Corrosion Of Steel Research Articles

Corrosion Inhibitors for Carbon Steel in HCl Environment: Synthesis and Characterization of Trimethoprim-Metal Complexes

This study is about making and figuring out what trimethoprim (TM), a popular corrosion inhibitor, is like and then using it as an inhibiting agent to stop corrosion in carbon steel in acid media (HCl solution) through adsorption. TM has also been known as the prevalent anti-corrosive agent. It can be added to a liquid or gas to slow the pace of a chemical reaction (in the case of a material – typically a metal or alloy – that corrodes when it encounters the fluid). Many antibiotic compounds, such as TM derivatives, diiron salt dihydrate, and diiron salt tetrahydrate, have active groups that can stop metal from corroding. Spectroscopic methods like XRD (X-ray difraction), FTIR (Fourier transform infrared spectroscopy), UV-visible (ultraviolet-visible spectroscopy), and TGA (thermogravimetric analysis) were used to study the TM drug. Similarly, the OCP (open circuit voltage) technique was introduced to assess the corrosion resistance and the density of current vs. voltage. Finally, this study revealed that TM drugs could be suggested for introduction as corrosion inhibitors due to their simple production and the fact that they have many active groups that exhibit the ability to coordinate with carbon steel. Our study revealed that changes in inhibitor concentrations, the solution's acidity, and the metal's surface area all contribute to adsorption.

Corrosion Inhibition of Carbon Steel by Some Schiff Base Compounds in HCl and H2SO4 Solutions

AbstractThe inhibition power of two Schiff bases on carbon steel corrosion in 1 M HCl and 0.5 M H2SO4 solutions has been investigated using weight loss, Tafel polarization, and electrochemical impedance spectroscopy techniques. The results revealed that increasing the concentration of inhibitors in acidic solutions led to a higher inhibition efficiency. The polarization curves indicated that the Schiff bases acted as mixed inhibitors, affecting both the cathodic and anodic reactions. The adsorption of the inhibitors on the carbon steel surface followed the Langmuir adsorption isotherm, and various adsorption isotherm parameters such as Kads, ΔGads, ΔHads, and ΔSads were determined at room temperature. Furthermore, the effect of temperature on the inhibitors′ performance was examined within the range of 25–45 °C. The corrosion‐related activation energy, pre‐exponential factor (k), activation enthalpy, and entropy were calculated to assess the inhibitors′ behavior. Scanning electron microscopy (SEM) was employed to examine some carbon steel samples, revealing differences in inhibition efficiency attributed to the inhibitors′ chemical structure. The results highlighted the highest inhibition efficiency in H2SO4 medium at 93.4 %, with a corresponding free energy of 39.51 KJ/mol indicating physical‐chemical adsorption of inhibitor molecules. Furthermore, an enthalpy value of −40.6 KJ/mol suggested an exothermic inhibitor absorption process. The findings are presented and discussed in detail.

Atomic-Scale Insights into Flow-Accelerated Corrosion of Carbon Steel

The role of flow velocity on the formation and dissolution of oxides on SA106Gr.B carbon steel was investigated at both microscopic and atomic scales. In static water, a compact oxide layer with highly faceted magnetite particles was formed. Atomic-scale transmission electron microscopy images of such a layer revealed highly ordered and parallel lattice fringes, indicating that the oxide had very high crystallinity and minimal lattice defects. In contrast, turbulent water prompted the creation of a porous oxide layer consisting of amorphous magnetite particles. Here, numerous mismatched lattice fringes were observed, indicating a prevalence of point defects within the oxide structure. These differences in oxide properties are attributed to hydrodynamic shear stress induced by turbulent flow. These findings provide atomic-level insights into how carbon steel corrosion accelerates in fast-flowing water.

The Role of Rare Earths on Steel and Rare Earth Steel Corrosion Mechanism of Research Progress

Corrosion has always been an important factor affecting the life of steel, which causes huge economic losses every year. How to improve the corrosion resistance of steel has always been a research focus. Adding rare earth elements into steel is an important method to improve the corrosion resistance of steel. In this paper, the effects of rare earth elements on steel are summarized, including the purification of molten steel, modification and modification of inclusions, improvement of grain boundaries by solid solution strengthening, the influence of phase transformation and the refinement of microstructure, and reduction in C and N desolubilization. On this basis, the progress of research on the corrosion resistance mechanisms of rare earth steel is summarized, focusing on rare earth-modified inclusions. This includes the changes in composition and sizes of inclusions by rare earth addition, promoting the transformation of MnS and Al2O3 in rare earth inclusions with regular shapes, smaller sizes and better performance, or composite rare earth inclusions. The corrosion pits that form in the early stages of corrosion are shallow in depth, fewer in number and light in corrosion degree. The effects of rare earth materials on the rust layer include: rare earth promotes the formation of a more stable corrosion product α-FeOOH, and rare earth promotes the formation of a dense rust layer, which covers the surface of the matrix and hinders the transmission of corrosion ions. The protective effect of the rare earth atomic layer on the substrate and the corrosion inhibition effect of rare earth ions are formed by the segregation of rare earth at the interface. In the end, the existing problems in the research into rare earth steel and future research directions are briefly put forward, including improving the addition process of rare earth steel, theoretical guidance on enhancing the corrosion resistance mechanism of rare earth steel, and extending the research from La, Ce, and Y steel to more rare earth steels.

Radionuclide tracing based in situ corrosion and mass transport monitoring of 316L stainless steel in a molten salt closed loop

In the study, we report an in situ corrosion and mass transport monitoring method developed using a radionuclide tracing technique for the corrosion study of 316L stainless steel (316L SS) in a NaCl–MgCl2 eutectic molten salt natural circulation loop. This method involves cyclotron irradiation of a small tube section with 16 MeV protons, later welds at the hot leg of the molten salt flow loop, generating radionuclides 51Cr, 52Mn, and 56Co at the salt–alloy interface. By measuring the activity variations of these radionuclides at different sections along the loop, both the in situ monitoring of the corrosion attack depth of 316L SS and corrosion product transport and its precipitation in flowing NaCl–MgCl2 molten salt are achieved. While 316L SS is the focus of this study, the technique reported herein can be extended to other structural materials being used in a wide range of industrial applications.

X-ray computed tomography to observe the presence of water in macropores of cementitious materials

Corrosion of steel reinforcement in concrete is a common degradation mechanism occurring in infrastructures worldwide. Even though extensive research has been conducted over the last decades to accurately predict the influence of steel corrosion on concrete durability, a comprehensive understanding of several micro-scale processes simultaneously involved in the corrosion mechanism is still lacking. The application of X-ray Computed Tomography (X-ray CT) can contribute to elucidate these processes, since this technique allows observing the internal status of specimens non-destructively, over time, and with a spatial resolution in the range of µm. Nevertheless, the relatively low sensitivity of light elements (e.g., hydrogen and oxygen) to X-ray CT may hinder the observation of solution within the cementitious matrix. This consideration is discussed in this letter. The results of this study show that the detection of solution in macropores (e.g., air voids) through X-ray CT is not limited by the relatively low attenuation coefficient of the fluid per se, but more by the spatial resolution at which acquisitions are performed and by the dimensions of the porous volume where solution penetrates. The observations reported in this letter may open several opportunities to further study the influence of the moisture conditions of air voids on several degradation mechanisms of reinforced cementitious materials (e.g., steel corrosion, freeze-thaw damage), which have been rarely investigated with X-ray CT according to the literature. The application of these findings could significantly deepen the understanding of several micro- scale processes that affect the durability of reinforced cementitious materials which still need to be elucidated, as further discussed in the present letter.

Investigation of the Corrosion and Passive Behavior of HP-13Cr Stainless Steel in Formate Annulus Protection Fluid

Investigation of the Corrosion and Passive Behavior of HP-13Cr Stainless Steel in Formate Annulus Protection Fluid

Influence of hydrogen sulphide on the corrosion and hydrogenation of 07Cr16Ni6 steel

The effect of hydrogen sulphide concentration on the corrosion behaviour of 07Cr16Ni6 austenitic-martensitic stainless steel in a 5% NaCl  +  0.5% CH3COOH solution was studied to determine the role of H2S in the corrosion product formation and corrosion mechanism. Unstable passivation of steel is detected in a solution containing <100 mg/dm3 H2S. Steel corrodes in an electrochemically active state at >100 mg/dm3 H2S. When the pitting potential is reached, pitting damage occurs at the grain boundaries. The corrosion rate decreases by ∼five times after exposition for 720 h due to the formation of nickel and iron sulphides on the surface. Corrosion is accompanied by the absorption of 4.2–17.5 ppm hydrogen, 62…70% of which is diffusible and can cause hydrogen embrittlement. The scheme of steel corrosion under the influence of different concentrations of hydrogen sulphide is proposed.

High‐potent trifunctional polybenzoxazines coatings for superhydrophobic cotton fabrics and mild steel corrosion protection applications

AbstractNew trifunctional polybenzoxazines were developed and utilized as a high‐potent coating material for superhydrophobic cotton fabrics and mild steel corrosion protection applications. New trifunctional benzoxazines resin have been synthesized using trihydroxytriphenylmethane (TTM) with dimethylaminopropylamine (dmapa), 1‐(3‐aminopropyl)imidazole (ipa) and aminoethoxyethanol (aee) as amine sources with paraformaldehyde through Mannich condensation. The structural confirmation of synthesized benzoxazines was ascertained by spectral studies. The ring opening polymerization of TTM‐Bzs was studied using DSC analysis. All the three TTM‐Bz monomers show curing temperature lower than 210°C. The thermo‐stability and water contact angle (WCA) of polybenzoxazines were studied using thermogravimetric analysis and goniometer, respectively. Among the TTM‐PBz studied, the poly(dmapa) exhibit better thermo‐stability and hydrophobic behavior when compared to rest of the synthesized polybenzoxazines. Poly(TTM‐dmapa)‐coated cotton fabric exhibits the superhydrophobic behavior and mild steel (MS)‐coated specimen possesses the higher charge transfer resistance value of 3.47 × 107 Ω cm2. It was also inferred that all the TTM‐PBz‐coated MS specimens exhibit higher corrosion protection behavior as well as good thermo‐stability and hydrophobic nature. Further, the obtained results suggested that these materials can be suitably exploited for hydrophobic anticorrosion applications with improved performance and enhanced longevity.

Chloride-induced corrosion of steel in concrete-insights from bimodal neutron and X-ray microtomography combined with ex-situ microscopy.

The online version contains supplementary material available at 10.1617/s11527-024-02337-7.

Unraveling the Adsorption and Corrosion Resistance Mechanisms of Pyran-Pyrazole Analogs for Carbon Steel Corrosion in Hydrochloric Acid Based on Practical Approaches and Theoretical Calculations

Unraveling the Adsorption and Corrosion Resistance Mechanisms of Pyran-Pyrazole Analogs for Carbon Steel Corrosion in Hydrochloric Acid Based on Practical Approaches and Theoretical Calculations

The Growth Behavior and Mechanisms of Pitting Corrosion on Super 13Cr Martensitic Stainless Steel Surfaces at Different Diameter-to-Depth Ratios

This study employs finite element analysis and simulated environmental immersion experiments to methodically investigate the growth behavior of pitting corrosion in stainless steel. It particularly examines how the diameter-to-depth ratio of the pit influences its growth dynamics. The findings underscore substantial variations in growth patterns and corrosion rates corresponding to different diameter-to-depth ratios. Key parameters, including electrolyte current density, potential, Fe2+ and Cl− ion concentrations, and pH values, play a crucial role in the corrosion mechanism. Remarkably, a pronounced increase in the corrosion rate at the pit bottom was observed with the increase in the diameter-to-depth ratio to 1:5. The results of this work provide insight into stainless steel pitting mechanisms, enabling the development of more effective prevention strategies.

Enhancement resistance to microbiologically influenced stress corrosion of Cu-bearing steel against Bacillus cereus

Microorganisms are notoriously known to cause local corrosion and stress corrosion cracking (SCC), which seriously endangers the materials service safety. Cu can enhance antibacterial function of the material and reduce the vulnerability to hydrogen embrittlement (HE). However, the dilemma of how much Cu content generates the best resistance to microbiological corrosion and SCC arises. Here, we modified the Cu content in pipeline steel to obtain the best antibacterial effect to nitrate reducing bacteria Bacillus cereus and HE resistance. The findings offer a fresh perspective on how to design and prepare a steel that are both resistant to microbiological corrosion and SCC.

Corrosion of ribbed carbon steels in ecological mortars and its influence on their rotative fatigue behavior

Ribbed carbon steel rebars were embedded in mortars manufactured with three different eco-friendly binders (alkali-activated slag, and slag and fly ash-based hybrid cements) and with a commercial cement (CEM IV). This research evaluates the corrosion of reinforcements, fully assessed by natural diffusion, and its impact on the fatigue performance of the bars. Results obtained after 17-month corrosion testing on reinforced innovative mortars reveal that different pit morphologies and locations appear on the bars depending on the mortar composition, with the extent of the attack being related to the pH and the free-chloride content in each mortar. Rotative fatigue tests of the corroded bars have proven that the reduction of the fatigue life is dependent on the global extent of the corrosive attack, when the shape and distribution of the pits correspond to those generated exclusively by chloride diffusion in mortars. Bars corroded in alkali-activated slag and CEM IV mortars shown the best fatigue performances.

Synthesis, surface activity, and corrosion inhibition capabilities of new non-ionic gemini surfactants

Several environmentally acceptable non-ionic gemini surfactants are synthesized in this work using natural sources, including polyethenoxy di-dodecanoate (GSC12), polyethenoxy di-hexadecanoate (GSC16), and polyethenoxy di-octadecenoate (GSC18). The produced surfactants are confirmed by spectrum studies using FT-IR, 1HNMR, and 13CNMR. It explored and examined how the length of the hydrocarbon chain affected essential properties like foaming and emulsifying abilities. Surface tension examinations are used to assess the surface activity of the examined gemini surfactants. The lower value of critical micelle concentrations (0.381 × 10−4M) is detected for GSC18. Their spontaneous character is shown by the negative values of the free energy of adsorption (ΔGads) and micellization (ΔGmic) which arranged in the order GSC18 > GSC16 > GSC12. Based on theoretical, weight loss, and electrochemical investigations, these novel surfactants were investigated for their possible use in inhibiting carbon steel from corroding in 1 M HCl. Measuring results show that GSC18 inhibits corrosion in carbon steel by 95.4%. The isotherm of adsorption evaluated for the investigated inhibitors and their behavior obeys Langmuir isotherm.

Accelerated corrosion of low carbon steel by oscillatory acidic streams generated with a bio-inspired claw device.

A mechanical device inspired by the pistol shrimp snapper claw was developed. This technology features a claw characterized by a periodic opening/closing motion, at a controlled frequency, capable of producing oscillating flows at transitional Reynolds numbers. An innovative method was also proposed for determining the corrosion rate of carbon steel samples under oscillating acidic streams (aqueous solution of HCl). By employing very-thin carbon steel specimens (25 μm thickness), with one side coated with Zn and not exposed to the stream, it became possible to electrochemically sense the Zn surface once the steel sample was perforated, thus providing the average dissolution rate into the most relevant pit on the steel surface. Furthermore, a laser light positioned beneath the metallic sample, along with a camera programmed to periodically capture images of the steel surface, facilitated the accurate counting of the number of newly formed pits. The system consisting of the thin steel sample and the Zn coating can be seen as a type of corrosion sensor. Furthermore, the proposed laser illumination method allows corroborating the electrochemical detection of pits and also establishing their location. The techniques crafted in this study pave the way for developing alternative corrosion sensors that boast appealing attributes: affordability, compactness, and acceptable accuracy to detect in time and space localized damage.

Corrosion of Old Overhead Lines: Insights into Aluminum-Steel Galvanic Couple Using Electrochemical Techniques

Abstract In order to explain the corrosion inside 20th century power lines, the galvanic corrosion of steel and aluminum from 1949 was examined. In this investigation, 0.1 M Na2SO4 + 1 mM NaCl was used as moderately corrosive medium. Various electrochemical methods were applied to determine the corrosion potential and the different reactions involved in the corrosion process. The thickness of the oxide layer that regulates the corrosion of aluminum was obtained from impedance measurement and it was shown that the diffusion of oxygen through a porous oxide layer is the governing stage for the reaction occurring at the steel electrode. Finally, the corrosion of steel regulates the corrosion of both metals when they are in electrical contact.

Novel high-performance and cost-effective green inhibitor based on fundamental theoretical evaluations combined with electrochemical/surface examinations of Arachis hypogaea shell extract for pipeline steel corrosion in 1 M H2SO4 solution

Traditional corrosion inhibitors have been frequently used for metal protection against strong acids. However, most of them are hazardous compounds with high costs. Therefore, due to the strict environmentally friendly regulations, green and low-cost compounds from renewable sources have gained high consideration in recent applications. In the present study, the Arachis hypogaea shell extract, commonly called groundnut, a cost-effective was selected to inhibit API X 65 pipeline steel corrosion in 1 mol·L−1 H2SO4 solution. The Arachis hypogaea shell composition was examined by FTIR analysis. The Arachis hypogaea shell on pipeline steel in H2SO4 solutions was studied via gravimetric, potentiodynamic polarization, and surface analysis (SEM and EDX). Electron donor atoms present in the Arachis hypogaea shell extract molecules is responsible for its adsorption on the surface of the metal. Experimental study shows that with increasing Arachis hypogaea shell concentrations, the inhibition tendency increased and reached 98.84% at 4 g L−1 after 24 h. Arachis hypogaea shell extract behaved as mixed-type inhibitor, and the surface coverage fits the Langmuir isotherm, signifying that the steel surface was covered by a monolayer of inhibitor molecules without intermolecular interactions. SEM analysis shows that Arachis hypogaea molecule adsorption on the metal surface reduced considerably its dissolution rate resulting in a smooth and clean surface with few damaged areas. The use of water for extraction of Arachis hypogaea shell exhibiting inhibition efficiency, non-toxic, and cost-effective than other green inhibitors, proposes the Arachis hypogaea shell as an excellent green inhibitor for API X 65 steel corrosion in 1 mol·L−1 H2SO4 solution.

Ni–Zn bimetal-organic framework nanoprobes reinforced polymeric coating to achieve dual-responsive warning of coating damage and interfacial corrosion

Coating microdefects and localized corrosion in coating/metal system are inevitable, accelerating the degradation of metal infrastructure. Early evaluating coating microdefects and detecting corrosion sites are urgent yet remain challenge to achieve. Herein, we propose a robust, universal and efficient fluorescence-based strategy for hierarchical warning of coating damage and metal corrosion by introducing the concepts of damage-induced fluorescence enhancement effect (DIE) and ionic-recognition induced quenching effect (RIQ). The coatings with dual-responsiveness for coating defect and steel corrosion are constructed by incorporating synthesized nanoprobes composed of metal organic frameworks (Ni–Zn-MOFs) loaded with Rhodamine B (RhB@MOFs). The initial damage to the coating causes an immediate intensification of fluorescence, while the specific ionic-recognition characteristic of RhB with Fe3+ results in an evident fluorescence quenching, enabling the detection of coating damage and corrosion. Importantly, this nanoprobes are insensitive to the coating matrix and exhibit stable corrosion warning capability across various coating systems. Meanwhile, electrochemical investigations indicate that the impedance values of RM/EP maintain above 108 ​Ω ​cm2 even after 60 days of immersion. Therefore, the incorporation of fluorescent nanoprobes greatly inhibits the intrusion of electrolytes into polymer and improves the corrosion protection performance of the coating. This powerful strategy towards dual-level damage warning provides insights for the development of long-term smart protective materials.

Atmospheric corrosion of carbon steel: Results of one-year exposure in an andean tropical atmosphere in Colombia

In this study was examined the response of carbon steel to atmospheric corrosion after one-year exposure in Valle de Aburrá, a subregion located in northwestern Colombia. The study involved the assessment of material mass loss and corrosion rate, the characterization of atmospheric aggressiveness, and the analysis of the morphology and composition of corrosion products in five different sites. Climatological and meteorological factors were assessed by testing for chloride content, sulfur dioxide levels, and time of wetness (TOW). The analysis of corrosion products was conducted using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Raman spectroscopy. Based on corrosion rates, two sites exhibited a more aggressive environment, with a corrosivity category of C3, while the remaining sites were categorized as C2. The study confirmed the presence of lepidocrocite and goethite phases on the surface of carbon steel at all test sites. Data analysis revealed that both the TOW and the industrial activity significantly influence the corrosion of this metal.