Atmospheric Corrosion Of Mild Steel Research Articles

Inhibition for atmospheric corrosion of mild steel by lysine salts with graphene oxide interlayer in situ modulation

In this paper, an environmentally friendly volatile corrosion inhibitor, lysine salts (LA), was prepared between graphene oxide (GO) layers by in situ intercalation technique and its corrosion inhibition effect was evaluated. The results indicated that the pore structure of GO facilitated the dispersion of LA molecules and improved the volatility. LA-GO2 achieved a 99.3% corrosion inhibition efficiency after composition optimization, mainly due to its significant inhibition of the electrochemical anodic process on the surface of mild steel. Moreover, the properties of the surface film on the corroded steel were also characterized in detail to reveal the corrosion inhibition mechanism of LA-GO2.

Investigation on the initial atmospheric corrosion of mild steel in a simulated environment of industrial coastland by thin electrical resistance and electrochemical sensors

The initial corrosion behaviour of carbon steel in a simulated industrial coastland atmosphere was in-situ monitored by thin electrical resistance (TER) and electrochemical impedance spectrum (EIS) sensors through cyclic wetting and drying test. In contrast to the deposition of NaCl particles, the corrosion of (NH4)2SO4 deposition on carbon steel is totally unique, where the thickness loss of NaCl-contaminated carbon steel presents an “up-ramp” increase, but that of (NH4)2SO4-contaminated shows a sharp increase in the first cycle but a “flat” increase in the subsequent cycles regardless of the (NH4)2SO4 loading density, and the corrosion rate of carbon steel versus the loading density of (NH4)2SO4 presents a power function relationship. Moreover, the thickness loss of carbon steel under mixed NaCl-(NH4)2SO4 particles is higher than that under any lone salt deposition with the same loading density. A higher NaCl ratio in the mixed salts leads to a more serious corrosion loss, indicating that the mixed salts have a synergistic deterioration effect on the corrosion of carbon steel, suggesting that the Cl- ions can destroy the corrosion product layer formed by (NH4)2SO4 particles. Finally, the corrosion loss of carbon steel contaminated by mixed salt obeys a typical power function law against time.

Potential of Tomato Pomace Extract as a Multifunction Inhibitor Corrosion of Mild Steel

The aim of this paper is to investigate tomato pomace extract (TPE) as a multifunctional “green” vapor phase corrosion inhibitor for prevention from the atmospheric corrosion of mild steel and as a corrosion inhibitor in neutral media of 0.5 M NaCl solution. TPE would be an effective inhibitor with the efficiency of around 98% in both corrosive conditions. The chemical profile of the TPE was analyzed using gas chromatography mass spectrometry (GC–MS) and high-performance liquid chromatography analysis (HPLC-DAD-MS). The major volatile constituents identified in tomato pomace extract were alcohols (12.5%), fatty acids (23.78%), aldehydes (41.6%), ketones (8.65%), and terpenoids (9.11%). The predominant semi-volatile and high molecular weight chemical components in tomato pomace extract were phenolic acids and flavanols [caffeic acid (2.03 ± 0.3 μg/g), chlorogenic acid (37.23 ± 0.80 μg/g), gallic acid (10.2 ± 0.80 μg/g)]. The corrosion protection properties of the TPE as multifunctional corrosion inhibitor were studied using accelerated corrosion tests (weight loss method) and electrochemical methods [polarization curves and linear polarization technique (LPR)]. The mechanism of steel inhibition by TPE formulations was studied with the help of scanning electron microscopy (SEM) and atomic force microscopy (AFM) observations. TPE acts as a "pro-inhibitor" of the steel corrosion in neutral solution. The analysis confirmed that the growth of inhibitory properties is prolonged and corrosion rate is reduced after 40–48 h of exposure. The inhibition efficiency increases with increasing exposure time and reaches 98% after 48 h. Quantum-chemical calculations were used to predict the adsorption/inhibition properties of some of the main compounds of the extract and compounds formed as a result of chemical conversion. This work to contributes interpretation/explanation and understanding of the mechanism of action of green corrosion inhibitors in neutral solution.

Investigation on the Initial Atmospheric Corrosion of Mild Steel in a Simulated Environment of Industrial Coastland by Thin Electrical Resistance and Electrochemical Sensors

Investigation on the Initial Atmospheric Corrosion of Mild Steel in a Simulated Environment of Industrial Coastland by Thin Electrical Resistance and Electrochemical Sensors

Wavelet Analysis of Electrochemical Noise Measurements During Atmospheric Corrosion of Mild Steel in the Simulated Marine Environment

Wavelet Analysis of Electrochemical Noise Measurements During Atmospheric Corrosion of Mild Steel in the Simulated Marine Environment

Electrochemical, Spectroscopic and Quantum Chemical Calculation Studies on Some Quinoxaline Derivatives As Corrosion Inhibitors for Mild Steel in Hydrochloric Acid Medium

Mild steel is considered a material of choice in diverse industrial and structural applications. It is used to make a wide range of equipment due to its relatively low cost and good mechanical strength [1]. But acid solutions used in many industrial processes such as acid cleaning and oil well acidizing constitute strong corrosion media that enhance the rate of mild steel corrosion. As a result, corrosion of steel has been identified as a common problem that consumes large maintenance costs in many industries. It has been established that organic molecules containing heteroatoms such as nitrogen, oxygen and sulphur usually exhibit good anticorrosion activities [2]. Quinoxaline and its derivatives are among organic compounds that have been reported to be good corrosion inhibitors [3]. Quinoxaline units are parts of many materials including dyes and pharmaceuticals. They are biodegradable and non-toxic. Thus, the purpose of this work is to investigate the corrosion inhibition activities of some quinoxaline derivatives on the corrosion of mild steel in hydrochloric acid medium. To the best of our knowledge, the set of organic compounds selected for this work has not been investigated for the same purpose in any previous work. In this study, the corrosion inhibition and adsorption characteristics of four quinoxaline derivatives (Me-4-PQPB, Mt-3-PQPB, Mt-4-PQPB and Oxo-1,3-PQPB) on mild steel surface in 1 M HCl were investigated. Potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) techniques were used in the study. Fourier transform infrared (FTIR) and ultraviolet-visible (UV-Vis) spectroscopic techniques were used to investigate possible formation of Fe/inhibitor complex and/or adsorption of the inhibitors on steel surface. Quantum chemical calculations were carried out on the molecules to correlate experimental results with quantum molecular parameters. The results showed that the studied molecules inhibit corrosion of mild steel in HCl medium with Me-4-PQPB having the best inhibition property. The inhibitors are mixed-type in their activities. All the inhibitors physisorb and chemisorb spontaneously on mild steel surface and their adsorption behaviour obeyed Langmuir equation. Some quantum chemical parameters support the observed trend of inhibition potencies and suggest that the inhibition effects were attributed to the protonated forms of the quinoxaline derivatives. The graphical surfaces of condensed Fukui indices suggest possible adsorption sites on the inhibitors. References De la Fuente D., Diaz I., Simancas J., Chico B., Morcillo M. “Long-term Atmospheric Corrosion of Mild Steel, Corrosion Science (2010), doi:10.1016/j.corsci.2010.10.007.Obi-Egbedi N.O., Obot I.B., El-Khaiary M.I., Umoren S.A., Ebenso E.E. “Computational Simulation and Statistical Analysis on the Relationship between Corrosion Inhibition Efficiency and Molecular Structure of Some Phenanthroline Derivatives on Mild Steel Surface.” Int. J. Electrochem. Sci., 6 (2011): 5649 – 5675. Obi-Egbedi, N.O. and Obot, I.B. Indeno-1-one-[2,3-b]-quinoxaline as an effective inhibitor for the corrosion of mild steel in 0.5M H2SO4 solution. Materials Chemistry and Physics 122 (2010) 325–328.

Airborne chloride deposit and its effect on marine atmospheric corrosion of mild steel

Research has been carried out for one year in six pure marine atmospheres with annual average chloride deposition rates of 70–1906mg Cl−/m2 day. A study of some environmental parameters and their influence in the airborne chloride deposit on the site has been accomplished. The paper also considers mild steel corrosion rate and the resulting corrosion products and layers, and its dependence of atmospheric salinity of the site. In addition to lepidocrocite and goethite, high akaganeite and magnetite contents were found in the corrosion products. Additional magnetite formation is possible due to the transformation of lepidocrocite.

Kinetics of atmospheric corrosion of mild steel in marine and rural environments

In continuation of the extensive studies carried out to update the corrosion map of India, in this study, the degradation of mild steel by air pollutants was studied at 16 different locations from Nagore to Ammanichatram along the east coast of Tamilnadu, India over a period of two years. The weight loss study showed that the mild steel corrosion was more at Nagapattinam site, when compared to Ammanichatram and Maravakadu sites. A linear regression analysis of the experimental data was attempted to predict the mechanism of the corrosion. The composition of the corrosion products formed on the mild steel surfaces was identified by XRD technique. The corrosion rate values obtained are discussed in the light of the weathering parameters, atmospheric pollutants such as salt content & SO2 levels in the atmosphere, corrosion products formed on the mild steel surfaces.

A brief review on the atmospheric corrosion of mild steel in Iran

AbstractThis paper presents a review on the atmospheric corrosion of steel, at three sites, in Iran. Corrosion rate values, time of wetness, and the level of pollutants, namely of SO2 and chlorides were determined for the first year of exposure in order to establish the aggressiveness of the atmospheres. The results obeyed well with the empirical kinetics equation of the form C = Ktn.

Atmospheric corrosion of mild steel in chloride-rich environments. Questions to be answered

This paper describes the peculiarities of carbon steel corrosion in very severe marine atmospheres and points out a number of uncertainties that still need to be explained, such as the following: (a) Data on the evolution of carbon steel corrosion (C) with exposure time (t) obeys the power function C = Atn. The variables upon which n depends are not fully known, though the salinity of the atmosphere undoubtedly plays a prominent role. (b) In marine atmospheres, the presence of akaganeite and magnetite phases among the corrosion products is especially significant. In relation with these corrosion products, a number of important questions remain unanswered: What conditions are necessary for their formation? Where are they preferentially located? Is there a critical atmospheric salinity concentration below they are unlikely to form? It is also of great interest to know the typical surface microscopic morphologies resulting from the presence of akaganeite, where the confusion among researchers is well known. (c) In very severe marine atmospheres, the morphology of the corrosion layers formed on steel can be highly unusual, such as sheet-type or mound rust. There is a lack of basic knowledge on the formation mechanisms and internal microstructure of these rust types.

Effect of Relative Humidity on Corrosion of Steel under Sea Salt Aerosol Proxies: I. NaCl

This paper is the first of two that examine the relationship between relative humidity, the hygroscopic behavior of sea salt aerosol proxies, and the atmospheric corrosion of mild steel contaminated with them. Here, the association between the deliquescence phase transitions (solid-aqueous) of a single salt, NaCl, and the corrosion response of steel contaminated with this salt is examined. Specific focus is given to mechanisms that allow corrosion below the deliquescence relative humidity of NaCl (76% RH). Mild steel loaded with aqueous NaCl drops or crystals (9 μg·cm−2) was subjected to isohumidity exposures for up to 300 days. The resulting damage was quantified by optical profilometry. The corrosion chemistry that developed was identified using EDS and Raman spectroscopy. The wetting and drying of simulated corrosion chemistries were characterized by impedance measurements across an interdigitated electrode sensor. Taken together, these results show that corrosion can initiate by adsorbed water on NaCl crystals at as low as 33% RH. At 53% RH and above, attack proceeded at rates comparable to that observed above the deliquescence RH due to the development of hygroscopic corrosion chemistry. The governing role of the hygroscopic properties of this chemistry on attack rate and morphology is discussed.

Effect of Relative Humidity on Corrosion of Steel under Sea Salt Aerosol Proxies: II. MgCl2, Artificial Seawater

This paper is the second of two that examines between the hygroscopic behavior of sea salt aerosol proxies and the atmospheric corrosion of mild steel contaminated with them. In this work, artificial seawater (ASW) and MgCl2 were examined. The wetting and drying behavior of ASW was characterized by impedance measurements across an interdigitated electrode sensor. Steel coupons loaded with ASW and MgCl2 microparticles were subjected to isohumidity exposures for up to 30 days. The resulting damage was quantified by optical profilometry. The corrosion chemistry that developed was identified using EDS and Raman spectroscopy. Together, the results bring into question whether sea salt-contaminated surfaces ever dry in ambient outdoor environments. Sustained corrosion was detectable down to 11% RH for MgCl2 and 23% RH for ASW, with significant admittance of ASW deposits at <2% RH after 24 h, likely due to fluid trapping under a solid salt crust. Trends in corrosion loss versus RH were not directly reflective of the major liquid-solid phase transitions observed or predicted for ASW or MgCl2 alone. In light of this, common time of wetness determination methods are contended to be fundamentally flawed as quantitative indicators of electrolyte presence and the potential for significant corrosion.

Inhibition of Atmospheric Corrosion of Mild Steel by New Green Inhibitors under Vapour Phase Condition

Inhibition of Atmospheric Corrosion of Mild Steel by New Green Inhibitors under Vapour Phase Condition

Atmospheric corrosion of mild steel

The atmospheric corrosion of mild steel is an extensive topic that has been studied by many authors in different regions throughout the world. This compilation paper incorporates relevant publications on the subject, in particular about the nature of atmospheric corrosion products, mechanisms of atmospheric corrosion and kinetics of the atmospheric corrosion process, paying special attention to two matters upon which relatively less information has been published: a) the morphology of steel corrosion products and corrosion product layers; and b) long-term atmospheric corrosion ( > 10 years).

Long-term atmospheric corrosion of mild steel

A great deal of information is available on the atmospheric corrosion of mild steel in the short, mid and even long term, but studies of the structure and morphology of corrosion layers are less abundant and generally deal with those formed in just a few years. The present study assesses the structure and morphology of corrosion product layers formed on mild steel after 13 years of exposure in five Spanish atmospheres of different types: rural, urban, industrial and marine (mild and severe). The corrosion layers have been characterised by X-ray diffraction (XRD) and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Long-term corrosion is seen to be more severe in the industrial and marine atmospheres, and less so in the rural and urban atmospheres. In all cases the corrosion rate is seen to decrease with exposure time, stabilising after the first 4–6 years of exposure. The most relevant aspects to be noted are (a) the great compaction of the rust layers formed in the rural and urban atmospheres, (b) the formation of hematite and ferrihydrite phases (not commonly found) in the industrial and marine atmospheres, respectively and (c) identification of the typical morphological structures of lepidocrocite (sandy crystals and flowery plates), goethite (cotton balls structures) and akaganeite (cotton balls structures and cigar-shaped crystals).

Atmospheric corrosion of mild steel in the Niger Delta region of Nigeria. Part 1: Characterization of the Calabar, Cross River State environment

The atmospheric corrosion of Calabar, Cross River State environment has been investigated for 12 months using weight loss technique. The extent of pollution of the environment was also determined via measurements of the precipitation and air quality parameters. Apart from the suspended particulate matter (SPM) (113-630 &mu;g/m3) and NO2 (> 0.06 ppm) values, other measured atmospheric parameters (CO < 9.2 ppm, NH3 < 4.3 ppm and SO2 < 0.380 ppm) and precipitation parameters (pH > 5.0, conductivity < 60 &mu;Scm-1, TDS < 41.48 mg/l, TSS < 0.05 mg/l, NO3 - < 3.00 mg/l, SO4 2-

Polyamine compound as a volatile corrosion inhibitor for atmospheric corrosion of mild steel*

AbstractBis‐piperidiniummethyl‐urea (BPMU) was developed as a volatile corrosion inhibitor (VCI) for mild steel. Its vapor corrosion inhibition property was evaluated by volatile inhibiting sieve test (VIS). Electrochemical measurements were conducted in simulated atmospheric corrosion water. Electrochemical impedance spectroscopy of a volatile corrosion inhibitor monitor cell (VCIM) was applied to study the effect of BPMU on the corrosion inhibition of mild steel under a thin electrolyte layer. The results show that BPMU has good protection effect for steel. It suppressed the anodic reaction of the steel electrode in a manner of promoted passivation. Fourier transform infrared (FT‐IR) spectroscopy was used to characterize the adsorption of BPMU on the steel surface.

Investigation of atmospheric corrosion of mild steel after treatment by several inhibitor solutions

Atmospheric corrosion is a common problem in the Gulf region in Saudi Arabia. Steel products produced locally have a problem of discoloration when stored in stockyards due to atmospheric corrosion. Corrosion inhibition of mild steel in the industrial and marine atmosphere of the Arabian Gulf region was investigated in this study. Sodium dihydrogen orthophosphate, dicyclohexylamine nitrite and sodium benzoate were used as inhibitors of the investigation. The three inhibitors were evaluated under atmospheric conditions by weight loss measurements and electrochemical techniques in a simulated solution of 2·0%NaCl and 1·0%Na2SO4. Sodium dihydrogen orthophosphate had the best performance among the three inhibitors. It was still effective at the end of 180 days of atmospheric exposure. The performances of dicyclohexylamine nitrite and sodium benzoate, on the other hand, were effective in the early stages of the atmospheric exposure (for ∼2 months). Their inhibition effectiveness deteriorated with further exposure to the atmosphere, being totally ineffective by the end of the exposure period.

Atmospheric corrosion of mild steel in Oman

A systematic study has been made of the initial corrosion products which form on mild steel capons exposed near the coastal region of Oman and at some industrial areas. The phases and compositions of the products formed at different periods of exposure were examined by using Mossbauer spectroscopy (295 and 78 K) and X-ray diffraction (XRD) techniques. The results show that lepidocorcite and maghemite are early corrosion products and goethite starts to form after 2 months of metal exposure to the atmosphere. Akaganeite is an early corrosion product but it forms in marine environments only, which reflects the role of chlorine effect in the atmosphere. The 12 months coupons showed the presence of goethite, lepidocorcite and maghemite, but no akaganeite being seen in the products of one of the studied areas.

Kinetics of atmospheric corrosion of mild steel, zinc, galvanized iron and aluminium at 10 exposure stations in India

As a part of updating Corrosion Map of India project, atmospheric corrosion behaviour of commercially available engineering materials such as mild steel, galvanized iron, zinc and aluminium metals was studied in marine, industrial, urban, and rural environments by weight loss method at 10 exposure stations in India over a period of 5 years. The results of these studies demonstrated that galvanized iron, zinc and aluminium metals were several times more durable than mild steel. Compared to galvanized iron and zinc, aluminium provided superior protection in industrial and marine environment except at Mormugao Port Trust (MPT). It also offered much better resistance to corrosion in rural environments. At certain places, galvanized iron proved to be more durable than aluminium. The results obeyed well with the empirical kinetics equation of the form C = Kt n , where K and C are the corrosion losses in μm after 1 and ‘ t’ years of the exposure, respectively, and ‘ n’ is a constant. Based on ‘ n’ values, the corrosion mechanisms of these metals are predicted. The corrosion products formed on the metal samples in Chennai marine atmosphere were identified by X-ray diffraction analysis.