Steel Surface Research Articles

Corrosion behavior analysis of steel in simulated carbonated concrete pore solution based on 3D optical microscopy method

The main purpose of this study was to analyze the corrosion behavior of steel in simulated carbonated concrete pore solution (SCCPS) with the help of 3D optical microscopy method. This method was adopted to provide qualitative observation of surface with 3D information and quantitative results of defects for steel which was affected by various NaCl contents and inhibitors (inorganic inhibitor (NaNO2) and organic inhibitor (DEA(C4H11NO2)). As the NaCl contents changed during all corrosion periods, the mean pitting depths (Ra) and NaCl contents showed stronger linear relationships, and the slop values presented as the Ra added value of per wt% for different inhibitor systems were all detected to be closed to 3 μm/wt% in all linear regression models. This method provided a new angle to investigate and estimate the defect variation on steel surface, which denoted to better understand the corrosion behavior in SCCPS. Additionally, electrochemical impedance spectroscopy (EIS) and weight loss measurements were also used to verify the results of 3D optical microscopy analysis.

Impact of surfactant groups on the corrosion inhibition properties of superhydrophobic membranes on X80 steel

Fe2O3/Fe3O4 composite films were successfully prepared on the surface of X80 steel through hydrothermal synthesis and annealing treatments. Subsequently, the oxidised films were modified using surfactants such as decanoic acid (DA), decyl silane triol (DS) and perfluorodecyl silane triol (FDS), resulting in the creation of three distinct films exhibiting superhydrophobic properties. The effects of the hydrophilic and hydrophobic groups of surfactants on the superhydrophobic films of X80 steel were analysed using electrochemical methods, surface analysis techniques and theoretical calculations. The results showed that all three superhydrophobic films exhibited excellent corrosion resistance, with the order being DA > FDS > DS after 72 h of immersion in acidic conditions (pH = 6, 60 °C). Theoretical calculations showed that the adsorption performance of carboxyl groups was superior to that of silyl alcohol bonds, whereas fluorination of hydrophobic groups helped to enhance the adsorption capacity of hydrophilic groups. This not only reveals the key role of surfactants in the preparation of superhydrophobic membranes but also provides a theoretical basis for the preparation of superhydrophobic membranes on carbon steel surfaces.

Fabrication of superhydrophobic, permeable, and anti-reflective porous steel surfaces using laser ablation and heat treatment

Fabrication of superhydrophobic, permeable, and anti-reflective porous steel surfaces using laser ablation and heat treatment

Synthesis and characterization of selenium-polyvinyl alcohol nanoparticles as eco-friendly corrosion inhibitor for carbon steel in 1.0 M H2SO4

Selenium nanoparticles capped with polyvinyl alcohol (Se-PVA NPs) have been synthesized by chemical reduction using ascorbic acid as a reducing agent. The synthesized nanoparticles were characterized using XRD, DLS, zeta potential, FT-IR, and TEM analysis and found to be stable. The solution of Se-PVA NPs was used as a carbon steel corrosion inhibitor in 1.0 M H2SO4. The effect of the presence of Se-PVA NPs in the corrosion medium was studied by potentiodynamic polarization and gravimetric analyses In the presence of Se-PVA NPs with a concentration of 600 ppm at 303 K, corrosion inhibition efficiency values of 92.86 % and 92.3 % were recorded by potentiodynamic polarization and gravimetric analysis methods, respectively. Over the Se-PVA NPs concentration range 100–600 ppm, it was found that increasing the concentration increases the inhibition efficiency, while the temperature has an adverse effect, inhibition efficiency values of 80.0 % was recorded at 323 K for the 600 ppm Se-PVA NPs solution. The potentiodynamic polarization measurements suggested that Se-PVA NPs work as a mixed-type inhibitor. The corrosion inhibition process was confirmed by testing the used specimens’ metal surface using SEM and AFM techniques, which showed that the acidic medium’s negative impact (distortion and roughness) on the carbon steel surface was reduced significantly in the presence of Se-PVA NPs. The inhibitor’s adsorption on the metal surface was studied. It obeys the Langmuir isotherm with a mixed-type adsorption process. The related kinetic and thermodynamic parameters were investigated.

Development of Hybrid Models Based on AlexNet and Machine Learning Approaches for Strip Steel Surface Defect Classification

Development of Hybrid Models Based on AlexNet and Machine Learning Approaches for Strip Steel Surface Defect Classification

Focusing on the corrosion resistance enhancement of HRB400 rebar by Cr addition in the marine environment

The corrosion resistance of Cr reinforced HRB400 rebar in the marine environment was investigated. The addition of Cr increases the amount of Cr(OH)3 and α-FeOOH in the passivate film, resulting in a denser passivate film structure. This enhanced passivation film inhibits localized corrosion. The pitting potential and critical chloride concentration (CTL) of the steel increased with the increase in chromium content, indicating improved corrosion resistance of the steel. On the other hand, an increase in the concentration of Cl- in solution leads to a decrease in the pitting potential and resistance of the steel, which reduces the corrosion resistance. At higher Cl- concentrations, the Cl- ions form an electrochemical interface with the steel surface, resulting in a sharp decrease in the Rf value. In addition, the gradual decrease in solution pH leads to a decrease in the pitting potential and CTL of HRB400 and 1.5Cr steel. The corrosion resistance was also found to be reduced, pH reduction accelerated the intrusion of chloride ions, which led to a severe breakdown of the passivation film.

Study of Nanostructured Layer Growth on Plasma-Facing Materials Irradiated with Helium Plasma

Tungsten and stainless steel samples were irradiated with stationary helium plasma in the plasma linear multicusp plasma device. The surface of the material is modified under the influence of helium plasma with the formation of nanostructures and microstructures on the surface. The fluence of helium ions equal to 8 × 1027 ions/m2 was achieved on the tungsten sample. Depending on the helium ion fluence, fuzzlike layers, loops, and bubbles of 20- to 500-nm scale were formed on the tungsten surface. The fuzz layer thickness depends on the duration of plasma irradiation in a wide range of fluence. Saturation of the growth of the thickness of the tungsten fuzz layer was observed at a fluence of more than 8 × 1026 ions/m2. The growth of microstructures and nanostructures on the surface of stainless steel irradiated with helium plasma was observed. The growth of nanostructured layers is explained by a theoretical model considering the dynamics of adatoms under the influence of plasma.

Understanding heterogeneity and anisotropy of Duplex Stainless Steel's elastic/plastic nature through property mapping technique

Accelerated property mapping, an advanced indentation technique was used to describe the nanomechanical behaviour of duplex stainless steel (DSS) surfaces prior to and post heat treatments. Heterogeneity in deformation responses and relative elastic and/or plastic nature of DSS was assessed on longitudinal and transverse directions through load–displacement curves, property maps, histograms of hardness (H), modulus (E) and indentation works. Empirical ratios such as H/E, (H/E)1/2, H3/E2 and plasticity index were employed to understand the anisotropy across the directions.

Investigation of the influence of nano-CrN concentration on the performance of Ni-W coatings in X80 pipeline steel

A novel nano Ni-W-CrN composite coating was developed for X80 pipeline steel to enhance its structural properties and corrosion resistance. The study explored the effects of varying CrN nanoparticle concentrations (0, 5, 10, 15, 20 g/L) in the deposition solution using techniques such as SEM, EDS, and XRD for analysis and an electrochemical workstation for corrosion testing. The optimal CrN concentration was identified at 10 g/L, resulting in a coating with peak hardness (811HV), low friction coefficient (0.16), minimal wear rate (1.18×10−4 mm3·(N·m)−1), and improved corrosion resistance. This coating significantly outperforms Ni-W alloy coatings in hardness, wear resistance, and elastic recovery, offering a promising approach for enhancing the performance of X80 pipeline steel surfaces.

A novel surface grain boundary engineering approach to improving corrosion resistance of a high-N and Ni-free austenitic stainless steel

Grain boundary engineering (GBE) can effectively improve the corrosion resistance of materials, but the traditional thermal-mechanical process still exhibits some limitations. In the present work, a novel surface spinning strengthening (3 S) technology followed by heat treatment was applied to modify the microstructure near the surface (∼ 400 μm) of a high-N Ni-free austenitic stainless steel. Under an optimal condition of annealing at 1323 K for 60 min after 3 S, the fraction of special boundaries mainly involving Σ3 boundaries in GBE layer was significantly improved from 48.3 % to 69.1 %, thus achieving excellent resistances to intergranular corrosion and stress corrosion cracking.

Synthesis and characterization of a new eco-friendly dopamine derivative schiff base as an effective corrosion inhibitor for mild steel in acidic environment

The natural corrosion inhibitor behaviour of a newly synthesized dopamine derivative Schiff base (4-DBAB) has been inspected on mild steel in aggressive 1 M HCl using linear polarization, electrochemical impedance spectroscopy and potentiodynamic polarization techniques. The Schiff base was synthesized by eco-friendly pathway. Characterization of the synthesized new non-toxic inhibitor was performed using FT-IR and 1H-NMR spectroscopy techniques. The anti-corrosive efficiencies at optimum concentration of 4-DBAB inhibitor was 87.4% after 1 h and 98.4% after 120 h by impedance technique in acidic solution. The potential of zero charge of mild steel was also determined to elucidate the inhibition mechanism in the presence of the highest 4-DBAB solution. The atomic force microscopy and field emission scanning electron microscopy researches performed on surface morphology to provide additional support on the interaction between the mild steel surface and 4-DBAB molecules. Adsorption behaviour of the inhibitor was also studied at different durations by experimental inhibition results and showed the Langmuir isotherm involving chemisorption. Highlights A new dopamine-derived Schiff base (4-DBAB) with natural and environmentally friendly corrosion inhibition properties was synthesized. (Synthesis of eco-friendly compound). 4-DBAB demonstrated a high anti-corrosive efficiency after 120 hours in aggressive 1M HCl, as determined by impedance technique. (Exceptional corrosion inhibition). The determination of the potential of zero charge of mild steel provided insights into the inhibition mechanism in the presence of the highest 4-DBAB solution. (Mechanism elucidation). AFM and FE-SEM studies on surface morphology supported the interaction between the mild steel and 4-DBAB molecules, affirming its corrosion inhibition properties. (Surface interaction analysis).

Spiking ViT: spiking neural networks with transformer—attention for steel surface defect classification

Spiking ViT: spiking neural networks with transformer—attention for steel surface defect classification

Antimicrobial and antibiofilm activities of Aleppo pine essential oil and enzymes against Salmonella enterica biofilms formed on stainless steel and plastic surfaces

Several foodborne illness outbreaks caused by Salmonella enterica have been associated with the presence of biofilms, particularly on food contact surfaces. The objectives of the current study were: i) to assess the minimum inhibitory (MIC) and minimum bactericidal concentrations (MBC) of Aleppo pine essential oil (APEO) against 5 S. enterica serotypes and their mixture in Tryptone Soy broth at 37 °C and, ii) investigate the antibiofilm activity of two mixtures of 3 hydrolytic enzymes (5% protease, 2.5% α-amylase, and 0.5% lipase or 10% protease, 5% α-amylase, and 1% lipase at 50 °C for 30 min, and APEO at 1, 2 and 4 MIC at 25 °C for 10, 20 or 30 min) as well as sequential use of enzyme mixtures and APEO against S. enterica on stainless steel and plastic surfaces. The results showed that the MIC and MBC values of APEO against S. enterica strains and their mixture were 250–500 μg/ml and 1000-4000 μg/ml, respectively. In general, the antibiofilm activity of enzymes and APEO increased as the concentration increased and exposure time was extended. The results showed that a 1.8 log CFU/coupon reduction (p < 0.05) was obtained using 4 MIC APEO for 30 min at 25 °C. The enzyme-based mixture containing 10% protease, 5% amylase and 1% lipase at 50 °C for 30 min reduced the microbial load of S. enterica in biofilms on stainless steel and plastic surfaces by 2.1 log CFU/coupon (p < 0.05). However, a sequential two-step treatment based on a mixture of 10% protease, 5% α-amylase, and 1% lipase for 30 min at 45 °C followed by 4 MIC APEO for 30 min at room temperature reduced the S. enterica cells in biofilms on stainless steel by 4.6 log CFU/coupon (p < 0.05). These results indicated that enzyme-APEO treatments may be applied as a natural alternative to overcome biofilm formation by S. enterica in the food industry.

Synthesis and characterization of bis-isoxazoline-thiosemicarbazone as a corrosion inhibitor for carbon steel: Experimental study, and molecular simulation

In this study, a novel compound, bis-isoxazoline-thiosemicarbazone (BIT), was synthesized and tested for its ability to protect carbon steel from corrosion in a 1 M HCl solution. The compound's structure was confirmed using spectroscopic techniques such as 1H NMR, 13C NMR, and HRMS. Various methods, including mass loss analysis, potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), SEM, and EDX, were employed to assess BIT's effectiveness in inhibiting corrosion and its adsorption behavior on carbon steel in acidic conditions. The findings demonstrated the high effectiveness of BIT as a corrosion inhibitor, with a 95 % inhibition rate observed at a concentration of 0.77 mM and a temperature of 298°K. Analysis through PDP revealed that BIT operates as a mixed-type inhibitor, conforming to the Langmuir adsorption isotherm during its attachment to the carbon steel surface, indicating a mixed (chemical-physical) adsorption process.SEM-EDX analysis demonstrated even distribution of the inhibitor on the steel surface. Notably, BIT contains several functional groups (methoxy, carbonyl, isoxazolyl,..) and heteroatoms (N, O, and S) that play a crucial role, as supported by Density Functional Theory (DFT) studies. Experimental findings were validated by DFT and molecular dynamics (MD) simulation data.

Experimental and computational exploration of the biodegradable platanus acerifolia leaf extract against mild steel corrosion in hydrochloric acid

This study delved into the potential application of Platanus acerifolia leaf extract (PALE) as an environmentally benign corrosion inhibitor. Evaluation of corrosion inhibition was conducted using electrochemical methods, field emission scanning electron microscopy equipped with energy dispersive spectrometer. The results reveal that PALE offers efficient protection for Q235 steel across the temperature range of 298 K–318 K, achieving a maximum corrosion inhibition efficiency of approximately 93%. Furthermore, Density functional theory (DFT) calculations and molecular dynamics (MD) simulations were performed to elucidate the spontaneous and stable adsorption of PALE molecules onto the surface of Q235 steel. This adsorption impedes the diffusion of corrosive substances towards the steel surface, thereby endowing Q235 steel with robust corrosion resistance.

Effects of Cl-ion and temperature variations on steel corrosion in supercritical CO2 saturated aqueous environments

This study explored the influence of Cl-ion and temperature variations on the corrosion behavior of pipeline steel in supercritical CO2 (s-CO2) saturated aqueous environments. The steel exposed to the s-CO2 saturated salt solution at 50°C shows a higher corrosion rate (CR) of 5.02 mm/year compared to that exposed to deionized (DI) water, which has a corrosion rate of 1.47 mm/year. This trend is more pronounced at higher temperatures. This performance enhancement is attributed to the formation of a dense and protective FeCO3 film, facilitated by the Cl-ion presence, with a more pronounced effect observed at higher temperatures. The corrosion mechanism, commencing with the impact of Cl- ions on interactions between CO2 and the dissolved HCO3- ions with iron at the steel surface, is comprehensively elucidated via density functional theory (DFT) in s-CO2 systems at varied temperatures. The findings from this study offer valuable insights into mitigating corrosion-related challenges in s-CO2 system.

Bis(dimethylpyrazolyl)-aniline-s-triazine derivatives as efficient corrosion inhibitors for C-steel and computational studies.

4,6-Bis(3,5-dimethyl-1H-pyrazol-1-yl)-N-phenyl-1,3,5-triazin-2-amine (PTA-1), N-(4-bromophenyl)-4,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)-1,3,5-triazin-2-amine (PTA-2) and 4,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)-N-(4-methoxyphenyl)-1,3,5-triazin-2-amine (PTA-3) were synthesized and characterized. Their corrosion inhibition of carbon C-steel in 0.25 M H2SO4 was studied by electrochemical impedance. The inhibition efficiency (IE%) of triazine was superior due to the cumulative inhibition of triazine core structure and pyrazole motif. Potentiodynamic polarizations suggested that s-triazine derivatives behave as mixed type inhibitors. The IE% values were 96.5% and 93.4% at 120 ppm for inhibitor PTA-2 and PTA-3 bearing -Br and -OCH3 groups on aniline, respectively. While PTA-1 without an electron donating group showed only 79.0% inhibition at 175 ppm. The adsorption of triazine derivatives followed Langmuir and Frumkin models. The values of adsorption equilibrium constant K°ads and free energy change ΔG°ads revealed that adsorption of inhibitor onto steel surface was favoured. A corrosion inhibition mechanism was proposed suggesting the presence of physical and chemical interactions. Density functional theory computational investigation corroborated nicely with the experimental results. Monte Carlo simulation revealed that the energy associated with the metal/adsorbate arrangement dE ads/dN i, for both forms of PTA-2 and PTA-3 with electron donating groups (-439.73 and -436.62 kcal mol-1) is higher than that of PTA-1 molecule (-428.73 kcal mol-1). This aligned with experimental inhibition efficiency results.

Solvent selection and studies of the anti-corrosion efficacy of Heliotropium curassavicum leaves extract on API L X60 steel in 5 wt% hydrochloric acid solution

Corrosion is a huge challenge in the manufacturing industry during sticky oxides, grease, and rust removal from metal surfaces. It is often managed by the use of inhibitors and current interest is on sustainable inhibitors with less to zero harmful effects. This study explores the efficacy of Heliotropium curassavicum leaves extracts (HCLEs) in retarding the deterioration of API X60 grade steel in 5 wt% HCl solution and the influence of extracting solvent namely acetone (ACE), ethanol (ETH), water (WAT), butanol (BUT), methanol (MET), isopropanol (ISO), and ethyl acetate (ETA) on performance. The characterization of the HCLEs was achieved by Fourier-transform infrared (FTIR) and ultraviolet–visible (UV–vis) spectroscopies while the weight loss, electrochemical, and surface examination approaches were used for anticorrosion property evaluation. The results disclose that irrespective of extracting solvent, the extracts could suppress the dissolution of the substrate under the studied conditions. The best performance is, however, noted for ethanolic HCLE where 300 mg/L protected the substrate surface by 51.46% at 25 °C. Hence, ethanolic HCLE was selected for detailed studies and results indicate that the steel surface can be protected by 78.42% if 1000 mg/L of extract is used. Furthermore, the performance of the extract improves upon an increase in the temperature of the corrodent. The findings suggest that ethanolic HCLE could be considered for material protection during HCl pickling.

Microstructure regulation and performance of titanium alloy coating with Ni interlayer on the surface of mild steel by laser cladding

The preparation of Ti-alloy coating on the steel surface via laser cladding is very easy to form Fe-Ti phase and large tensile residual stress, which is not conducive to the performance of Ti-alloy coating. Here, Ti-6Al-4V coating (TC4-coating) was prepared on the mild steel substrate using laser cladding technology with Ni-alloy as the interlayer, and the Fe-Ti phase inside was completely suppressed. Increasing the powder feeding rate and scanning speed can change the undercooling of the alloy melt and the preferred growth orientation of the grains, while limiting the abnormal grain growth and grain boundary segregation, which is beneficial for grain refinement and equiaxed crystal formation. Reducing the scanning speed and powder feeding rate can increase the molten pool lifetime, thereby increasing the dilution rate of the coating and facilitating the formation of Ti2Ni phase. The abundant Ti2Ni inside the coating gives the TC4-coating greater microhardness (>500 HV0.1) and better corrosion resistance (Icorr of 7.00 × 10−8 A·cm−2). Grain refinement of the coating texture caused by the increase of powder feeding rate and scanning speed, as well as the high content of β-Ti phase and martensite structure, can improve the adhesion and shear strength of TC4-coating (386 ± 31 MPa).

Double-layered composite coating with enhanced self-healing and anti-corrosion performance based on synergistic effect of l-methionine and vanillin

Nanocontainers loaded with corrosion inhibitors as fillers can endow the organic coating with self-healing abilities. However, the number of nanocontainers that can be added to the coating is limited, and the number of corrosion inhibitors that can be accommodated by the nanocontainers is also limited. These considerably mitigate the anti-corrosion properties of the self-healing coating. Herein, a self-healing double-layered composite coating (MK-VK/EP), l-methionine (L-met)-loaded dendritic silica (KCC-1) nanocontainers modified epoxy coating (EP) as the bottom layer (MK/EP) and vanillin (Van)-loaded KCC-1 modified EP as the top layer (VK/EP), was fabricated on the surface of carbon steel. The results of electrochemical impedance spectroscopy (EIS) show that the low frequency impedance modulus (|Z|0.01Hz) of MK-VK/EP is nearly two orders of magnitude higher than that of MK/EP or VK/EP in 3.5 wt% NaCl solution after 45 days. Furthermore, the self-healing rate (rself-healing) of the scratched MK-VK/EP coating (S-MK-VK/EP) is still much higher than that of the scratched MK/EP or VK/EP in the last two stages of immersion. Meanwhile, there exists no apparent corrosion after 12 h of immersion from the optical image of S-MK-VK/EP. The results show that MK-VK/EP can provide better self-healing corrosion protection performance than the single coating (MK/EP or VK/EP). Hence, the synergistic effect of different corrosion inhibitors can greatly improve anti-corrosion abilities of the coating, which will provide an effective approach for corrosion protection of metal in marine environment.