coating met the use requirements, which was achieved through the synergistic effect of the m-SWCNTs network and the modified-ZnO. The resistivity of S-ZnO/m-SWCNTs/FC coating is 3.15 Ωm, acting as anti-static coating to reduce safety hazards, its corrosion current is 9.66×10−8 A/cm2, which is lower than bare steel by 3 orders of magnitude. Meanwhile, the composite coating owns the self-cleaning, superhydrophobic and organic solvent affinity, acting as oil-water separation coating. This research provides a new idea for the fabrication of multifunctional coating, elucidating the significant potential of its applications.

Facile fabrication of robust, multi-functional and superhydrophobic coatings with corrosion resistance and anti-icing performance

In this paper, a series of superhydrophobic coatings with varying n-SiO2 content were prepared using a simple one-step spray method. The coatings were characterized with SEM, XPS, electrochemical workstation, AFM, etc. The influence of n-SiO2 content on the micro-nanostructure of the coatings was investigated, as well as the elemental composition, the wettability, mechanical stability, chemical stability, and anti-icing performance. The results showed that as the n-SiO2 content increased, the wettability and anti-icing time of the coatings initially increased and then decreased. The optimal performance was achieved at an n-SiO2 content of 4.16 wt%, with a contact angle of 162.62°, a sliding angle of 4.17°, and an anti-icing time of 1095 s. Mechanical stability was improved with increasing n-SiO2 content, and the coatings lasted for 40 sandpaper abrasion cycles, 55 tape peeling cycles, and 31 icing/deicing cycles at 4.88 wt% of n-SiO2. The coatings demonstrated good chemical stability in neutral and acidic environments but failed in strongly alkaline conditions. Electrochemical tests revealed that the superhydrophobic coatings provided excellent protection, with the corrosion inhibition efficiency (η) of Q235 carbon steel reaching 99.99 % after coating compared to uncoated Q235 carbon steel.

(La0.2Ce0.2Gd0.2Er0.2Sm0.2)2Zr2O7 High-entropy ceramic-glass composite coating with a high corrosion resistance

In this work, a new type of high-entropy ceramic powder (La0.2Ce0.2Gd0.2Er0.2Sm0.2)2Zr2O7 was synthesized by sol-gel method and high-temperature sintering (1000 °C) method. Combing (La0.2Ce0.2Gd0.2Er0.2Sm0.2)2Zr2O7 and glass powder to prepare high-entropy ceramic-glass composite coating. The composite coating exhibits excellent seawater corrosion resistance and high-temperature resistance performance. The impedance values of composite coating are 2.36 × 106 Ω cm2 in 3.5 % NaCl solution for 24 h. The high-entropy ceramic-glass composite coating could withstand the high temperature of 600 °C for 30 days and remains tight and intact with stainless steel without falling out. This work shows that the (La0.2Ce0.2Gd0.2Er0.2Sm0.2)2Zr2O7-glass composite coating can provide long-term high-temperature and seawater corrosion protection for stainless steel and has good application prospects in the field of marine corrosion protection.

Enhancing corrosion resistance and heat transfer performance of fin-tube heat exchangers for closed-type heat-source towers by superhydrophobic coatings

Heat-source towers are essential components in heat-source tower heat pump systems, pivotal for achieving energy efficiency. Enhancing corrosion resistance and heat transfer performance for heat-source towers is important but challengeable. For solving this problem, this study aims to introduce a novel superhydrophobic (SHP) coating applied via a one-step electrodeposition method to enhance both corrosion resistance and heat transfer performance of fin-tube heat exchangers in closed-type heat-source towers. The superhydrophobic nature of the coating is validated by contact angle measurements, while its structural integrity and chemical composition are confirmed through various methods i.e., X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. Corrosion resistance tests indicate a significant improvement, with the coating showing a corrosion current density of 1.400 × 10−6 A/cm2 and a low-frequency modulus |Z|0.01 Hz of 1.50 × 10⁴ Ω cm2 after 30 days in a 15 wt% calcium chloride solution at 0 °C. Additionally, heat transfer experiments demonstrate a 42.5 % increase in heat transfer efficiency compared to uncoated fins under identical conditions, which present the significant heat transfer performance of the presently developed SHP coating. The key contribution of this research lies in the development and application of a novel SHP coating that significantly enhances the performance of heat-source towers. Moreover, the present findings suggest that implementing this SHP coating can substantially improve the durability and efficiency of heat-source towers, supporting the advancement of more sustainable building infrastructures.

Enhanced corrosion protection of steel strip through advanced Zn–Mg alloy coatings manufactured by Continuous Physical Vapor Deposition: A review

The growing global consensus on the “carbon peak and neutrality” has focused on high-strength steel, highlighting its critical role in enhancing energy efficiency, reducing emissions in the steel industry, and reducing the weight of automobiles. Traditional Electro-Galvanizing (EG) and Hot-Dip Galvanizing (HDG) technologies face challenges in meeting the surface protection demands of these applications. This limitation is evident with the development of Zn–Mg coated strip steel, which offers high corrosion resistance. Continuous Physical Vapor Deposition (CPVD) effectively addresses these issues in a sealed vacuum environment, drawing significant attention in the strip coating industry owing to its superior surface quality, diverse material options, and environmental advantages. This article reviews the latest advancements and current status of Zn–Mg alloy coatings prepared using the CPVD technology. It discusses the typical thermal evaporation process used in CPVD, traces the development history of CPVD coatings on strip steel, and examines the microstructure, corrosion resistance, and adhesion performance evolution mechanisms of Zn–Mg alloy coatings. By designing multilayer structures, adjusting the Mg composition, and implementing controllable heat treatments, the overall performance of the coatings is enhanced. This study also comprehensively analyzes the feasibility of applying multilayer, highly corrosion-resistant Zn–Mg coatings. Additionally, it identifies the main challenges in applying CPVD technology to Zn–Mg coatings on strip steel, such as the large-scale, stable, and low-cost mass production of typical processes and controlling the void content at multilayer interfaces. Finally, future research directions are anticipated, underscoring the potentially significant impact of further alloying and computer simulations in advancing steel surface treatments.

Properties and Applications of Supersaturated Metastable Alloys Obtained via Electrodeposition

Supersaturated alloys can exhibit superior properties and electrodeposition is a cost-effective and versatile technique to produce them. In this review, the chemical, mechanical and structural properties of supersaturated alloys are discussed, and connections with metallic glasses and high entropy alloys are also exposed. After discussing mechanisms causing supersaturation in electrodeposited alloys, an overview of the most important electrodeposited metastable alloys is provided, showing that they are mainly used as protective coatings able to improve corrosion resistance and tribological performance of a large variety of industrial components. Composition of the electrolytic baths and deposition parameters are also considered and discussed.

Incorporate biosafe additives into self-healing coating on Mg for enhanced interfacial biocompatibility recovery

Local defects in coatings allow aggressive electrolytes penetrate to the coating/substrate interface, accelerating the corrosion of the exposed Mg substrate and compromising its biocompatibility. In this work, self-healing calcium hydrogen phosphate dihydrate (DCPD) coating incorporated with 3,5-dinitrosalicylic acid (3,5-D) or 5-amino salicylic acid (5-A) is designed on Mg. The results reveal that the self-healing and corrosion resistance performance of DCPD improves after adding 3,5-D/5-A. Namely, incorporating 3,5-D/5-A into DCPD accelerates the self-healing process and repair the coating at the initial stage. The released 3,5-D/5-A additives could adsorb on the exposed Mg surface and combine with the Ca2+ ions to precipitate. The interfacial adsorption mechanism of 3,5-D/5-A additives is disclosed by quantum chemical calculation. The simultaneously responsive adsorption and deposition of additives during coating degradation increase the thickness and compactness of the deposition layer at the coating defects, further inhibiting corrosion and stabilizing pH. These findings suggest taking biocompatibility recovery into consideration of preparing self-healing coating for biomedical applications.

Evaluation of Corrosion Resistance Performance of Anti-Corrosion Reinforcements with Surface Damage

Evaluation of Corrosion Resistance Performance of Anti-Corrosion Reinforcements with Surface Damage

Designing a Microstructure of NiCo-LDH@CNTs@Carbon Foam for Efficient Electromagnetic Wave Absorption and Excellent Environmental Tolerance.

The constantly evolving environment imposes increasingly stringent demands on the mechanical qualities of materials employed for absorbing electromagnetic waves (EMWs). Therefore, there is an urgent need for advanced materials capable of efficiently absorbing EMWs and withstanding harsh electromagnetic conditions. In this study, the electrodeposition method was effectively used to synthesize nickel-cobalt layered double hydroxides (NiCo-LDHs) in a controlled manner on a composite structure of carbon nanotubes and carbon foam, creating an exquisite construction. The manipulation of the electrodeposition time facilitated the regulation of the density of the layered structure within the composite material, thereby significantly enhancing its polarization relaxation performance. Increased defect sites and interface polarization enhance impedance matching and the attenuation constant, resulting in greatly improved absorption performance. The optimized sample demonstrated exceptional wave-absorbing performance in comparative experimental analysis, attaining a maximum reflection loss of -58.18 dB. It also has an effective absorption bandwidth of 5.36 GHz at a wavelength of 2.28 mm. The exceptional isolation effect of LDH, coupled with the outstanding insulation ability of the porous carbon skeleton, confers remarkable corrosion resistance and thermal insulation performance on the composite material. Hence, this discovery offers novel insights into designing environmentally tolerant absorbent materials.

Construction and properties of graphene oxide hydrogen-blocking coatings

Compared with the composite coating with a single structure, the coating with a multilayer structure may possess better hydrogen barrier performance. Graphene oxide (GO) was chemically modified using polyethylene glycol diglycidyl ether (EGDE) to obtain modified graphene oxide (mGO). The introduction of epoxy groups in mGO would participate in the crosslinking reaction between the epoxy resin (EP) emulsion and the curing agent to improve the dispersion and adhesion of the middle layer in the sandwich structure. An EP/mGO/EP composite coating with a sandwich structure was prepared. The research found that the tightly stacked mGO middle layer in the sandwich structure played a crucial role. The average adhesion of the multilayer composite coating was about 9 MPa. The electrochemical impedance spectroscopy of layer 2-mGO composite coating showed that its modulus was up to 109 Ω cm2. The permeation current density ip and hydrogen content remained at low values of 1.38 μA and 1.34 ppm, respectively. The multilayer composite coating possessed not only excellent adhesion but also excellent corrosion resistance and hydrogen barrier performance.

Surface modification of Al-15Al2O3-0.3G powder metallurgical alloy induced by high-current pulsed electron beam

This paper investigates the effect of high-current pulsed electron beam (HCPEB) surface treatment with two, five, and eight pulses on Al-15Al2O3-0.3G prepared by powder metallurgy. The results show that the presence of graphene during HCPEB irradiation effectively controls the extension of microcracks. The surface hardness of the samples increased by 66.56% and the wear rate decreased by 68.98% after eight-pulse HCPEB treatment. The increase in hardness is attributed to the uniform dispersion of hard particles, fine grain strengthening, dislocation strengthening, and amorphous structure formation by XRD, SEM, and TEM analysis during HCPEB irradiation. The improvement in wear resistance was attributed to the increase in hardness. The corrosion current density in 5 wt. % NaCl solution decreased from 1.212 × 10−4 to 3.353 × 10−5 after eight-pulse HCPEB treatment; the improved corrosion resistance performance is attributed to the equilibrium structure induced by HCPEB treatment.

THE EFFECT OF A Cr-FREE FINGERPRINT-RESISTANT PASSIVATION FILM ON THE PERFORMANCE OF HOT-DIP 55 % Al-Zn COATED STEEL

Cr-free fingerprint-resistant hot-dip 55 w/% Al-Zn coated steel (CFAZCS) is a upmarket steel plate product that is widely used in consumer goods with high added value, such as LCD back panels for monitors, as well as various electrical and electronic products. Passivation is a crucial process in the production of CFAZCS, greatly affecting the overall performance of the CFAZCS product. A comprehensive evaluation of passivation films from different manufacturers on the performance of CFAZCS can assist production enterprises in optimizing and controlling the product quality according to the requirements of target customers. This article comprehensively tests and evaluates the performance of corrosion resistance, acid/alkali resistance, anti-yellowing/blackening, paint adhesion, abrasion resistance, fingerprint resistance, and the conductivity of mainstream, commercially available, Cr-free, fingerprint-resistant, passivation solutions, providing guidance for the selection of passivation solutions in production processes.