Aqueous Zn-ion batteries are considered as possible substitutes for Li-ion batteries because of their low cost, high safety and environment-friendly. However, the hydrogen evolution side reaction, passivation and dendrite of Zn anode in neutral water electrolyte seriously affect the stability and safety of the battery and hinder its application. Zn anode is the key part that affects the capacity, stability and cycle life of battery. Introduction of corrosion inhibitor into electrolyte is a simple and practical method to inhibit the corrosion of Zn electrode. In this review, the mechanisms related with dendrite formation, passivation and hydrogen evolution reaction of Zn anode in neutral electrolyte are introduced first, and then the countermeasures of using corrosion inhibitor to solve these three problems are summarized. The performance, stability and feasibility of practical application of various corrosion inhibitors for the protection of Zn anode are illustrated in terms of perspectives such as the adjustment of solvation structure, electrostatic shield, adsorption, and in-situ solid electrolyte interface etc. Finally, the future development direction of corrosion inhibitor-based protection method for Zn anode is also proposed.

Compared with traditional alloys, high-entropy alloys display bettercorrosion resistance, high-temperature wear resistance and comprehensive mechanical properties. Thus, high-entropy alloys can find their applications in some harsh environments where traditional alloys may not satisfy the requirements. This work focuses on the corrosion resistance of high-entropy alloys. The influence of commonly used alloying elements on the corrosion resistance of high-entropy alloys with BCC, FCC, FCC+BCC and HCP crystal structures in sodium chloride and acidic solution media was discussed. The effect of the interaction between metal elements on corrosion resistance of high-entropy alloys was briefly explained. The influence of grain size, dislocation density, and crystal structure on the corrosion resistance of high-entropy alloys was also discussed. The results show that the corrosion resistance of high-entropy alloys can be improved by increasing grain size or reducing dislocation density. Several methods for improving the corrosion resistance of high-entropy alloys such as heat treatment and anodizing treatment, as well as application of corrosion inhibitor, were summarized. Finally, suggestions and prospects for the future development of high-entropy alloys were put forward.

With more and more electromagnetic equipment was applied in corrosion environment, the effect of magnetic field on metal corrosion has become a factor that cannot be ignored. It has been found that the promotion or inhibition effect of magnetic field on metal corrosion depends on the specific working environment. It is generally believed that the magnetic field affects the electrochemical process of particle movement mainly through the Lorentz force and magnetic field gradient force, so that to affect the electrochemical corrosion process of metal, specifically in the corrosion of metal in the process of mass transfer, interfacial reaction and corrosion products of these three aspects. This paper summarizes the specific effects of the Lorentz force and magnetic field gradient force on the metal corrosion process in the presence of magnetic fields, and puts forward the direction of the future research and application of the influence of magnetic field on the corrosion process of metallic materials.

At present, the global low-carbon and green development is urgent, and the voice of hydrogen energy as a zero-carbon energy is rising. Hydrogen storage and transportation is an extremely important part of the hydrogen industrial chain, whilst, among others the pipeline transportation is the most economical and efficient way. However, the pipeline steel is in direct contact with hydrogen, and thus the issue of hydrogen induced damage has become a hot topic again. This review focused on the advancements of how are hydrogen molecules adsorbed and converted into hydrogen atoms on the steel surface and then permeated inwards, as well as the microscopic mechanism of hydrogen embrittlement. The relationships between the hydrogen embrittlement susceptibility with the properties of pipeline steel, such as strength, microstructure, hydrogen traps, and the external environmental factors, such as hydrogen partial pressure, temperature, and load, are summarized. The methods for preventing and inhibiting the hydrogen embrittlement of pipeline steel are further summarized. Finally, specific suggestions are proposed for the current difficulties in the study of hydrogen damage related with pipeline steel.

With the popularization and application of CO₂ flooding technology in oilfields, the CO₂ corrosion and corrosion-control becomes an urgent problem to be solved. CO₂ corrosion can easily cause the damage and failure of oil casing, and it is of great economic value and scientific significance to study the relevant corrosion mechanism and anti-corrosion measures. In this paper, the CO₂ corrosion mechanism is introduced, and the influence of temperature, medium flow rate, pH and other factors on the CO₂ corrosion rate is analyzed. By taking the actual operation conditions of oilfield exploitation and the influencing factors of CO₂ corrosion into consideration, the research progress of corrosion-resistant materials, corrosion inhibitors, metal plating and other measures are reviewed, and the advantages and disadvantages of these measures in the actual oilfield application are summarized. Among many measures, the amorphous alloy coating is prone to be passivated passivated in operating conditions of oilfields, which may act as an effectively barrier to protect the pipe steel substrate from corrosion attack by corrosive media, thereby enhance the service life of the pipeline. The result of comprehensive analysis shows that the anti-corrosion measures of metal coating have good economic benefits and application prospects, and the future research on anti-corrosion technology of metal coating is prospected.

Printed circuit board (PCB) was one of the indispensable basic components in the electronic system, once damaged will lead to the failure of the entire electronic system. Therefore, it was particularly important to understand the nature of corrosion failure of PCB in practical service. This paper summarized the main factors that lead to the corrosion failure of PCB, including the property factors related with materials and external environmental factors (temperature, relative humidity, corrosive gas, electric field, etc.), summarizing the advantages and disadvantages of different surface treatment processes, and concluding the synergistic effect of external environment factors on the corrosion failure mechanism of PCB. The main testing methods for corrosion failure research of PCB is summarized. The advantages and disadvantages of different testing methods in corrosion failure research of PCB were clarified, and the progress of common corrosion types of PCB in different service environments was summarized. Finally, the combination of environmental testing and simulation analysis was proposed to establish a PCB corrosion model that was more suitable for the actual service environment.

In molten salt reactors, the interaction between fission products dissolved in the fuel salt with the structural alloys is a critical issue. Notably, the presence of tellurium (Te) poses a significant challenge by inducing intergranular cracks (IGC) for high temperature Ni-based alloys. Herewith, the corrosion behavior of high temperature Ni-based alloy GH3535 exposed to Te vapor (i.e. the test alloy with nominal doses of 1, 6, and 10 mg/cm² Te powders respectively were vacuum sealed in a quartz tube) at 700^oC for 150 h was assessed by means of scanning electron microscope (SEM), electron probe microanalyzer (EPMA), and transmission electron microscope (TEM), in terms of corrosion products and Te diffusion behavior. Results reveal that a dual-layered corrosion product was observed on the alloy surface after being exposed to Te vapor for 150 h at 700^oC. The outer telluride layer comprised Ni₃Te₂, Ni₃Te_2.07, and Cr₂Te₃, exhibiting a thickness directly proportional to the Te concentration. The inner ones represented a diffusion layer containing elongated Te-rich phases resulting from the inward diffusion of Te into the alloy matrix. Te diffusion was observed predominantly along grain boundaries (GB), penetrating to deeper regions and segregating there. It follows that the findings may provide a meaningful reference for understanding the Te-induced IGC, namely, this diffusion process led to a conspicuous depletion of Ni, Fe, and Cr at GB, thereby facilitating significantly the occurrence of IGC.

Nanoparticles Co₃O₄ with peroxidase catalytic activity were co-deposited with Zn by electrodeposition to obtain a novel Co₃O₄-Zn composite coating on Q235 carbon steel. Ultrasound and sodium oleate (NaoI) were introduced during the co-deposition of Co₃O₄ and Zn, which strongly promoted dispersion and adsorption of Co₃O₄ on the co-deposited surface coating. The characterization by SEM and XRD revealed that Co₃O₄ was obviously dispersed into the Zn matrix. The addition of NaoI effectively increased the deposited amount of Co₃O₄ in the Co₃O₄-Zn coatings. Besides, the antimicrobial performance of the Co₃O₄-Zn coatings was evaluated with three typical fouling bacteria, namely, Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Pseudomonas aeruginosa (P. aeruginosa). Results showed that the coverage of these three bacteria on Co₃O₄-Zn coatings decreased over 98%, illustrating that the Co₃O₄-Zn coatings showed high and broad-spectrum antimicrobial performance. It was also found that the Co₃O₄-Zn coating in the presence of hydrogen peroxide (H₂O₂) produced superoxide radicals (·O{}_{\mathrm{2}}^{-}) and hydroxyl radicals (·OH), which played dominant roles in the antimicrobial process. Finally, the antimicrobial stability and corrosion resistance of the composite coatings were also verified, and it was found that the composite coatings exhibited good antimicrobial stability and corrosion resistance characteristics. The results of this study provide a new possibility for the development of bactericidal coatings of simulated enzyme catalyst and a new solution for green antifouling.

A wear-resistant and corrosion-resistant composite coating designed for application in polar ship icebreaking areas was developed with modified basalt powder (BP) and mica powder as filler, while epoxy resin (EP) as the matrix, which was then applied on FH36 Marine low temperature steel plate. Considering the requirements related with the presence of ice-seawater friction-corrosion coupling effect in the ice zone navigation, tests such as coating adhesion, hardness, corrosion resistance by seawater immersion, as well as simulated low-temperature ice load friction and wear by varying ice-loads at different temperatures. The results show that as the filler content of mica powder and basalt powder increased from 10% to 20% (in mass fraction), the adhesion between the low-temperature composite coating and the substrate decreased from level 1 to level 2, whereas, its Vickers hardness increased by approximately 20%, corrosion resistance was improved accordingly, and the friction coefficient exhibited a decreasing trend, resulting in a significant improvement of wear resistance by nearly 50%, demonstrating the wear-reducing effect. Additionally, with the decrease in temperature, the wear performance of the low-temperature coating for polar ships showed a decreasing trend followed by an increasing trend.Meanwhile, the wear rate decreased successively from 0.3151 mm³/(N∙m) to 0.0962 mm³/(N∙m) and then increased to 0.1949 mm³/(N∙m). The lowest wear rate and the best wear resistance were observed at 0°C, indicating that temperature has a significant impact on the wear performance of the coating. In sum, the higher aggregate content can significantly improve the low-temperature wear resistance of the composite coating, resulting in lower wear volume.

The extract of invasive alien weed Erigeron canadensis L. (ECE) was prepared by ultrasound-assisted extraction. The corrosion inhibition performance of ECE as a corrosion inhibitor on steel in 1.0 mol/L HCl solution had been investigated by means of mass loss measurement, electrochemical method and metal surface characterization. The results show that ECE has good corrosion inhibition performance on steel in 1.0 mol/L HCl solution, and the corrosion inhibition rate increases with the increase of ECE concentration. Among others the corrosion inhibition rate of 300 mg·L^-1 ECE at 40^oC is the best, reaching 93.7%. The adsorption of ECE on steel surface is consistent with Langmuir adsorption isotherm. The standard adsorption Gibbs free energy ranges from -28.37 kJ/mol to -27.60 kJ/mol at 20-50^oC, and adsorption is a mixed type of physical and chemical adsorption. The potentiodynamic polarization curves show that ECE is a mixed inhibitor corrosion inhibitor acting through "geometrical overlay effect". The Nyquist plot shows a single capacitive resistance arc, and the charge transfer resistance at the steel/acid interface increases with increasing ECE concentration, while the capacitance of the double layer decreases. Examination results of metallographic microscopy, atomic force microscopy (AFM), contact angle, FTIR and UV-Vis show that the adsorption of ECE induced the formation a corrosion inhibition film on the steel surface significantly slows down steel corrosion in HCl solution and enhances the hydrophobicity of the steel surface.

Corrosion of metallic materials, used as wellbore wall is a critical issue that influences the safety of carbon sequestration. This work focuses on understanding the corrosion behavior of casing steels in high-temperature and high-pressure CO₂ storage environments. Herein, the corrosion behavior of two steels N80 and 13Cr in supercritical CO₂-rich water phases containing impurities (SO₂, NO₂, and O₂) was investigated via a high-temperature and high-pressure reactor by various pressure and stress conditions, aiming to simulate the real service conditions of carbon sequestration. The corrosion rate of steels was determined with mass-loss method, while the films formed on the steel surface were characterized by means of scanning electron microscopy (SEM), X-ray diffractometry (XRD), and X-ray photoelectron spectroscopy (XPS). The results indicated that increasing the pressure led to higher rates of uniform corrosion and pitting corrosion for N80 steel. However, the pressure had inapparent effect on uniform corrosion of 13Cr steel, although severe pitting corrosion was observed by pressure of 20 MPa. Furthermore, the applied tensile stress could induce damage of the corrosion product scales on both N80 and 13Cr steels to certain extent, nevertheless, no cracks were observed on the surface of the steel substrate.

The natural passivation behavior of HRB400 steel in simulated concrete pore solution, i.e. a saturated Ca(OH)₂ solution with pH 12.5 was investigated via measurements of open circuit potential, electrochemical impedance spectra, and Mott-Schottky curves. The composition and structure of the passivation film were characterized by X-ray photoelectron spectroscope and atomic force microscope. Subsequently, the resistance to Cl^- attack of the passivation film formed by the natural passivation in saturated Ca(OH)₂ solution with varying pH values was further studied with dynamic potential polarization curve measurement, SVET technique, and SEM in terms of corrosion morphology and corrosion products. The results indicate that HRB400 steel requires at least 72 h to form a stable passivation film in simulated concrete pore solution, and the structure and composition of the passivation film are subsequently changed during the process. The stable passivation film exhibits excellent resistance to chloride ion attack with a critical chloride ion concentration range of 0.1 to 0.15 mol/L, which is well consistent with the results of SEM characterization.

Taking the commercial sacrificial anode alloy Al-Zn-In as reference, a novel alloy Al-Zn-In-Sn-La was designed and made. Then the performance of the two alloys in simulated conditions of shallow-sea and deep-sea was comparatively assessed via measurements of corrosion mass loss, open-circuit potential, potentiodynamic polarization curves, and potentiostatic polarization curves. Results showed that, the discharge capacity of the Al-Zn-In-Sn-La alloy was slightly higher than that of the commercial Al-Zn-In alloy in the simulated marine environments, which may be related to the breakdown of the integrity of the passive film and the improvement of the anion and cation vacancies of the passivation film to promote ion migration, due to the synergistic activation effect of In, Zn, and Sn. Meanwhile, the novel alloy presents current efficiency of 90.01%, which was much higher than 75.87% of the commercial alloy in shallow sea condition, similarly, that was 82.99% and 75.48% in the deep-sea conditions, respectively. All the actions of the low free-corrosion rate of the alloy, the weakened micro-galvanic effect between the precipitated phase along grain boundaries with the matrix, and the refinement of grain boundaries by rare earth elements to promote uniform dissolution may significantly promote the improvement of the current efficiency of the novel alloy. It is worth mentioning that, the discharge capacity of the two alloys are significantly reduced in the simulated deep-sea environment. Which may be ascribed to the lower temperature and oxygen content, the slow-down of dissolution and deposition rate of ions, which reduces the surface-active sites of the alloys, leading to the passivation of the sacrificial anode Al-based alloys. It is expected that the designment of high entropy alloys might be an effective approach to overcome the problem of low discharge capacity of sacrificial anode alloys in deep-sea environment, by significantly improving the solubility of active alloying elements, and thereby improving the deep-sea discharging performance.

Located on coastal areas, facilities and pipelines serviced at high temperature will encounter from humid-hot corrosive environments for a long period, which can lead to deterioration of their thermal insulation coating. In this study, nano-ZrO₂ particles modified corrosion-resistant and thermal insulated epoxy coatings were prepared and characterized in terms of salt water resistance, salt fog resistance, cold and heat shock resistance and thermal insulation performance. The results showed that the corrosion resistance and thermal insulation stability of nano-modified coatings in corrosive environments could be significantly improved. The improvement effect was the best when 3% nano- ZrO₂ particles was added, but the ideal protective performance could not be achieved when the content was too small or too much.

With the rapid development of utilization and exploitation of deep-sea resources, the demand of marine engineering structural materials with lightweight and corrosion-resistant becomes urgent. TC4 alloy has attracted widespread attention for its excellent strength and corrosion resistance in seawater. Herein, the electrochemical behavior and friction-wear performance of TC4 alloy in simulated seawaters with different pH value is studied. The alloy performs better in the neutral simulated seawater (pH = 7) rather than in the acidic ones (pH = 2). After examination of the friction and wear behavior of TC4 alloy in the simulated seawater, it is indicated that the presence of seawater is favorite the reduction of the friction coefficient and wear loss. The existence of the seawater made the wear mechanism changed from the oxidative- and abrasive-wear in air to the corrosive- and fatigue-wear. At the same time, through the experiments by the combination of electrochemical corrosion-wear loading in the simulated seawater, it follows that by the combined action of sea water and the cyclic wear load, the passivation film on the TC4 alloy surface may experience alternating damaging- and repairing-processes. When the damage speed of passivation film exceeds repair speed, its protective effect no longer exists, in other word, the damaged passivation film may accelerate the TC4 alloy corrosion. However, when the cyclic load is removed, the passivation film of TC4 alloy may completely be repaired in the simulated seawater.

The effect of MnS inclusions with different sizes on the corrosion behavior of HRB400E rebar steel in 2%NaCl solution was investigated by means of automatic inclusion analyzer, immersion tests and Electron Backscattered Diffraction. The in-situ immersion test results showed that the localized corrosion was more easily induced by the relatively larger MnS inclusions than the smaller ones. The EBSD results suggested that corrosion was more likely initiated by inclusions with size above 40 μm², and this may be related to the presence of more low-angle grain boundaries and higher dislocation densities around them. Meanwhile, compared with the pit induced by a single inclusion, the width of pits initiated by clusters of large-size inclusions were greater.

The corrosion behavior of four steels 30CrMnSiA, 30CrMnSiNi2A, 300M and A100 for amphibious aircraft landing gear in an artificial seawater was studied through immersion testing, electrochemical methods, microscopic morphology, three-dimensional morphology observation, and corrosion product characterization. In addition, the effect of pre-corrosion on the corrosion fatigue performance of the four steels was also investigated. The results show that the electrochemical behavior of the four steels is similar: i.e. the anodic curve exhibits active dissolution characteristics, and the cathodic process is dominated by oxygen reduction reaction. The corrosion rate of the four steels may be ranked in the following order: 30CrMnSiNi2A > 300M > 30CrMnSiA > A100. Their corrosion products are consisted mainly of α-FeOOH, γ-FeOOH, α-Fe₂O₃, and Fe₃O₄. The four steels show uniform corrosion characteristics in artificial seawater environment. After a pre-corrosion treatment, the fatigue property of the steels 30CrMnSiA, 30CrMnSiNi2A and 300M may be deteriorated, but A100 steel is suffered from little effect. The A100 steel presents better seawater corrosion resistance than the other three, mainly because its much higher Co, Ni and Cr content, so that results in corrosion products of better protection performance.

The effect of Ag micro-alloying on the microstructure and corrosion behavior of the as-casted Mg-2Zn-0.2Ca (ZX20) alloy were investigated by means of OM, SEM, electrochemical tests, and hydrogen evolution mass loss method. The results reveal that the addition of 0.5% (mass fraction) Ag affects adversely the corrosion resistance of ZX20 alloy. The corrosion rate increases from 1.63 ± 0.17 mm/a for the ZX20 alloy to 4.06 ± 0.68 mm/a for the Ag-containing alloy (ZXQ200), primarily due to the potential difference between the second phase and the matrix. The dendrite arm spacing of the ZX20 alloy (69.8 ± 24.9 μm) is smaller than that of the ZXQ200 alloy (85.9 ± 23.9 μm), potentially contributing to the greater local corrosion depth observed in the ZXQ200 alloy. The two alloys all consist of α-Mg and Ca₂Mg₆Zn₃ phases with a similar volume fraction of the second phase, and no Ag-rich compounds have been detected for the Ag-alloyed ones. However, the Ag segregation in the second phase results in a heightened potential difference between the second phase and the substrate, elevating it from approximately 60 mV (ZX20) to about 200 mV (ZXQ200). This segregation enhances the micro-galvanic corrosion driving force in the ZXQ200 alloy, resulting in a shorter pitting gestation period and an increase in local corrosion sites.

The effect of aging treatment at 400-500^oC for different times on the microstructure and pitting resistance of Custom455 martensitic age-hardening stainless steel was investigated using OM, XRD, TEM and electrochemical methods. The results show that the microstructure of the ageing-treated steels consists of lath martensite and reversed austenite, and with the change of aging temperature and time, the second phase particles such as Cu-rich phases and Ni₃Ti with varying amount and size will be precipitated. For a given aging time, while the aging temperature increased, the amount of reversed austenite will also gradually increase, however the amount and size of Ni₃Ti, ε-Cu and other second-phase particles will not change obviously, so that the pitting corrosion resistance of the steel increased; when the aging temperature rises to 600^oC, a large number of the second-phase particles of Ni₃Ti, ε-Cu and others precipitate out, which leads to a decrease in the pitting corrosion resistance of the steel. When the aging temperature is consistent while the aging time rises to 3 h, the amount of reversed austenite in the steel does not change significantly, but the amount and size of Ni₃Ti, ε-Cu and other second-phase particles change significantly with the increasing aging time, which also leads to a decrease in the pitting corrosion resistance of the steel.

The impact of laser shock peening (LSP) on the microstructure and oxidation behavior of the nickel-based single crystal superalloy was investigated. The samples underwent LSP treatment, followed by oxidation for 10 and 150 h at 980^oC. The microstructure, microhardness, and oxidation morphology of this alloy without and with LSP treatment were comparatively examined. Finally, the mechanism by which LSP affects the oxidation behavior of this alloy was elucidated. The result shows that after a single impact, the surface of the specimen manifested some grid-like dislocations distribution, alongside an increment in microhardness from an initial value of 420 HV to 495 HV. After three impacts, the dislocations on the surface appeared more uniformly distributed with evident entanglement, culminating in an elevation of surface microhardness to approximately 590 HV. Furthermore, the dislocations generated on the surface by LSP promoted the formation of diffusion pathways during the oxidation process, which facilitated the early formation of a continuous protective oxide scale. It decreased the formation of poor Al pits, which resulted from the development of a protective oxide scale in the subsequent stages of oxidation, thereby reducing the spalling of the oxide scale.

The corrosion behavior of hot-dip galvanized coating on the Q235 steel plates commonly-used in grid equipment by applied bending stress was studied via immersion test in 0.05 mol/L NaCl solution while applied bending stress with a home-made three-point bending stress loading device. The results showed that by the applied bending stress, the corrosion of the hot-dip galvanized coating on Q235 steel plate was a process of repeated formation and spallation of corrosion products, of which the former involves apparently the occurrence of corrosion pits, while the later does not. The corrosion products were mainly composed of ZnO, Zn(OH)₂ and Zn₅(OH)₈Cl₂·H₂O. As the applied stress increased, the E_corr was decreased, but the I_corr and the electrochemical impedance were increased for the hot-dip galvanized coating on Q235 steel plate. A corrosion model was established to illustrate the corrosion process and the relevant mechanism for the corrosion of the hot-dip galvanized coating/Q235 steel plate. That is, the corrosion of the hot-dip galvanized coating was speeded by the applied bending stress to form more corrosion product Zn₅(OH)₈Cl₂·H₂O, which induced the formation of cracks at the stress concentrated sites beneath the corrosion product, i.e., the corrosion pits in η-Zn layer. The cracks then penetrated through the η-Zn layer, and extended along the interface ζ-FeZn₁₃/η-Zn. As a result, electrochemical corrosion of the galvanized coating was accelerated.

Balanus reticulatus is a macrofouling organism that is widespread in the sea areas of China and lots of sea areas in the world. Herein, the effects of surrounding factors on the settlement of Balanus reticulatus cyprids on the TC4 Ti-alloy and the glass which are highly biocompatible were investigated via observations of the settlement of Balanus reticulatus cyprids. The results showed that the settlement ratio on the TC4 Ti-alloy surface and the settlement ratio on the overall surface of TC4 Ti-alloy and glass reached the maxima when pH was 8 for the artificial seawater, which were 10% and 76.7%, respectively. The highest settlement ratio 73.3% on the overall surface of TC4 Ti-alloy and glass was in the seawater of 25‰ salinity, whereas the highest settlement ratio 6.67% on the TC4 Ti-alloy in seawaters of salinity between 13‰ to 18‰. The temperature and the flow velocity of the seawater also influenced the cyprid settlement significantly. At 10^oC, the cyprids did not settle. However, the settlement ratio on the TC4 Ti-alloy and the settlement ratio on the overall surface of TC4 Ti-alloy and glass were 10% and 50% at 25^oC, respectively. The corresponding two settlement ratios all reached the highest values in the still seawater. The cyprids did not settle when the seawater flow velocity was 12 m/s. These results threw a light on the anti-biofouling for marine facilities.

The diffusion behavior of benzotriazole and sodium benzoate in low-density polyethylene of volatile corrosion inhibitor film was studied via a constant temperature and humidity chamber at different temperature, as well as molecular dynamics simulations at the molecular level, comparatively. The effect of the shape and size of the corrosion inhibitor molecules, temperature, free volume of the diffusion system, self-diffusion in low density polyethylene, and the interaction energy between the corrosion inhibitor molecules, and the low-density polyethylene on the diffusion rate of the corrosion inhibitors was analyzed. The results show that the diffusion rate of benzotriazole and sodium benzoate in the low-density polyethylene increased with increasing temperature, moreover, the diffusion rate of the single benzotriazole was less than that of sodium benzoate. When co-existence of benzotriazole and sodium benzoate in the polyethylene, their diffusion rates lowered in contrast to that the polyethylene containing only one inhibitor either benzotriazole or sodium benzoate, and which decreased with the increasing sodium benzoate content. The interaction between the corrosion inhibitor molecules and the interaction between the corrosion inhibitor and the diffusion system were important factors affecting the diffusion of the corrosion inhibitor, and the diffusion of sodium benzoate may have an inhibitory effect on the diffusion of benzotriazole. The measured and simulated diffusion coefficients of benzotriazole in low-density polyethylene show the same variation trend, but their values differ by one order of magnitude. Even so, the result can still provide a technical reference for release control and formulation of corrosion inhibitors.

The oxidation behavior of F55 duplex stainless steel in 1.013 × 10⁵ Pa pure oxygen at 800, 900, 1000℃ has been studied by means of thermal gravimetric analyzer, optical microscope, scanning electron microscope (SEM) and X-ray diffraction (XRD). The results show that the oxide scales are mainly composed of Cr₂O₃ and Cr-Mn oxides at the designed temperatures. The oxidation kinetics curves follow parabolic law, and the oxidation mass gain increases with the increase of temperature. During the oxidation process, the α phase on the surface of the alloy changes into γ phase due to the outward diffusion of Cr, while the α phase in the matrix undergoes eutectoid reaction to form σ + γ and other phases. Cr in the σ phase generated by the eutectoid reaction preferentially diffuses to the surface of the alloy to participate in the oxidation reaction.

The corrosion behavior of Cu-Zn probe, used for atmospheric corrosion monitoring (ACM), was studied at different temperatures via salt spray testing with NaCl solutions, NaHSO₃ solutions, and NaCl and NaHSO₃ mixed solutions of varying concentration respectively. Correspondingly, the variation of the integrated charge quantity of Cu-Zn probes was also acquired with the testing conditions. The results indicate that the Cu-Zn probe is highly sensitive to the variation of test temperature, NaCl concentration, NaHSO₃ concentration, and the concentration of the mixed ones, exhibiting significant sensitivity. On the basis of comprehensive consideration of various factors, the order of corrosion impact for Cu-Zn probes is as follows: temperature < NaCl concentration < NaHSO₃ concentration < concentration of NaCl and NaHSO₃ mixture.

Effect of temperature on the corrosion behavior of 42CrMoE low alloy steel in boric acid solution was investigated using electrochemical measurements and immersion tests, taking 42CrMoE steel for fasteners of pressurized water reactor (PWR) primary system as the research object. The results showed that the increase in temperature promotes the anodic dissolution and cathodic reaction process of 42CrMoE steel in boric acid solution, resulting in a decrease in its corrosion resistance. Its corrosion type gradually evolved from uniform corrosion at low temperature to local pitting corrosion at high temperature. Moreover, the corrosion rate of 42CrMoE steel increases significantly with the increase of temperature, which is caused by accelerating the corrosion process of boric acid medium and reducing the stability of corrosion products. In addition, the corrosion rate first decreases and then increases with the elongation of the immersion cycle, and the corrosion rate can reach 1.3 mm/a at 97.5^oC.

In this paper, a high-entropy alloy Fe₃₄Cr₃₀Mo₁₅Ni₁₅Nb₃Al₃ was prepared via vacuum induction melting technique. The cast alloy consists of FCC phase, Laves phase and B2-NiAl phase. Then, the high-entropy alloy was subjected to corrosion test at 500^oC in static molten Pb-Bi eutectic (MBE) containing 10^-6% oxygen (in mass fraction) for 1000, 1500 and 2000 h, respectively. The results showed that after corrosion test, the high entropy alloy did not show obvious signs of being attacked by molten Pb-Bi eutectic, namely, there was no obvious dissolution of alloy components and phase transformation, and no obvious inward permeation of Pb and Bi from MBE into the alloy. Only a continuous Fe-Cr spinel scale was formed on the Laves phase region after static corrosion from 1000 h to 2000 h. It is worth mentioning in particular that after exposure for 1000 h, both of Fe-Cr spinel and Cr-depleted Fe-Cr spinel was formed on the surface of FCC/B2-NiAl phase region. As the corrosion time increased to 1500 h, the outer scale of Cr-depleted Fe-Cr spinel formed on the FCC/B2-NiAl phase region spalled off. After exposure for 2000 h, Fe₃O₄ was generated above the Fe-Cr spinel scale, and covered the entire surface of FCC/B2-NiAl phase region. In conclusion, the oxide scales formed on the high-entropy alloy are very thin and compact, with a maximum thickness less than 3 µm, so that the high-entropy alloy presented good resistance to MBE corrosion. The outstanding corrosion resistance of high-entropy alloy may be attributed to the homogeneous distribution of Laves phase, which effectively suppresses the outward diffusion of components of the high-entropy alloy.

A study was conducted on the degradation behavior of an epoxy corrosion-resistant coating in NaCl solution, focusing on the electrochemical impedance, water absorption, and adhesion of the coating. The results indicated that the coating still exhibits good protective performance after immersion for 5350 h. Meanwhile, a correlation between the changes in electrochemical impedance, water absorption, and adhesion of the coating was observed. The physical/chemical reaction between the electrolyte solution and the resin material might be the main mechanism of the coating degradation, with temperature being a significant influencing factor and the effect of coating thickness being less apparent.

Pt coatings were successfully deposited on the surface of TA4 Ti-alloy using the DC pulse magnetron sputtering technique. With the increasing deposition time, the lattice constants of Pt coating increased from 0.39112 nm at 5 min to 0.39128 nm at 15 min, correspondingly the thickness increased from approximately 0.29 μm to around 0.95 μm. Electrochemical studies revealed that the open circuit voltage (OCP) of Pt-coated TC4 was approximately 0.77 V higher than that of the plain TA4. With the extension of deposition time, the interfacial electrochemical reaction resistance further increases, as a result, its charge transfer resistance will gradually increase with deposition time as described as below: 5.52 × 10⁴, 5.91 × 10⁴, and 6.1 × 10⁴ Ω·cm², respectively. Importantly, the Pt coating effectively enhanced and maintained the excellent interface conductivity, as the interface contact resistance (ICR) only exhibited a slight increase after a simulated steady-state polarization testing. In sum, the Pt coating can significantly enhance the interfacial conductivity of TA4 in the anode side environment of proton exchange membrane hydrogen electrolyzer (PEMWE).