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The paper aims to report an experimental investigation of the effectiveness of an alkyl amine‐based inhibitor on the corrosion behavior of 1018 carbon steel in sea water. The adsorption equilibrium for this corrosion inhibitor on carbon steel was also investigated. The corrosion inhibitor was evaluated based on parameters such as inhibitor concentration, temperature, stirring speed and pH.

The experimental setup employed an autoclave with a flow circulation system. Weight loss determinations and electrochemical techniques such as polarization resistance and potentiodynamic polarization were used to detect and monitor the performance of the corrosion inhibitor. Surface examination of the steel substrate before and after applying different doses of inhibitor was undertaken using Fourier transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS).

Inhibition efficiency was enhanced by adsorption of amine‐containing functional groups on the steel surface. This adsorption capacity was measured and fitted Langmuir and Shawabkeh‐Tutunji isotherms and was found to require a maximum requirement of 1.08 mg of corrosion inhibitor to provide a monolayer of cover on the carbon steel surface. The inhibition efficiency increased with increasing the inhibitor concentration and solution pH. Moreover, increasing the solution temperature and stirring speed had an adverse effect on inhibition efficiency. Polarization data fitted by the Butler‐Volmer Equation showed the values of anodic and cathodic Tafel coefficients were an average of 0.8 and 0.2, respectively. The measured corrosion rates decreased rapidly within the first hour after commencing the experiments, which is related to the formation of a protective oxide film.

More inhibitor concentrations can be studied in order to draw more comprehensive conclusions on the efficiency of the tested inhibitor.

The effect of alkyl amine‐based inhibitor on the corrosion inhibition characteristic of 1018 carbon steel (CS) in sea water was determined at different inhibitor concentrations, temperatures, stirring speeds and pH.

The new information reported in this paper is the effect of alkyl amine‐based inhibitor on the corrosion characteristics of 1018 carbon steel in seawater using an autoclave with a flow circulation system. The paper is valuable to researchers in the area of corrosion inhibitors and oil and gas industry.

The purpose of this paper is to study the corrosion inhibition of carbon steel (CS) using a “green” inhibitor, polyvinyl pyrrolidone (PVP), in an aerated, alkaline medium containing 0.1M NaCl (blank) at pH 9 and pH 10. The effects of some additives, such as KI and untreated Saudi clay (UC) were investigated.

Weight loss method, surface studies, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarisation were applied.

The inhibition efficiencies of blank solutions with 1000 ppm PVP ranged from 66‐78% for weight loss results and from 23‐66% for the electrochemical tests. The EIS results indicated that the adsorption of PVP led to the formation of a protective film on the metal/solution interface. Tafel results indicated that PVP is a mixed‐type inhibitor. The addition of KI to PVP and the blank solution significantly increased inhibition efficiency, while the addition of UC reduced the inhibition efficiency. Adding KI resulted in a high surface‐area coverage ranging from about 91% after one hour to about 81% after 45 hours. The adsorption mechanism was fitted with a Langmuir isotherm.

This is a static study, whereas in oil drilling there is a dynamic system; however the findings may apply to both systems.

Carbon steel is used in alkaline and neutral media in the petroleum industry. The effect of KI additives was examined.

The paper shows how it may be possible to reduce the cost of repair of equipment and lower the environmental impact of corrosion.

There are few studies which investigate the combining effect of polymer and KI in alkaline medium containing NaCl.

This study aims to achieve long-term prediction on a specific monotonic data series of atmospheric corrosion rate vs time.

This paper presents a new method, used to the collected corrosion data of carbon steel provided by the China Gateway to Corrosion and Protection, that combines non-linear gray Bernoulli model (NGBM(1,1) with genetic algorithm to attain the purpose of this study.

Results of the experiments showed that the present study’s method is more accurate than other algorithms. In particular, the mean absolute percentage error (MAPE) and the root mean square error (RMSE) of the proposed method in data sets are 9.15 per cent and 1.23 µm/a, respectively. Furthermore, this study illustrates that model parameter can be used to evaluate the similarity of curve tendency between two carbon steel data sets.

Corrosion data are part of a typical small-sample data set, and these also belong to a gray system because corrosion has a clear outcome and an uncertainly occurrence mechanism. In this work, a new gray forecast model was proposed to achieve the goal of long-term prediction of carbon steel in China.

The purpose of this paper is study of the type of functional group and its situation on phenyl molecule, in increasing the corrosion protection of modified graphene layers by it. Corrosion protection efficiency of graphene was raised via modifying the surface of graphene-coated carbon steel (CS/G) by using aromatic molecules. Phenyl groups with three different substitutions including COOH, NO₂ and CH₃ grafted to graphene via diazonium salt formation route, by using carboxy phenyl, nitro phenyl and methyl phenyl diazonium salts in ortho, meta and para spatial situations.

Molecular bindings were characterized by using X-ray diffractometer, fourier-transform infrared spectroscopy (FTIR), Raman and scanning electron microscopy (SEM)/ energy dispersive X-ray analysis (EDXA) methods. Anti-corrosion performance of modified CS/G electrodes was evaluated by weight loss and electrochemical techniques, potentiodynamic polarization (Tafel) and electrochemical impedance spectroscopy, in 3.5 per cent NaCl solution.

The obtained results confirmed covalently bonding of phenyl groups to the graphene surface. Also, the observed results showed that substitution spatial situations on phenyl groups can affect charge transfer resistance (R_ct), corrosion potential (E_corr), corrosion current density (j_corr) and the slope of the anodic and cathodic reaction (ß_a,c), demonstrating that the proposed modification method can hinder the corrosion reactions. The proposed modification led to restoring the graphene surface defects and consequently increasing its corrosion protection efficiency.

The obtained results from electrochemical methods proved that protection efficiency was observed in order COOH < NO₂ < CH₃ and MPD in the para spatial situation and showed the maximum protection efficiency of 98.6 per cent in comparison to other substitutions. Finally, the ability of proposed graphene surface modification route was further proofed by using surface methods, i.e. SEM and EDXA, and contact angles measurements.

This study presents a numerical modeling by the finite element method of galvanic corrosion between the bolt (cathode) and the end plate (anode). The bolt is made of three types of stainless steel: austenitic (SS304L, SS316L), martensitic (SS410, SS420) and duplex (32,101), and the end plate is made of carbon steel (S235JR).

Finite element modeling.

The results obtained show, on the one hand, that this corrosion rate increases as the conductivity increases, on the other hand, the stainless steels having the highest corrosion resistance causes a considerable loss of mass of the end plate and subsequently a decrease in the lifetime of the bolted joint.

The galvanic corrosion of beam to column bolted joint with end plate, used in steel structures, was studied in order to determine the corrosion rate of the end plate and subsequently to predict the total lifetime of the bolted joint.

This study aims to describe the effect of magnetic field (MF) on the corrosion rate of N-80 carbon steel [N-80 carbon steel (CS)] in concentrated (12.5 Wt.%, 3.8 M) hydrochloric acid (HCl) using gravimetric weight loss (WL) measurements and potentiodynamic polarization (PDP) in various conditions at ambient temperature.

The effects of MF intensity, magnetization time and elapsed time on corrosion rate (CR) reduction (η) were studied.

The experimental results show that pre-magnetization of HCl sharply decreases the corrosion rate of N-80 carbon steel (CS) in acid. The maximum η was found to be 94%. The surface of CS was analyzed with scanning electron microscope in normal and magnetized acid.

To the best of the authors’ knowledge, no studies have delved into the effects of magnetization on the corrosion rate of CS in concentrated HCl solutions. All of the previous research studies deal with an external MF that is applied on the reaction cell, but the magnetization of fluid before coming in contact with CS is investigated for the first time. In the present work, the influence of MF on the corrosion rate of CS in HCl is illustrated using gravimetric WL and PDP methods. The effects of MF intensity as well as period of magnetization and elapsed time were verified in more than 35 tests.

The main purpose of the present work is to introduce two new Schiff bases as corrosion inhibitors (CIs) for carbon steel (CS). The anti-corrosion performance of these Schiff bases having N and S heteroatoms in their structures was investigated and compared in 2 M HCl electrolyte. The inhibitory activity of these Schiff bases was also assessed.

Common electrochemical assays like potentiodynamic polarization and electrochemical impedance measurements were used to evaluate the ability of compounds in reduction of the rate of corrosion. Quantum chemical calculations (QCCs) were also used to examine the corrosion inhibitive and the process related to the electrical and structural characteristics of the molecules acting as CIs.

The electrochemical measurements indicate that both Schiff bases acted as the efficient CIs of CS in 2 M HCl electrolyte. The adsorption of the Schiff base on the surface of the CS caused the corrosion to be inhibited. The change of Gibbs energies indicated that both physical and chemical interactions are involved in the adsorption of NNS and SNS on CS surfaces. The predicted QCCs of the CIs neutral and positively charged versions were well-aligned with those obtained by electrochemical experiments.

Using electrochemical experiments and quantum chemical modelings, two new Schiff bases, N-2-((2-nitrophenyl)thio)phenyl)-1-(pyrrole-2-yl)methanimine (NNS) and N-2-((2-nitrophenyl)thio)phenyl)-1-(thiophen-2-yl)methanimine (SNS), were evaluated as anti-corrosion agents for CS in 2 M HCl electrolyte. The DFT calculations were considered to compute the quantum chemical parameters of the inhibitors.

The purpose of this investigation is to study the corrosion inhibition of carbon steel (CS) using a “green” inhibitor, Opuntia ficus-indica, in an aerated, 0.5 M H₂SO₄ solution at different concentrations and temperatures.

Weight loss determinations, surface studies, electrochemical impedance spectroscopy and potentiodynamic polarization were applied during the investigation.

It was observed that Opuntia ficus-indica extract can decrease the corrosion rate of CS, and its efficiency increases with increasing concentration up to 1,000 ppm and with time, but decreases with increasing the temperature from 25 to 600C. The inhibitory activity is due to the presence of phenolic compounds in its chemical structure.

The work was done under static conditions, whereas in acid cleaning conditions, there is a dynamic system. However, the findings may apply to both the systems.

CS is used in acidic environments in the acid cleaning industry.

Results of this work show that it is possible to reduce the cost of repair of equipment and the environmental impact of corrosion.

There are very few investigations on the study of Opuntia ficus-indica leaf extract as a green inhibitor in an acidic environment.

The purpose of this paper is to evaluate and compare the protective, anticorrosion behaviors and electrochemically synthesis of poly(2-chloroaniline) (PCANI) and poly(2-chloroaniline-co-aniline) P(CANI-co-ANI) films on thin zinc–iron plated carbon steel (CS).

Zinc–iron (ZnFe) alloy plating was successfully achieved on CS applying 3 mA constant current value. The PCANI and P(CANI-co-ANI) films on ZnFe-plated CS electrode were synthesized by cyclic voltammetry technique using monomer(s) containing 0.20 M sodium oxalate solution. The CS/ZnFe electrodes with and without PCANI or P(CANI-co-ANI) films were characterized using SEM and anodic linear sweep voltammograms. The anticorrosive behaviors of uncoated and coated electrodes were studied in 3.5 per cent NaCl solution by corrosion techniques which include open circuit potential measurements, the anodic polarization curves and alternative current electrochemical impedance spectroscopy (EIS) technique.

The protection efficiency values (E per cent) for CS/ZnFe, ZnCS/ZnFe/PCANI and CS/ZnFe/P(CANI-co-ANI) electrodes were calculated as 71.05, 84.53 and 92.79, respectively, after 168 h of immersion time. The results showed that P(CANI-co-ANI) coating on ZnFe-plated CS electrode exhibited higher corrosion resistance and provided better barrier property in comparison with PCANI coating and ZnFe alloy plating, in longer exposure time.

A number of reports on the synthesis and characterization of PANI have appeared in the literature during the past decade, but there is no such publication of PCANI. At the same time, the synthesis of PCANI onto the surface of metal alloy coating being the first of this kind, no such proceedings have been reported in the literature so far.

The purpose of this paper is to study the metal-Microbe interaction playing a crucial role in microbiologically influenced corrosion (MIC) and biofouling of materials in cooling water systems. Treatment regimens should be planned based on this understanding.

Attempts were made in the past decades to characterize and understand biofilm formation on important power plant structural materials such as carbon steel (CS), stainless steel (SS) and titanium in fresh water and in seawater to achieve better control of biofouling and minimize MIC problems.

This report presents the results of detailed studies on tuberculation-formed CS because of the action of iron-oxidizing bacteria and the effects of algae- and bacteria-dominated biofilms on the passivity of SS. The preferential adhesion of different bacterial species on SS under the influence of inclusions and sensitization was studied in the context of preferential corrosion of SS weldments due to microbial action. Detailed characterization of biofilms formed on titanium (the likely condenser material for fast breeder reactors) after exposure for two years in Kalpakkam coastal waters revealed intense biofouling and biomineralization of manganese even in chlorinated seawater. Studies on the effectiveness of conventional fouling control strategies were also evaluated.

The detailed studies of different metal/biofilm/microbe interactions demonstrated the physiological diversity of microbes in the biofilms that were formed on different materials, coupling their cooperative metabolic activities with consequent corrosion behaviour. These interactions could enhance either anodic or cathodic reactions and exploit metallurgical features that enhance biofilm formation and/or the capacity of microbes to mutate and overcome mitigation measures.