Erosion Corrosion Research Articles

Carbon steel pipeline CO2 erosion-corrosion damage prediction model and numerical simulation research

CO2 erosion-corrosion (E-C) represents a significant and pervasive threat to the integrity of carbon steel pipeline in the oil and gas industry, which has attracted more and more attention. On this basis, a CO2 E-C damage prediction model considering the synergistic effect is established combining with multiphase flow model, corrosion model and CO2 corrosion model, in which the Eulerian-Lagrangian discrete particle method is employed in the multiphase flow model and the CO2 corrosion model is modified and verified by the erosion-corrosion test method. By using the CFD-DPM technology, the three-dimensional numerical simulation of the elbow is carried out to demonstrate the characteristics of the prediction model, and the dominant factors and extent of CO2 E-C damage can be determined based on the numerical simulation results. Both erosion and corrosion are non-negligible parts that lead to CO2 E-C damage, with corrosion factors being the more important factor to be considered. The prediction results can not only provide suggestions for improving the design of carbon steel pipelines in the oil and gas industry, but also provide protective measures for the operation of existing pipelines to extend their service life, which is helpful for the development and implementation of plans in the oil and gas industry.

High-Temperature Erosion–Corrosion Performance of Plasma and High-Velocity Oxy-Fuel Sprayed TiC and TiN Enriched Ni-20Cr Coatings in an Actual Boiler Environment

High-Temperature Erosion–Corrosion Performance of Plasma and High-Velocity Oxy-Fuel Sprayed TiC and TiN Enriched Ni-20Cr Coatings in an Actual Boiler Environment

Eect of acid corrosion on physico-mechanical parameters and energy dissipation of granite

In deep underground engineering, it is inevitable that portions of the rock mass will be subjected to the erosion and chemical corrosion of infiltrating water. A comprehensive study of the physical, mechanical, and energetic properties of rocks after hydrochemical corrosion is crucial for ensuring the stability of the rock mass. The novelty of this research lies in the detailed investigation of the macroscopic and microscopic morphologies of rocks exposed to various corrosive solutions, as well as the changes in various physical and mechanical parameters. Utilizing the weighting method, a scientific comprehensive evaluation system for deep rocks after hydrochemical corrosion has been established. The results indicate a pronounced sensitivity of the macroscopic and microscopic morphologies to pH values. The longitudinal wave velocity of the corroded rock decreases obviously, with the maximum decrease being 13.46%. As the pH value decreases (from 7 to 3), the compressive strength, elastic modulus, cohesion, and internal friction angle of the rocks all decrease significantly. The acidity of the solution significantly aects the changes in the three types of strain energy of the rocks, with higher acidity leading to weaker energy storage capability. Among the factors influencing the characteristics of strain energy variation in rocks, confining pressure has a higher priority than pH value. This study precisely evaluates the impact of hydrochemical corrosion on rock damage using a percentage-based scoring system, and found that granite’s score dropped from 81 to 16. The research findings provide valuable insights for the evaluation of rock mass stability under hydrochemical corrosion conditions.

Identifying failure factors due to corrosion erosion on pressured steam pipe elbow in geothermal power plant

This paper presents the findings of a corrosion erosion failure analysis of elbow pipe materials used to flow high-pressure water from underground. The failed elbow pipe material was above the wellhead forming a straight line in the longitudinal direction with a pipe length of 6200 feet below the ground surface. The working fluid in the elbow pipe was 25 % steam and 75 % water, flowing in the elbow pipe with a media flow rate of 180 tons per hour, a pressure of 22 bar, and a temperature of 220 °C. Elbow tubes were made of low carbon steel with Standard ASTM A234 having an outer diameter of 304.8 mm and a wall thickness of 9.271 mm. Macroscopic testing, chemical composition analysis, metallographic testing, hardness testing, X-ray diffraction testing, SEM, and EDS are a few of the test types conducted. The study's findings showed that the elbow tubes experienced a thinning process on the inner wall of the outer curvature side with a rough and wavy surface texture or appearance. This type of failure is known as erosion-corrosion. The level of erosion-corrosion failure that occurs is greatly influenced by the pH of the fluid being flowed reaching 2.67–2.91, this is due to the very high Cl- of 1290 ppm, so the higher the rate of erosion-corrosion that occurs. These materials are the most popular and widely used in the oil and gas sector. However, this pipe has weaknesses because it is susceptible to erosion-corrosion Therefore, it is very important to choose the right material, namely, a material that is resistant to erosion-corrosion

Understanding the role of alloying elements Cr, Ni in erosion–corrosion process of nuclear grade austenitic stainless steel 304 L by total reflection X-ray fluorescence

Stainless steel (SS) has gained an indispensable position as one of the most widely used industrial material. In nuclear industry, it is one of the technologically most important structural materials used in pressure tube, containment vessel and reprocessing-related applications. In fact, SS 304 L is the workhorse material of the reprocessing plant which faces the hostile conditions of acid, temperature as well as high radiation dose. These conditions can affect the erosion-corrosion behavior of the material and can lead to poor mechanical properties. This also affects the life of the reactor components. In the present study, a systematic work has been carried out to develop an in-depth understanding of the Corrosion Rates (CRs) with respect to the loss of major and minor elements from SS into the corrosive nitric acid medium using Total reflection X-Ray Fluorescence (TXRF). The effect of acid molarity as well as temperature, on the erosion-corrosion behavior of SS304L was studied. The TXRF studies have revealed that the CR was maximum in 2 M HNO3 and minimum in 8 M, showing that the nitric acid molarity has an important role to play in the corrosion and as the molarity increases, the passivation of SS 304 L also increases. This observation was further corroborated with the concentrations of Fe, Cr and Ni, which had leached into the nitric acid medium. The role of alloying elements, Cr and Ni, in the passivation of SS was also studied. The effect of temperature showed that at 45 °C, the rate of corrosion was minimum, as compared to at 25 °C and 90 °C which reveals that the formation of chromium oxide passive layer was thermodynamically most favorable at this temperature.

Influences of Sr(OH)2 on the Structure and Corrosion Resistance of Micro‐Arc Oxidation Coatings Formed on TC4 Titanium Alloy

ABSTRACTIn order to improve the comprehensive properties of TC4 titanium alloy, micro‐arc oxidation (MAO) coating is prepared on the surface of a TC4 substrate in a basic electrolyte with varying concentrations of Sr(OH)2. The surface morphology, phase composition, element distribution, and corrosion resistance of MAO coatings are analyzed by scanning electron microscopy, X‐ray diffraction, an energy‐dispersive spectrometer, the electrochemical test, and the erosion–corrosion test. The results show that the voltage of the MAO process increases and then decreases; the surface morphology and density of the coatings are greatly improved after doping Sr(OH)2. When the concentration of Sr(OH)2 is 0.6 g L−1, the thickness, hardness, and adhesion strength of the coating reach the maximum values of 37.04 μm, 836.2 HV, and 21.8 N, respectively. At this time, the wear resistance and corrosion resistance are the best, and the friction coefficient and the corrosion rate are the lowest: 0.3352 and 1.04 × 10−10 mm a−1, respectively.

Enhanced cavitation erosion and electrochemical corrosion properties of additively manufactured Hastelloy C276 coating by ultrasonic shot peening

Enhanced cavitation erosion and electrochemical corrosion properties of additively manufactured Hastelloy C276 coating by ultrasonic shot peening

Investigation of the effect of elbow pipes of Ti6Al4V, 304 stainless steel, AZ91 materials on erosion corrosion by finite element analysis

Corrosion is the degradation of metals caused by chemical or electrochemical reactions with their environment. As a result of these reactions, undesirable conditions occur in the physical, chemical, mechanical and electrical properties of metals. These conditions cause parts made of metallic materials to become unusable. Erosion corrosion is one of the most common types of corrosion in fluid transfer. There are several methods for preventing erosion corrosion. First of all, some precautions should be taken to prevent wear. Intervention is very important in terms of cost, especially at the design stage. Measures such as wide angle bends, wall thickness of wear-resistant material and corrosion allowance can be taken, especially in applications where the flow direction needs to be changed. The aim of this study was to determine the effect of liquid fluid on erosion corrosion in Ti6Al4V, 304 stainless steel and MgAz91 elbow pipes by using the computer aided and finite element based AnsysWorkbench Explicit Dynamics module. For the design of the elbow pipe, SolidWorks was used for 3D studies. In the analysis of the pipe, the suitability of the pipe for the 3D model was examined. The effect of fluid rotation on the pipe walls and the effect of the pipe material on the flow along the pipe were determined. The standard k-e model based on the velocity-pressure relationship in continuous and steady flow was used for the flow calculations. The flow simulation showed that for all models the flow accumulation after rotation was more concentrated on the opposite walls of the pipe, as expected. The results obtained showed that the deformation in MgAZ91 material had the highest value at 9.14 × 10−8 mm. This situation has been interpreted to mean that it may vary depending on the flow rate automation. Designs on the old designs in the erosion structure of the liquid that occurs in the pipes with a new product design in the analysis design.

Experimental research of corroded concrete beams with natural cooling after fire considering the bond deterioration

The residual bearing capacity after fire is of great significance for safety assessment and repair of building structures. To accurately evaluate the residual strength of corroded beam after natural cooling, this study investigated the residual bearing capacity of corroded beam considering the bond deterioration after fire exposure. First, the bond behavior and flexural-deformation capacity was conducted by pullout test and bending test after corrosion erosion and fire temperatures damage. The bond deterioration test shows that when the temperature rises above 200℃ and the corrosion level exceeds 4.3%, the bond strength decreases by 16.5%. At the temperature reaches 600℃ or the corrosion degree reaches 13.8%, the bond behavior damage exceeds 50%. The bending test indicates that corrosion and high temperature damage both decrease the bending bearing capacity of the beam, but the influence of high temperature damage on the residual bearing capacity is greater than that of corrosion. The bond property deterioration decreases the strain value of the tensile rebar during the bending process, and decreases the bending capacity of the beam. Finally, a bond-slip constitutive model suitable for corroded beams after fire is proposed, which is applied to the calculation of the ultimate moment of the beam. The modified value of beam bearing capacity considering bond deterioration has better collimation and higher safety margin. The bond-slip constitutive model and the modified calculation method of bending moment of beam are helpful to provide more accurate performance assessment of beam after the coupling effect of corrosion and fire damage.

Investigation on corrosion behavior of the atmospheric pressure air cooler tubes caused by multiphase flow

Air coolers are important heat exchangers and widely used in the petroleum and petrochemical industries. The leakage of air cooler tubes due to corrosion frequently happened and seriously affected normal production process leading to unplanned shutdowns, so the corrosion behavior of the air cooler tubes needed to be clarified urgently. In this work, the corrosion behavior of the atmospheric pressure air cooler tubes was investigated by computational fluid dynamics (CFD) simulation and experimental study. It was depicted that the gas–liquid erosion corrosion was the main reason for the leakage of air cooler tubes and the collision angle between the fluid flow and the wall at the inlet of the tubes was the key factor that affects the corrosion behavior of the multiphase flow inside the air cooler tubes. The corrosion was most severe when the collision angle is 30 degree. With the purpose to migrate corrosion, the improvement measure was proposed from the perspective of collision angle elimination. The porous plates were installed and the lifetime of the air cooler tubes was extended to 4 times that of the original conditions, which indicated the installation of porous plates is an effective measure to reduce corrosion.

Effect of acid mine drainage on the mechanical properties of AISI 1020 carbon steel and AW6060 aluminium

Acid mine drainage severely affects metallic materials due to the high acidity and oxidising capacity of these lixiviates. A study was carried out to evaluate the time evolution of the mechanical properties of AISI 1020 carbon steel and AW6060 aluminium in contact with acid mine drainage. Weight loss, fatigue and tensile strength were evaluated in two different scenarios, one involving erosion corrosion (dynamic scenario) and the other involving chemical corrosion only (static scenario). Over 80 days of exposure in a static scenario, weight loss is almost 2% for aluminium and 0.5% for steel, fatigue strength is reduced by 28% for steel and ultimate tensile strength is reduced by almost 5% for aluminium and by 2.5% for steel. In a dynamic scenario, the weight loss after 4 days of exposure is 30–35% for both materials, the fatigue strength is reduced by almost 50% for steel, the ultimate tensile strength is reduced by 33% for aluminium and by almost 5% for steel. Acid drainage causes an increase in brittleness and a decrease in stiffness of these materials, much more rapidly in a dynamic environment favoured by the effects of erosion corrosion.

Research Progress on Influencing Factors of Erosion Corrosion in Oil Pipelines

Original sentence: "Erosion corrosion is a significant factor contributing to the thinning and failure of oil pipelines. This paper addresses the issue of erosion corrosion of oil pipelines in oil fields under the action of multiphase flow, the main factors affecting the erosion corrosion are introduced, including the hydrodynamic factors, solid particle properties, fluid medium properties and temperature, It summarizes and analyzes the mechanisms through which these different factors affect the erosion corrosion of oil pipelines. The paper points out that increased fluid velocity in oil pipelines, sudden changes in flow patterns, and turbulent kinetic energy can accelerate erosion corrosion to some extent, With the increase of flow rate, erosion corrosion mechanism will change from electrochemical corrosion dominant to erosion accelerated corrosion, There is a maximum value for erosion corrosion based on the solid particle impact angle. The harder and sharper the solid particles are, the stronger their impact on the pipeline, especially the impact of low Angle impact is more significant; however, the diameter and quantity of particles can affect the development of erosion corrosion due to 'particle size effect' and 'shielding effect.' Additionally, lower pH values and higher temperatures of the fluid medium will increase pipeline erosion corrosion. Finally, future research directions for studying erosion corrosion in oilfield pipelines under multiphase flow conditions are discussed in light of existing research."

Influence of sand particle size on the erosion-corrosion resistance of Ni2FeCrMo0.2 HEA in seawater: Particle-surface-electrochemistry interaction

The erosion-corrosion mechanism in rotary flowing seawater is hugely complicated due to the multiscale coupling processes of particle-surface impact, ion mass transfer, and interface electrochemistry. Therefore, developing erosion-corrosion resistant material and exploring the synergistic mechanism between sand erosion and electrochemical corrosion is vital. This study conducted the erosion-corrosion test on Ni2FeCrMo0.2 high-entropy alloy under the particle-seawater flow. Based on a coupled analysis of multi-component weight loss, electrochemical behavior, and microscopic damage morphology, the multiscale coupling processes of sand transportation, particle-surface impact, ion mass transfer, and interface electrochemistry were revealed. The present study found that with the increase of sand size, the energy carried by the particles promoted impact erosion. Additionally, particle movement enhanced ion mass transfer through turbulent effects, and the impact behavior disrupted the passivation film to promote electrochemical processes by reducing the thickness of the passivation film, leading to an increase in the erosion-corrosion rate. However, when the particle size continued to increase to a certain extent, the impact frequency decreased, reducing the erosion-corrosion rate. As the sand size grew, the dominant damage mechanism transitioned from pure corrosion (100 μm) to synergistic effects (200 μm, 400 μm) and then to pure erosion (800 μm). This study provides an in-depth understanding of the erosion-corrosion mechanism in seawater from the perspective of particle-ion-fluid-surface interaction by multi-element characterization.

Tunable Dual Self-Healing Composite Coatings with Self-Assembled Structures Regulated by Janus Nanoparticles.

The durability of concrete structures can be enhanced in a convenient and permanent manner through the surface protection of cementitious materials with composite polymer coatings. However, polymer coatings are susceptible to various mechanical and physical deterioration in complex and variable environments. In this paper, the theory of polymer microstructure regulation was employed to improve the sustainability of the protective performance of composite coatings. The self-assembled core-shell structure regulated by amphiphilic Janus nanoparticles is employed to modify the tunable polystyrene acrylate-polysiloxane self-healing coatings. The results demonstrate that the adhesion strength of the prepared self-assembled coating reached 3.7 MPa, which is sufficient to resist the damage to the microstructure of cementitious materials caused by physical erosion, seepage, and ionic corrosion. The self-healing coating, regulated by Janus particles, exhibited a residual creep of only 57.03% and a maximum loss angle tangent of 0.381. Furthermore, the material exhibited a superior shape memory function due to the presence of strong hydrogen bonding. The regulated self-healing coating repaired the polymer structural damage under mechanical and thermal deformation by bridging and filling effects. The coating demonstrated a tensile strength recovery of up to 71.23% in a wetted state, accompanied by a rapid restoration of its electrochemical properties and corrosion resistance. Furthermore, the self-healing emulsion penetrates the substrate defects and forms numerous polymer crystalline particles that effectively fill the microcracks.

A Dynamic Testing Approach for Particulate Erosion–Corrosion for Gas Turbine Coatings

Abstract Particle interactions in engines can be complex phenomena leading to degradation of thermal (TBCs) and environmental barrier coatings (EBCs) meant to protect engine components. Ingestion of particles into the engine can lead to recession of coatings due to particle erosion. Similarly, these particles can become molten, adhere to coatings, and result in thermochemical corrosion of coating materials. Erosion testing is often carried out where particles are injected into a gas stream, accelerated within a nozzle, and impinge on samples. Conversely, most molten particle corrosion testing is often done in static furnaces, which does not capture the dynamic nature of deposition. Nevertheless, these damage mechanisms are often tested separately, and no standard exists to test both erosive/corrosive particle interactions with coating materials under relevant turbine operating conditions. Understanding the synergies of particle interactions is crucial in determining operating lifetimes of potential coating materials. Such considerations emphasize the need for realistic approaches in standardizing particle interaction testing in combustion environments. This study outlines efforts at NASA Glenn's Erosion Burner Rig Facility in improving dynamic erosion/corrosion testing methods by assessing the durability of state-of-the-art (SOA) TBC 7 wt % yttria-stabilized zirconia (7YSZ) as a function of particle deposition rate, burner temperature, and particle size. Calibration data to determine particle deposition rate will be presented, and mass and optical profilometry measurements were utilized to estimate mass/volume loss versus deposition per increment of particulate used. Electron microscopy analyses were then carried out to assess coating damage after testing.

Enhancement of Plain Carbon Steels Corrosion by Heat Treatment of the Direct Electrodeposited Ni-P-SiC Deposit

The current study examined the effects of heat treatment on the microhardness and wear resistance of electrodeposited Ni-P-SiC coatings, as well as the effects of SiC particle concentrations on the coating's metallic continuous phase. Direct electrodeposition onto a low alloy steel electrode (0.40 C) was used to obtain the deposits. A modified Watt bath and pure nickel anode were used, and the material was heat treated for one hour at 400 °C. Using XRD and SEM methods, the Ni-P-SiC deposit was characterized. Additionally, the deposit's microhardness was assessed using the LECO, DM-400, both before and after heat treatment, with a 50g load. The results obtained indicate that the coating's deposition on the surface of low alloy steel and its impacts on the deposit coating crystal plane may be influenced by the applied current density. The SiC dispersion slightly improved as the bath's SiC content rose. The reduction in phosphor content of the deposited Ni-P-SiC coating as a result of the SiC particles being added to the Ni-P electrodeposition bath. The XRD data showed that crystalline Ni and Ni3P are formed as a result of the heat treatment procedure. As the SiC content in the electrodeposition bath and heat treatment procedure rises, so does the microhardness of the Ni-P-SiC deposit. Low alloy steel's resistance to erosion corrosion can be strengthened by the Ni-P-SiC.

Erosion and intergranular corrosion induced failure of S31254 stainless steel – Case study on Venturi scrubber in a natural gas purification plant

The flue gases such as SO2, SO3, and CO2 generated during the purification process of sulfur-containing natural gas need to be treated to a certain concentration before they can be discharged into the atmosphere. The flue gas unit of a purification plant in Sichuan adopts the new Cansolv flue gas treatment process. After running for a period of time, the Venturi scrubber experienced severe corrosion failure, resulting in equipment shutdown and significant economic losses. This paper utilizes an actual failed device as a case study to analyze the corrosion environment of the Venturi scrubber. It conducts a comprehensive failure analysis, encompassing material mechanical properties, metallographic analysis, and failure microstructure analysis, aiming to elucidate the reasons behind the Venturi scrubber failure. Systematic analysis shows that the manufacturing materials used in this scrubber meet all design requirements. However, flue gas at temperatures reaching 280 °C enters the scrubber tower at a flow rate exceeding 10 m/s. The dissolution of acidic gases leads to a significant drop in the pH of the cooling water to 1, manifesting evident signs of erosion corrosion and intergranular corrosion on the material surface. These observations suggest that erosion and intergranular corrosion in high-temperature acidic environments are the predominant factors contributing to the corrosion failure of the Venturi scrubber.

Effect of Single Particle High-Speed Impingement on the Electrochemical Step Characteristics of a Stainless-Steel Surface.

In the process of particle erosion and electrochemical corrosion interaction, the electrolyte flow state change, product film destruction, and matrix structure change caused by particle impact affect the electrochemical corrosion process. Such transient, complex physical and electrochemical changes are difficult to capture because of the short duration of action and the small collision area. The peak, step time, and recovery time in this transient step cycle can indirectly reflect the smoothness and reaction rate of the electrochemical reaction system, and thus characterize the resistance to scouring corrosion coupling damage of metals in liquid-solid two-phase flow. In this study, in order to obtain the electrochemical response at the moment of particle impact, electrochemical monitoring experiments using a specially designed miniature three-electrode system were used to test step-critical values, including step potential, current, and resistance, among others. Meanwhile, an electrochemical step model under particle impact considering boundary layer perturbation was developed. The experimental results reflect the effect law of particle impact velocity and particle size on the peak step and recovery period. Meanwhile, the effect of particle impingement on the electrochemical step of stainless steel in different electrolyte solutions was obtained by comparing the step curves in distilled water and Cl-containing water. The connection between the parameters in the electrochemical step model and in the particle impact, as well as the effect of the variation of these parameters on the surface repassivation process are discussed in this paper. By fitting and modeling the test curves, a new mathematical model of electrochemical step-decay under single-particle impact was obtained, which can be used to characterize the change pattern of electrochemical parameters on the metal surface before and after the impingement.

Erosion–Corrosion Behavior of As-cast and Destabilized High Chromium Cast Irons with Mo and W Addition

Erosion–Corrosion Behavior of As-cast and Destabilized High Chromium Cast Irons with Mo and W Addition

Tribo-Corrosion Control with Molecules of Bio-Origin: Experimental Studies and Theoretical Insights

Tribo corrosion control of 6061 aluminum alloy was done by using naturally available Boswellia serrata (BWS) extract as green inhibitor. Studies were done in artificial sea water slurry containing 0.03% sand particles via a submerged jet impingement technique. Electrochemical studies were the majour techniques adopted for corrosion rate measurement in the absence and in the presence of inhibitor. Investigation was done at different flow rates and at different temperatures. Detailed surface study was done for sand particles before and after impingement using scanning electron microscope. Surface morphology of aluminum sample was done before and after the addition of inhibitor. For a given flowrate inhibition efficiency decreased with increase in temperature. This suggested the possibility of physical adsorption. Results were fitted into suitable adsorption isotherm. Mechanism of adsorption was supported and substantiated by quantum chemical calculations using Density Functional Theory (DFT). The best corrosion–erosion resistance was obtained at a concentration of 1000 ppm Boswellia serrata at 303 K under 4 L min−1. DFT studies supported the adsorption mechanism of the inhibitor on the surface of metal under tribological conditions. The outcome of this work will help in research that is focused on development on green inhibitors for corrosion inhibition under dynamic multi flow conditions.