Corrosion Rate Of Steel Research Articles

Construction and Optimization of Corrosion Map in a Broad Region of Acidic Soil via Machine Learning

Machine learning has been widely applied to exploring the key affecting factors for metal corrosion in some local regions. However, there is a lack of systemic research and a practicable prediction model for metal corrosion in a broad region. In this paper, the corrosion map of Q235 steel in a broad region of acidic soils of Hunan province of Central China was constructed and optimized via field experiment and machine learning. Both the experimental and optimized corrosion maps confirmed that the corrosion rate of the steel decreased from the western to the eastern part of the province. The concentrations of pH, F−, Cl−, NO3−, HCO3−, K+, and Mg2+ were the key affecting factors in the broad region of acidic soils of the province. Among them, the contribution rate of the HCO3− concentration was higher than that of other factors. The optimization model based on the ordinary least squares could be used for the optimization of the corrosion map of steels in a broad region of acidic soils. The optimized corrosion map was a good alternative to the estimation methods for the corrosion rate of steel in soil.

MICROSTRUCTURE AND EROSION CORROSION PROPERTY OF CRNI ALLOYED COATING ON CARBON STEEL

In this study, CrNi alloyed coating was deposited on Q235 low carbon steel by arc-added glow plasma depositing technique in order to increase the corrosion resistance property. It was found that the CrNi alloyed coating was composed of face-centered cubic Cr0.7Ni2.9Fe0.36 phase. The EDS results indicated that 7.3 [Formula: see text] m coatings were prepared which was bonded metallurgically with the substrate. The salt spray corrosion test result showed that the corrosion product film of coating was dense while the corrosion film of carbon steel was multilayered in morphology. The corrosion product film of CrNi coating reduced the corrosion rate. However, the corrosion product of Q235 with loose multi-layer structure increased corrosion process. The erosion corrosion properties of carbon steel and coating were tested in NaCl solution with different flowing speed through electrochemical test methods. The erosion corrosion results showed that the corrosion rate of carbon steel was increased in flowing NaCl solution. The corrosion product of CrNi coating could protect inner material in NaCl solution at flowing speed of 2 m⋅s[Formula: see text] to 6 m⋅s[Formula: see text].

Effect of Mo on the Corrosion Resistance of Cr-Containing Steel in a Simulated Tropical Marine Atmospheric Environment

In this manuscript, the effect of Mo addition on the corrosion resistance of the low-alloy steel in a simulated tropical marine atmospheric environment has been studied through microstructure characterization, corrosion immersion experiments, electrochemical measurement, and a series of microscopic characterization methods. The results show that Mo has the ability to reduce the corrosion rate of low-alloy steel in a marine atmospheric environment, with a more pronounced reduction effect observed over longer corrosion periods. The addition of Mo enhances the corrosion product film’s compactness when coupled with Cr, subsequently improving corrosion resistance. Simultaneously, MoO42−, acting as a slow-release ion, can effectively suppress localized corrosion in low-alloy steel. The research findings can offer data support and a theoretical foundation for the design of low-alloy steels with enhanced corrosion resistance in a tropical marine atmospheric environment.

Effect of yeast extract on microbiologically influenced corrosion of X70 pipeline steel by Desulfovibrio bizertensis SY-1

Microbiologically influenced corrosion (MIC) is a complicated process that happens ubiquitously and quietly in many fields. As a useful nutritional ingredient in microbial culture media, yeast extract (YE) is a routinely added in the MIC field. However, how the YE participated in MIC is not fully clarified. In the present work, the effect of YE on the growth of sulfate reducing prokaryotes (SRP) Desulfovibrio bizertensis SY-1 and corrosion behavior of X70 pipeline steel were studied. It was found that the weight loss of steel coupons in sterile media was doubled when YE was removed from culture media. However, in the SRP assays without YE the number of planktonic cells decreased, but the attachment of bacteria on steel surfaces was enhanced significantly. Besides, the corrosion rate of steel in SRP assays increased fourfold after removing YE from culture media. MIC was not determined for assays with planktonic SRP but only for biofilm assays. The results confirm the effect of YE on D. bizertensis SY-1 growth and also the inhibitory role of YE on MIC.

Estimating galvanic corrosion rate of copper/steel couple by using remote earth mixed potential

AbstractCopper and steel are often electrically connected in industrial devices, which causes galvanic corrosion in environments. To ensure the safety of the devices, it is needed to assess the corrosion rate of galvanic couples. The galvanic current is often used to calculate the galvanic corrosion rate in theory, however, in the actual devices, the copper parts are generally coupled with the steel parts and it is difficult to separate them to measure the galvanic current between them, as well as to determine the galvanic corrosion rates for actual devices. In this paper, the galvanic couple mixed potential distribution and influencing factors including area ratios, polarization characteristics, and medium resistivity are studied by experiments and calculation. The mixed potential becomes stable with a certain distance from the surface of copper/steel couple and acts as remote earth mixed potential. Remote earth mixed potential is positively associated with galvanic corrosion rate. Based on the results of experiments and calculation, a method to estimate the galvanic corrosion rate of steel in copper/steel couple by using the remote earth mixed potential is proposed.

The CO2 corrosion behaviour of 25Mn2 and 2Cr steels under certain downhole condition

An economical 2Cr steel tubing was prepared for application in a certain downhole corrosion condition, and the CO2 corrosion behaviour was investigated by employing the 25Mn2 steel for comparative study. The corrosion films of the two steels under different corrosion conditions were analysed by optical microscope, scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). It is revealed that the corrosion rate of 25Mn2 steel at static solution is about 2.5 times higher than that at the dynamic solution with the flow velocity of 1 m/s, while the corrosion rate of 2Cr steel keeps almost the same. It is found that both steels show two layers of corrosion film at static corrosion, and the corrosion film is mainly composed of FeCO3, α-FeOOH and dotted Fe3C in the inner layer. It is inferred that carbon pickup phenomenon observed in the corrosion film is attributed to the formation of FeCO3, as well as may also be due to phenomenologically the reaction of Fe3C with carbonic acid.

Estimating the corrosion rate of stainless steel R-SUS304ULC in nitric acid media under concentrating operation

The amount of corrosion of the austenitic stainless steel was evaluated considering the changes in solution composition and boiling during actual concentration operations. Austenitic stainless steel R-SUS304ULC is the structural material of the highly radioactive liquid waste concentrator in Japanese spent fuel reprocessing plant, which treats highly corrosive nitric acid solutions during enrichment operations. The study results show that it is necessary to focus on nitric acid concentrations, oxidizing metal ion concentrations, and decompression boiling as factors that accelerate the corrosion rate of stainless steel because of cathodic reaction activation.

The Corrosion Behavior of Cnidoscolus aconitifolius (Chaya) Leaf Extract on Mild Steel in H2SO4 and Brine (NaCl Solution) Environments

The inhibition efficacies of extracts of Cnidoscolus aconitifolius (Chaya) leaves in the corrosion of mild steel were investigated in H2SO4, and NaCl media. Weight loss method was employed to determine corrosion rate. The ribbed mild steel rod was cut into forty (40) coupons, each measuring 16 mm (diameter) by 8 mm (length) and their initial weights taken and noted. Twenty (20) beakers containing 0.5M and 1.0M each of H2SO4 and NaCl solution separately with varying volumes of the extracts ranging from 5ml to 20ml were set up with four (4) coupons in each beaker fully immersed using nylon strings. The set up was allowed to stand for an exposure time of 672hrs with a coupon withdrawn from each beaker every 168 hours and processed using standard procedures before being reweighed using digital weighing balance. The weight difference for each coupon was obtained and used for corrosion rate calculation using the formula, CPR= K∆W/ρAt. Other corrosion parameters were also obtained using the relevant formulae: inhibition efficiency, IE%=(〖CR〗_c-〖CR〗_i)/〖CR〗_c ×100 and surface coverage, , θ=(〖CR〗_c-〖CR〗_i)/〖CR〗_c .The results obtained indicated that the normal corrosion rate profile for passivating metals was followed with the weight loss by the coupons being higher in the control media than those ones in the inhibited media. It was also observed that increase in volumes of these extracts from 5ml to 20ml decreased the corrosion rate of mild steel in the media. We found that in both media Cnidoscolus aconitifolius (Chaya) exhibited high inhibition efficiencies of 78.14% in H2SO4 and 64.15% in NaCl at extract concentration of 20 ml. Plots of the Langmuir adsorption isotherms suggest uniform surface covering of the adsorbent molecules at equilibrium state of the adsorbate–adsorbent system, with very strong adsorption forces. Based on these findings, the results suggest that Cnidoscolus aconitifolius (Chaya) leaves extract is a veritable green inhibitor for both acidic and salt media and can be a suitable alternative to the synthetic inhibitors widely used in the oil and gas industry.

Corrosion of stainless steels and corrosion protection strategies in the semiconductor manufacturing industry: a review

Abstract Stainless steels are used extensively in semiconductor manufacturing as chamber, structure component and gas delivery systems. The corrosion in the aggressive gas in the semiconductor manufacturing industry leads to particle release, contaminating wafers and limiting their application. Moisture content can accelerate the corrosion rate of stainless steel. In a high-temperature environment, the corrosion is determined by the synergistic effect of the vapour of the corrosion product and thermal ageing. To eliminate corrosion, lots of efforts have been performed and categorized into three aspects: (1) Material purification using innovating metallurgy techniques, especially vacuum induction melting (VIM) and vacuum arc remelting (VAR). The ultra-pure stainless steel minimizes the inclusion in stainless steel, suppressing the breakdown of the passive film. (2) Smoothing the surface by polishing; the polishing surface shows hydrophobic behaviour and decreases moisture absorption. (3) Applying surface and coating techniques against corrosion, including passivation treatment and electroplating/electroless Ni-based coating. Herein, the techniques mentioned above are reviewed, and the prospect and development of stainless steel in the semiconductor manufacturing industry are forecasted.

Ekstrak Daun Matoa (Pometia pinnata) sebagai Inhibitor Korosi Baja Karbon SS-304

Research has been carried out on inhibitors from matoa leaf extract to inhibit the corrosion rate of SS-304 carbon steel. The Matao leaf extract used as an inhibitor was immersed in a 1 M H2SO4 corrosive medium. To determine the effect of inhibitor concentration and immersion temperature on steel corrosion, various inhibitor concentrations were varied, namely 0%, 1%, 2%, and 3% bt, and temperature variations, namely samples also in XRD and SEM characterization. 35°C and 40°C. The corrosion rate test was carried out using the weight loss method. The increase in the corrosion rate is in line with the increase in sample weight loss. The most efficient inhibitor of matoa leaf extract was obtained at a concentration of 3% with an immersion temperature of 35°C, namely 0.09 mmpy. The XRD results showed that the maximum peaks produced FeC and FeNi crystals, followed by FeO crystals. SEM characterization also showed that samples without inhibitors were more corroded, and samples using 3% inhibitor concentrations were slightly corroded.

Corrosion Evolution mechanism of N80 tubing steel under supercritical CO2 and H2S environment

The corrosion evolution mechanism of N80 tubing steel in 8 MPa supercritical CO2 and 0.1 MPa H2S environment was investigated. The results show that although the corrosion rate of N80 steel decreases with the prolonged corrosion time, it still maintains a high level of about 1.06 mm/y after a long period of 360 h. As the corrosion progresses, the corrosion products change from FeS to a mixture of FeS and FeCO3. The corrosion form of N80 steel changes from uniform corrosion to localized corrosion. The origin credited for localized corrosion is the detachment of large particles of FeS in the early corrosion stage. A double-layer film consisting of an outer layer of FeS and an inner layer of FeCO3 forms in the area of corrosion pits after a prolonged period of corrosion, which provides protection for the substrate, thereby causing the decrease of localized corrosion rate of N80 steel.

Influence of temperature on corrosion behavior of N80 Steel in multiple thermal fluid environment

During offshore oil production, O2 could be introduced into the multiple thermal fluid, and the temperature of the wellbore can reach up to 200°C, which may result severe corrosion of tubing. However, the corrosion mechanism of downhole pipes in such aggressive environment remains unclear in the high-temperature and high-pressure CO2-O2-H2O mixed environment. Herein, we investigated the corrosion behaviour of N80 steel with different temperatures in CO2-O2-H2O environment. The influence of temperature on composition and structure of the corrosion product film of N80 steel was characterized by scanning electron microscope, energy-dispersive spectroscopy and X-ray diffraction. The results show that the corrosion rates of N80 steel performed a downward trend with the increase of the temperature, but it increased slightly at 180°C. The corrosion rate of N80 steel was up to 1.6 mm/y at 60°C, owing to the damage to corrosion product film by O2 and reduced its protection at lower temperature. As the temperature increased, the formation of Fe3O4 enhanced the protection of the inner corrosion product film, thereby greatly reducing the corrosion rate. However, the product of (FeCa)CO3 in the corrosion film completely lost its protection at 180°C, and the corrosion rate increased slightly to 0.84 mm/y. With the temperature increased to 240°C the corrosion rate of N80 steel reduced to 0.24 mm/y on account of the formation of dense and complete Fe3O4.

Analysis of Nickel and Chrome Plating Temperature on Corrosion Rate of Steel in Seawater Environment

This study investigates the effect of Nickel and Chrome plating on ST 40 steel on corrosion resistance in a seawater environment. Several temperature variations were carried out during the chrome plating process, precisely at room temperature and 40℃, with a processing time of 5 seconds each and a voltage of 5 Volts. The Nickel plating was conducted with predetermined variables obtained from the initial research to achieve the most optimal results, especially the thickness of the plating formed. This process involves a temperature setting of 40℃, a processing time of 10 and 30 minutes, and a voltage of 5 Volts. To evaluate the results of this study, the corrosion testing was carried out using seawater corrosion media from 2 different beaches with 2.98% and 3.18% NaCl concentrations. In addition, microstructure testing is also conducted to determine changes in the structure of the base material after undergoing plating, and an optical microscope can be used to determine the thickness of the Nickel and Chrome layers. With Chrome plating at 40℃, the corrosion rate decreases compared to uncoated material in various seawater environments. The results emphasize that the plating process with the correct treatment can improve the corrosion resistance of steel, especially in seawater environments.

CORROSION OF CARBON STEEL AND SOME OTHER METALS IN FRESH WATER OF HYDRAULIC STRUCTURES (HS)

Using the method of gravimetric and electrochemical measurements, the corrosion rate of St3 steel in the water basins of the Takhtakerpi and Shemkirchay hydroelectric power stations has been determined. To establish the expected corrosivity of water, the chemical composition and some physicochemical parameters of the above waters have been determined. As a result of long-term measurements carried out over one year, it has established that steel in the water basins of the Takhtakerpi and Shemkirchay hydroelectric power stations corrodes at a rate of 0.04 g/m2 h and (0.07÷0.08) g/m2 h, respectively. And in the atmosphere of these hydroelectric power plants, steel corrodes at a low rate, approximately an order of magnitude lower. Analysis of water taken from these hydroelectric power stations showed a very low content of corrosive ions, the concentration of which, especially in the Shemkirchay reservoir, corresponds to spring water. By taking polarization curves it has been established that the rate of steel corrosion is controlled by the concentration of dissolved oxygen in water

Effect of turbulent flow on the oxide properties of carbon steel in alkaline water

The purpose of this study is to investigate the changes in the morphology, chemical state, defect density, and impedance of oxides formed on SA 106 Gr.B carbon steel by turbulent water flow at the micro and atomic levels. A compact magnetite layer composed of multi-faceted particles is formed in stagnant water, while a porous magnetite layer composed of particles without a certain shape is formed in turbulent water. Ferrous ions are preferentially dissolved from the oxide in turbulent water, which increases the vacancies in the oxide lattice. An increase in the concentration of point defects is shown to be comparable to an increase in the corrosion rate of carbon steel. The flow-accelerated corrosion behavior is also well correlated with the electrochemical impedance parameters including the charge transfer resistance and capacitance. Our study provides a further understanding of carbon steel corrosion under turbulent water flow conditions.

Innovations in nanomaterials: A paradigm shift in surface engineering for corrosion mitigation

The weight loss technique was utilized to examine the corrosion rates of mild steel in various aqueous solutions and operating conditions, both with and without an epoxy coating. It became out that the presence of salt and temperature increased the rate of corrosion while the pH level decreased. Significant reductions in corrosion rates occur in acidic conditions when coatings are present. In a saline solution, it did not work particularly well. Using X-ray diffraction, the diagnosis was acquired after a sol–gel method was used to create a MgO nanoparticle. The highest coating efficacy in an acidic solution was 96.9%, whereas the lowest coating efficacy in a saline solution devoid of nanoparticles was 29.8%. The performance of epoxy coatings in salty environments was improved by applying nanoscale magnesium oxide (MgO) up to a maximum value of 94%. Surface morphology was examined using the SEM test as well. A number of mathematical models were proposed to be employed in order to relate the corrosion rate to the operational state; a high correlation coefficient for the data advised that the polynomial interaction effect model be used.

A MIXTURE OF ACACIA BARK EXTRACT (Acacia mangium Willd) AND POTASSIUM IODIDE AS A CORROSION INHIBITOR IN SULFURIC ACID SOLUTION

Corrosion is a decrease in the quality of a metal material caused by a reaction with the environment. Corrosion cannot be eliminated, but corrosion can be slowed down in several ways by adding corrosion inhibitors and synergistic effects. Acacia bark extract (Acacia mangium Willd) with the addition of 0.02 M KI has the potential as a corrosion inhibitor for steel because it contains secondary metabolites, so it can provide a synergistic effect and increase the value of inhibition efficiency on steel. This research aimed to analyze the effect of a mixture of acacia bark extracts (Acacia mangium Willd) with the addition of KI on inhibition efficiency corrosion of mild steel in sulfuric acid media. The method used in this study is the method of weight loss, adsorption isotherms, and thermodynamic parameters, which were carried out by varying the concentration of acacia bark extract and the immersion temperature of the steel. To strengthen the research results, characterization was carried out using FTIR and SEM. The results showed that the corrosion rate of mild steel immersed in 0.75 M H2SO4 corrosive medium with the addition of 0.02 M KI increased with increasing immersion temperature. These results are reinforced by the results of FTIR and SEM analysis which show that there is an interaction between mild steel and acacia bark extract (Acacia mangium Willd) and KI 0.02 M. Based on the thermodynamic parameters, the resulting values of ∆Hads, ∆Gads, and ∆Sads show that the adsorption process of acacia bark extract (Acacia mangium Willd) in corrosive medium H2SO4 0.75 M with the addition of 0.02 M KI took place spontaneously, showing the type of physical adsorption, adsorbed stable, the adsorption process was exothermic and the degree of irregularity in the adsorption process. The inhibition efficiency of acacia bark extract (Acacia mangium Willd) with the addition of 0.02 M KI was highest at 60 °C with an extract concentration of 2.5 g/L of 81%. The higher the immersion temperature, the greater the resulting synergistic effect

Synergistic inhibitive effect of a hybrid zinc oxide-benzalkonium chloride composite on the corrosion of carbon steel in a sulfuric acidic solution

Abstract Zinc oxide and quaternary ammonium-type surfactants have been separately recognized for their anti-corrosive efficiencies. Their composite, not investigated so far, could provide a synergetic anti-corrosion effect. In this respect, the aim of this study is to synthesize a composite material consisting of zinc oxide and benzalkonium chloride (ZnO-BAC) in varying mass ratios (3:1, 1:1, and 1:3). The inhibitory properties of the ZnO-BAC composite against carbon steel corrosion in a 0.5 M sulfuric acid solution were assessed under ambient conditions. First, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy were used to examine the chemical structure of the prepared composite. Then, the corrosion inhibitive performance of the devised inhibitors was screened using electrochemical, hydrogen collection, and weight loss measurements. Further, the surface morphology was examined using a scanning electron microscope, both before and after immersion in the corrosion medium. The electrochemical measurements indicate that the prepared inhibitor exhibits a predominant cathodic inhibition behavior and the maximum inhibition efficiency, approximately 91.9%, was achieved for one-to-one mass ratio. Similar results were obtained from weight loss and hydrogen evolution measurements, which showed that the ZnO-BAC composite reduced the corrosion rate of carbon steel by 69.9% and 64.9%, respectively. Finally, molecular dynamics and an adsorption equilibrium model were used to elucidate the mechanism of corrosion inhibition by the ZnO-BAC composite, which exhibits a high adsorption energy on the iron surface.

Damage-Tolerant Wood Layers for Corrosion Protection of Metal Structures.

Mechanically strong and damage-tolerant corrosion protection layers are of great technological importance. However, corrosion protection layers with high modulus (>1.5 GPa) and tensile strength (>100 MPa) are rare. Here, we report that a 130 μm thick densified wood veneer with a Young's modulus of 34.49 GPa and tensile strength of 693 MPa exhibits both low diffusivity for metal ions and the ability of self-recovery from mechanical damage. Densified wood veneer is employed as an intermediate layer to render a mechanically strong corrosion protection structure, referred to as "wood corrosion protection structure", or WCPS. The corrosion rate of low-carbon steel protected by WCPS is reduced by 2 orders of magnitude than state-of-the-art corrosion protection layers during a salt spray test. The introduction of engineered wood veneer as a thin and mechanically strong material points to new directions of sustainable corrosion protection design.

Monitoring Atmospheric Corrosion of Carbon Steel Under Controlled Electrolyte Droplet Distributions

Field exposure testing and accelerated corrosion testing are two common approaches applied in the industry to assess the atmospheric corrosion rate of a specific material, both relying on visual inspection and weight change of the specimen. Field exposure testing occurs under natural atmospheric conditions but requires exposure times spanning decades, whereas accelerated corrosion testing shortens the exposure time to weeks; however, the connection between the natural environment and accelerated corrosion chamber conditions remains unresolved. Efforts have been made to correlate accelerated corrosion results with those obtained in field exposure based on weight loss, both qualitatively and quantitatively, primarily empirically and limited to small datasets.This work examines the link between modified field exposure testing and the environment from the electrolyte perspective, under controlled laboratory conditions. In-situ monitoring and analysis of corrosion rate, electrolyte condition, and environment are demonstrated to be feasible, and the effect of NaCl concentration and droplet distribution on the atmospheric corrosion rate of carbon steel has been addressed.This work proposes a setup wherein multiple droplet-based conditions are created, and corrosion kinetics are actively monitored using the electrical resistance method. The sample surface is simultaneously monitored with an optical microscope, through which both droplet distribution evolution and corrosion product formation can be visualized.