Corrosion Protection Of Metals Research Articles

PH-responsive capsule loaded with nitrogen-doped carbon dots for metal corrosion protection

In this study, a stimuli-release system based on mesoporous silica (MSN) loaded with nitrogen-doped carbon dots (N-CDs) as the core material and alginate cheating with Ca2+ as the wall materials were developed. The N-CDs were first synthesized via the solvothermal method, and then MSN@N-CDs were fabricated by stirring for 24 h. The controlled release system (MSN@N-CDs@Alg) was based on alginate cheating with Ca2+. The microstructure and chemical composition of N-CDs, MSN@N-CDs, and MSN@N-CDs@Alg were investigated. The pH-responsive release behavior and anticorrosion performance of the designed system were discussed. Results showed that the prepared N-CDs had a size distribution of 3–5 nm, and the loaded efficiency of MSN@N-CDs was 7.56%. Ultraviolet spectrophotometry measurements confirmed that the prepared capsule exhibited a higher release rate in alkaline conditions. Electrochemical measurements demonstrated that the capsule can release N-CDs intelligently following the corrosion degree of metal to improve the corrosion resistance. This safe, low-toxicity, and simple-to-prepare method can provide a new strategy for metal protection.

Polypyrrole-Modified Molybdenum Disulfide Nanocomposite Epoxy Coating Inhibits Corrosion of Mild Steel

The search for lightweight and low-cost anticorrosion coatings is particularly important in coastal environments with high salt and humidity. Graphene-based anticorrosion coatings are currently unable to provide long-lasting corrosion protection for metals because of their “corrosion-promoting activity”, and graphene-like materials, such as molybdenum disulfide (MoS2), are beginning to be anticipated its ability to protect against metals. This paper reported a simple method for preparing polypyrrole (PPy)-modified MoS2 nanomaterials from natural bulk MoS2. Their corrosion resistance behavior as fillers for epoxy (EP) resins was investigated in 3.5 wt.% NaCl solution. After the preparation of the MoS2 nanosheet dispersion by liquid-phase sonication using ethanol aqueous solution, the polypyrrole-coated molybdenum disulfide nanomaterials (MoS2@PPy) were directly obtained by adding pyrrole monomer to it in the presence of the initiator ammonium persulfate. Tafel polarization curves showed that the corrosion current of the MoS2@PPy/EP coating was 0.006 µA/cm2 after 15 days of immersion in 3.5 wt.% NaCl solution, much lower than that of pure EP coating (19.134 µA/cm2), effectively improving the anticorrosive properties of the coating. Overall, this study offered a practical method for the application of natural bulk MoS2 for corrosion protection.

Coating of Carbon Nanotubes Using Chemical Method to Enhance the Corrosion Protection of Copper and Aluminum Metals in Seawater Medium

In this study, carbon nanotubes were prepared using a pure chemical method modified similar to the Hummers method with simple changes in the work steps. The carbon nanotubes were then coated and reduced on copper and aluminum metals using the electrodeposition method (EDP) for corrosion protection application in seawater medium (NaCl 3.5%) at four different temperatures: 20, 30, 40, and 50 °C, which were studied using three electrode potentiostats. All corrosion measurements, thermodynamics, and kinetics parameters were nominated from Tafel plots. The films deposited by the carbon nanotubes were examined by the SEM technique, and this technique showed the formation of carbon nanotubes.

8‐Hydroxyquinoline‐functionalized chitosan Schiff base as an efficient and environmentally friendly corrosion inhibitor for N80 steel in acidic environments

AbstractChitosan is an environmentally friendly biomolecule with great potential for application in metal corrosion protection. First, Chitosan benzaldehyde schiff base (CTSB) and 8‐hydroxyquinoline functionalized chitosan benzaldehyde schiff base (HQ‐CTSB) were synthesized from chitosan, benzaldehyde, and 8‐hydroxyquinoline as high‐efficiency and environment‐friendly corrosion inhibitors. The structures of the synthesized products were characterized by infrared spectroscopy. The corrosion of N80 steel was tested using electrochemical measurements and analysis by varied concentrations of CTSB and HQ‐CTSB in a hydrochloric acid solution. The PDP results confirmed that both CTSB and HQ‐CTSB corrosion inhibitors were mixed corrosion inhibitors. Furthermore, the EIS findings revealed that the corrosion inhibition efficiency of the two inhibitors was 87.11% and 98.52% at 800 mg/L, respectively. According to SEM and XPS analyses, the CTSB and HQ‐CTSB molecules bonded to the surface of N80 steel and formed a surface protective layer. Density functional theory (DFT) calculations showed that CTSB and HQ‐CTSB have multiple active sites that may become adsorbent on the metal surface. And molecular dynamics (MD) simulations showed that corrosion inhibitors CTSB and HQ‐CTSB lie flat on the surface of Fe(110). The theoretical calculation agreed well with the experimental results.

Effect of calcium doping on the anodic behavior of E-AlMgSi (Aldrey) conducting aluminum alloy in NaCl electrolyte medium

The design of new materials intended for operation under severe conditions faces the task of rendering the materials corrosion resistant. The practical solution of this task is interrelated with the knowledge of corrosion protection of metals and alloys. The use of conducting aluminum alloys for the manufacture of thin wire may encounter specific problems. This is caused by the insufficient strength of these alloys and a small number of kinks before fracture. Aluminum alloys have been developed in recent years which even in a soft state have strength characteristics that allow them to be used as a conductive material. The E-AlMgSi (Aldrey) aluminum alloy is a well-known conducting alloy. This alloy is a heat-strengthened one, possessing good plasticity and high strength. After appropriate heat treatment this alloy acquires high electrical conductivity. Wires made from this alloy are almost exclusively used for air transmission lines. This work presents data on the corrosion behavior of calcium containing E-AlMgSi (Aldrey) aluminum conducting alloy in 0.03, 0.3 and 3.0% NaCl electrolyte medium. The anodic behavior of the alloy has been studied using a potentiostatic technique with a PI-50-1.1 potentiostat at a 2 mV/s potential sweep rate. Calcium doping of the E-AlMgSi (Aldrey) aluminum alloy increases its corrosion resistance by 15–20%. The corrosion, pitting and repassivation potentials of calcium doped alloys shift toward the positive region. An increase in the sodium chloride electrolyte concentration leads to a decrease in these potentials.

Effect of calcium doping on the anodic behavior of E-AlMgSi (Aldrey) conducting aluminum alloy in NaCl electrolyte medium

The design of new materials intended for operation under severe conditions faces the task of rendering the materials corrosion resistant. The practical solution of this task is interrelated with the knowledge of corrosion protection of metals and alloys. The use of conducting aluminum alloys for the manufacture of thin wire may encounter specific problems. This is caused by the insufficient strength of these alloys and a small number of kinks before fracture. Aluminum alloys have been developed in recent years which even in a soft state have strength characteristics that allow them to be used as a conductive material. The E-AlMgSi (Aldrey) aluminum alloy is a well-known conducting alloy. This alloy is a heat-strengthened one, possessing good plasticity and high strength. After appropriate heat treatment this alloy acquires high electrical conductivity. Wires made from this alloy are almost exclusively used for air transmission lines. This work presents data on the corrosion behavior of calcium containing E-AlMgSi (Aldrey) aluminum conducting alloy in 0.03, 0.3 and 3.0% NaCl electrolyte medium. The anodic behavior of the alloy has been studied using a potentiostatic technique with a PI-50-1.1 potentiostat at a 2 mV/s potential sweep rate. Calcium doping of the E-AlMgSi (Aldrey) aluminum alloy increases its corrosion resistance by 15–20%. The corrosion, pitting and repassivation potentials of calcium doped alloys shift toward the positive region. An increase in the sodium chloride electrolyte concentration leads to a decrease in these potentials.

UV-durable superhydrophobic ZnO/SiO2 nanorod arrays on an aluminum substrate using catalyst-free chemical vapor deposition and their corrosion performance

Dense ZnO nanorod arrays were obtained directly on Al substrate for the first time using catalyst-free chemical vapor deposition. The influence of temperature on the surface topography of ZnO nanostructures was analyzed. Then the ZnO nanorod arrays surface was coated with SiO2 films via pulsed laser deposition. After modifying with stearic acid, the Al/ZnO/SiO2 nanorod arrays showed superhydrophobic properties with a water contact angle of up to 157.9°. Notably, these Al/ZnO/SiO2 nanorod arrays exhibited UV resistance, and the water contact angle remained almost constant under UV light exposure for a long time. The electrochemical measurements showed that ZnO/SiO2 nanorod arrays had an excellent protective effect on metal Al. These results provided a basis for a feasible method for the corrosion protection of metals.

Epoxy Primer Coating Filled Microcrystalline Cellulose Treated with Silane Coupling Agent on Metal Substrate

Epoxy resin was incorporated with microcrystalline cellulose (MCC) for the production of the primer coating. Various sonication times were applied for the purpose of determining the ideal sonication period that provides the best barrier performance. The coatings were also added with various 3-Aminopropyltriethoxysilane (APTES) loadings in order to improve the mechanical and corrosion resistance properties. Fourier Transform Infrared (FTIR) Spectroscopy analysis was carried out to examine the chemical interactions and diffusion between MCC, APTES, and epoxy resin. After nine days of immersion in a 5% sodium chloride (NaCl) solution, the ideal sonication period was found to be 30 minutes, with no corrosion occurring aggressively and no flaking or blistering appears on the coating. The anti-corrosive qualities of the primer coating were eventually enhanced by the addition of MCC modified with APTES. The addition of APTES had improved the interaction between MCC and epoxy, hence achieving better compatibility and promoting a uniformly dispersed MCC throughout the epoxy resin matrix. The Tafel polarization results found that the addition of APTES up to 9% gave the lowest corrosion rate at 0.004 mm/year and the highest polarization resistances at 198.69 kꭥ. This is explained by the fact that enough MCC-APTES can serve as a physical barrier and obstruct the paths used by corrosive agent to diffuse. Therefore, the MCC-Epoxy treated APTES coupling agent for metal corrosion protection has thus been successfully created.

Honeysuckle extract as an environment-friendly corrosion inhibitor for copper in sulfuric acid medium

Corrosion protection of metals has been a key research field for researchers. Many researchers in the field of corrosion protection have devoted themselves to finding non-polluting corrosion inhibitors. A convenient and inexpensive method was used to extract honeysuckle using water as a solvent to obtain honeysuckle extract (HE). Here, we measured the anticorrosive effect of honeysuckle extract (HE) on Cu in 0.5 mol/L H2SO4 using various experimental methods and combined with a theoretical approach. The experimental results indicate that the maximum corrosion inhibition efficiency (η) of HE for Cu was close to 90%, and the value of η remained a steady state at different temperatures. The data fit revealed that HE is a hybrid corrosion inhibitor. The functional groups and chemical composition of HE as well as the surface of the HE-soaked copper samples were characterized by Fourier transform infrared spectroscopy (FTIR). X-ray photoelectron spectroscopy (XPS) is used to test the chemical state, chemical bonding, and other information on the copper surface. To observe the micromorphology of the acid-corroded Cu surface and the Cu surface under HE protection, Scanning Electron Microscope (SEM) was used. Atomic force microscopy (AFM) was used to compare and analyze three-dimensional morphological images and roughness information of Cu surfaces. Finally, quantum chemical calculations were used to perform theoretical calculations of the active ingredients in HE, using molecular dynamics simulations to model their adsorption behavior.

Role of conducting polymers in corrosion protection

Corrosion is an environmental evil related to metal and their alloys. Researchers trying their best to overcome it with traditional and new techniques. Recently Conducting polymers (CPs) such as polyaniline (PANI), polypyrrole (PPy) etc. are used for the corrosion protection of metals and metal alloys. Various mechanisms have been suggested to explain anticorrosion properties of CPs. These include anodic protection, controlled inhibitor release as well as barrier protection mechanisms. The presenting review is mainly focused on Different approaches that have been developed for the use of CPs in protective coatings.

Superior Anticorrosion Performance of Well-Dispersed MXene-Polymer Composite Coatings Enabled by Covalent Modification and Ambient Electron-Beam Curing

MXene-reinforced composite coatings have recently shown promise for metal anticorrosion due to their large aspect ratio and antipermeability; however, the challenges of the poor dispersion, oxidation, and sedimentation of MXene nanofillers in a resin matrix that are often encountered in the existing curing methods have greatly limited practical applications. Herein, we reported an efficient, ambient, and solvent-free electron beam (EB) curing technology to fabricate PDMS@MXene filled acrylate-polyurethane (APU) coatings for anticorrosion of 2024 Al alloy, a common aerospace structural material. We showed that the dispersion of MXene nanoflakes modified by PDMS-OH was dramatically improved in EB-cured resin and enhanced the water resistance through the additional water-repellent groups of PDMS-OH. Moreover, the controllable irradiation-induced polymerization enabled a unique high-density cross-linked network, presenting a large physical barrier against corrosive media. The newly developed APU-PDMS@MX1 coatings achieved excellent corrosion-resistance with the highest protection efficiency of 99.9957%. The coating filled with uniformly distributed PDMS@MXene promoted the corrosion potential, corrosion current density, and corrosion rate to be -0.14 V, 1.49 × 10-9 A/cm2, and 0.0004 mm/year, respectively, and the impedance modulus was increased by 1-2 orders of magnitude compared to that of APU-PDMS coating. This work combining 2D material with EB curing technology broadens the avenue for designing and fabricating composite coatings for metal corrosion protection.

Mussel-inspired preparation of superhydrophobic mica nanosheets for long-term anticorrosion and self-healing performance of epoxy coatings

Research and development of coatings with long-term corrosion resistance and self-healing capabilities remains an important and pressing topic in the field of metal corrosion protection. Adding functional fillers with superhydrophobicity and excellent polymer compatibility to the organic coating is an effective way to address this issue. In this work, inspired by mussels, functional mica nanosheets (MNs) were successfully prepared by interacting catechol groups of natural urushiol (Ur) with the surface of MNs, as validated by XRD, UV–vis, FTIR, XPS, and TGA. The synthesized MNs@Ur exhibited superhydrophobic properties (150° ± 1°) and great dispersion in solvents and epoxy resin, making them ideal nanofillers for enhancing the anticorrosive performance of epoxy (EP) coatings. The electrochemical impedance spectroscopy (EIS) results revealed that the obtained MNs@Ur/EP coatings had outstanding long-term corrosion resistance (>129 d). The impedance at low frequency (|Z|f=0.01 Hz) of the 0.5 wt% MNs@Ur/EP coating was maintained at >1010 Ω·cm2 after 52 d of immersion, which was approximately four orders of magnitude greater than that of the pure EP coating. More importantly, the scratch test demonstrated the self-healing ability of the MNs@Ur/EP coating.

Enhanced corrosion resistance of self-healing waterborne polyurethane coating based on tannic acid modified cerium-montmorillonites composite fillers

Nanofiller composite coatings with synergistic properties for long-term corrosion protection of metals. In this work, a new composite waterborne polyurethane coating with both self-healing and active corrosion protection was developed for the corrosion protection of carbon steel. The composite coating demonstrated remarkable long-term corrosion resistance thanks to the labyrinth effect of MMT and the synergistic action of corrosion inhibitors Ce3+ and TA. The impedance modulus was still above 108 Ω·cm2 after 50 days of immersion, which was nearly three orders of magnitude higher than that of the pure PU coating. Moreover, the self-healing experiments confirmed that the physical damage was effectively repaired after heat treatment, which was attributed to the disulfide bond exchange reaction. Importantly, the healed coating also exhibited durable corrosion resistance. This kind of double functional anti-corrosive coating shows great potential in the field of long-term anti-corrosion.

Study on the Preparation and Corrosion Resistance Properties of Superhydrophobic Coatings on Galvanized Steel

The method of atmospheric corrosion protection of metals has always been a research hot spot at home and abroad. In this paper, superhydrophobic coating is prepared on the surface of galvanized steel by chemical etching using 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES), graphene oxide (GO), anhydrous ethanol and water-based varnish as the main raw materials. The constitution of the superhydrophobic coating surface and the corrosion resistance of the steel are studied by electrochemical testing, X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS) and atomic force microscopy (AFM). Meanwhile, COMSOL software is used for the simulation of experiment. The results show that the surface of the superhydrophobic coating is composed of micro–nano sized papillary bulges, which play an important role in the improvement of metal corrosion resistance. The superhydrophobic coating effectively improves the alternating current impedance of the electrode and reduces the corrosion rate of the substrate. In addition, the results calculated by COMSOL software consist of the experimental results.

Study on the corrosion inhibition of biomass carbon quantum dot self- aggregation on Q235 steel in hydrochloric acid

At present, the development of efficient green corrosion inhibitors has become one of the important directions of metal corrosion protection. In this paper, biomass carbon quantum dots (BCQDs) were prepared by hydrothermal reaction using biomass precursors. The optical properties and structural composition of the synthesized BCQDs were characterized in detail. After that, the corrosion inhibition performance of BCQDs was evaluated by EIS, Tafel, SEM and TEM. The electrochemistry and surface tests demonstrate that the aggregates can effectively prevent Q235 steel from corrosion in 1 M HCl medium at 298 K-328 K, with the maximum inhibition efficiency of 94.1 % at the concentration of 200 mg/L at 308 K. Finally, the corrosion inhibition mechanism was analyzed by FTIR, CA and XPS on the surface of the corroded carbon steel samples. The inhibition mechanism suggests that BCQDs can inhibit metal corrosion by self-aggregation and adsorption on metal surface. This is owing to its small size effect and functional groups containing heteroatoms, easily forming dense protective film.

Electrochemical Behaviour of Silica Deposited on Stainless Steel by Electrophoretic Deposition

The purpose of this paper is to evaluate the characteristics of corrosion protection of stainless steel substrates coated with silica by electrophoresis with pulsed direct current (PDC) and constant direct current (CDC) with anodization. Electrophoresis was carried out using silica sol from sodium silicate solution as an electrolyte solution. Stainless steel functioned as an anode and carbon as a cathode with a constant electrode distance of 2 cm. The amplitude, duty cycle, and anodization effect on stainless steel corrosion protection characteristics were evaluated. The samples were characterized by linear polarization and electrochemical impedance spectroscopy (EIS) to see the characteristics of metal corrosion protection and scanning electron microscopy (SEM) analysis to see the morphology of the coating. This study showed that PDC electrophoresis and CDC accompanied by anodization could obtain silica film with good corrosion protection characteristics (high pore resistance and low admittance). Linear polarization results showed that metal corrosion protection behavior was increased by anodization. Similar results were obtained by EIS analysis which showed that pore resistance increased by anodization. The highest pore resistance obtained by the constant current with anodization is 543 ohms, and the lowest admittance is 0.0217. Corrosion protection characteristics are also influenced by the amplitude and duty cycle during electrophoresis. Silica film with a high pore resistance and a low admittance were obtained at a frequency, amplitude, and duty cycle of 80 Hz, 0.5 volts, and 60%, respectively. The silica film produced by pulsed electrophoresis resulted in better coating characteristics than by constant current with anodization, which is seen from the pore resistance value and its admittance.

Graphene-like two-dimensional nanosheets-based anticorrosive coatings: A review

• Prepartion of graphene-like 2D nanosheets are summarized in detail. • Surface functionalization of graphene-like 2D nanosheets are presented. • The anticorrosion performance, anticorrosive mechanism, and optimization measures of pure 2D nanosheets coatings and their composite coatings are reviewed. • Future development directions and challenges for graphene-like 2D nanosheets used for metal protection are proposed and discussed in detail. In recent years, graphene has been widely employed in the field of metal corrosion protection owing to its outstanding impermeability and chemical stability, with examples of such metal protection including pure graphene coatings and graphene-based composite coatings. But the conductive graphene could promote the electrochemical reaction at the interface and accelerate the corrosion of metal substrates. More emerging graphene-like 2D nanosheets are attracting research attention for the application of metal anticorrosion, because of their barrier properties and poor conductivity, mainly including boron nitride (BN), molybdenum disulfide (MoS 2 ), zirconium phosphate (ZrP), and titanium carbide (MXene). In this review, the application of these graphene-like 2D nanosheets to metal protection is comprehensively reviewed. First, the general preparation methods of 2D nanosheets are briefly introduced. Second, surface functionalization of 2D nanosheets, including covalent and non-covalent modification, is described in detail. Third, the anticorrosion performance and optimization measures of pure 2D nanosheets coatings are summarized. Next, the protection performance, anticorrosive mechanism, and optimizations of 2D nanosheets composite coatings are presented. Finally, the future development of 2D nanosheets-based anticorrosive coatings has been prospected, and the challenges in the industrial application are discussed.

Study on preparation and anticorrosive performance of a new high hydrophobic anticorrosive coating

AbstractWater‐based anticorrosive coatings have poor water resistance, which easily lead to coating deterioration and metal corrosion. In order to improve the anticorrosion performance of waterborne coating, herein, the polytetrafluoroethylene/dimethyl siloxane/epoxy resin (PTFE/PDMS/EP) hydrophobic anticorrosive coating was prepared by layer‐by‐layer construction. The spatial structure and microscopic morphology of the hydrophobic coating were analyzed by XRD, FTIR, and SEM. The hydrophobicity and corrosion resistance of the composite coating were analyzed by hydrophobicity test, electrochemical polarization curve, hydrophobicity and corrosion resistance test of the mixed layer, Tafel polarization curves, and AC impedance spectrum. The results showed that the water contact angle of PTFE/PDMS/EP coating reached 141° and the protection efficiency of PTFE/PDMS/EP coating was 98.62%. After soaking for 7 days, the corrosion process still stays at the initial stage, which was mainly due to the good sealing and barrier properties and high anticorrosion efficiency of PTFE/PDMS/EP coating. The coating has high corrosion protection efficiency and long service life, which is of great significance to metal corrosion protection in harsh marine environments.

Development of Metallo (Calcium/Magnesium) Polyurethane Nanocomposites for Anti-Corrosive Applications

Long-term corrosion protection of metals might be provided by nanocomposite coatings having synergistic qualities. In this perspective, rapeseed oil-based polyurethane (ROPU) and nanocomposites with calcium and magnesium ions were designed. The structure of these nanocomposites was established through Fourier-transform infrared spectroscopy (FT-IR). The morphological studies were carried out using scanning electron microscopy (SEM) as well as transmission electron microscopy (TEM). Their thermal characteristics were studied using thermogravimetric analysis (TGA). Electrochemical experiments were applied for the assessment of the corrosion inhibition performance of these coatings in 3.5 wt. % NaCl solution for 7 days. After completion of the test, the results revealed a very low icorr value of 7.73 × 10-10 A cm-2, a low corrosion rate of 8.342 × 10-5 mpy, impedance 1.0 × 107 Ω cm2, and phase angle (approx 90°). These findings demonstrated that nanocomposite coatings outperformed ordinary ROPU and other published methods in terms of anticorrosive activity. The excellent anti-corrosive characteristic of the suggested nanocomposite coatings opens up new possibilities for the creation of advanced high-performance coatings for a variety of metal industries.

In-situ growth and excellent corrosion protection properties of molybdenum dioxide/boron nitride heterojunction composites

Molybdenum dioxide has been widely applied in various fields. Constructing novel molybdenum-dioxide-based heterojunction is prospective to expand the applications in metal corrosion protection. Herein, the novel molybdenum dioxide/boron nitride heterojunction composites were synthesized with a two-step calcination method. MoO2 nanoparticles were in-situ loaded on the surface of BN and formed a heterojunction structure. The total impedance values of MoO2/BN-1 (synthesized with melamine and boric acid) and MoO2/BN-2 (synthesized with urea, melamine and boric acid) coatings respectively increased to 314.7 % and 163.6 % of that of epoxy coating. It was attributed to synergistic effects consisted of the physical barrier effect, electron transport blocking effect and photo-induced corrosion protection effect. Synthesizing stabilized molybdenum oxide heterojunction with boron nitride carrier exhibited feasibility for practical corrosion protection application.