Corrosion Rate Of Materials Research Articles

Machine Learning Approach to Investigate High Temperature Corrosion of Critical Infrastructure Materials

AbstractDegradation of coatings and structural materials due to high temperature corrosion in the presence of molten salt environment is a major concern for critical infrastructure applications to meet its commercial viability. The choice of high value coatings and structural (construction parts) materials comes with challenges, and therefore data centric approach may accelerate change in discovery and data practices. This research aims to use machine learning (ML) approach to estimate corrosion rates of materials when operated at high temperatures conditions (e.g., nuclear, geothermal, oxidation (dry/wet), solar applications) but geared towards nuclear thermochemical cycles. Published data related to materials (structural and coatings materials), their composition and manufacturing, including corrosion environment were gathered and analysed. Analysis demonstrated that random forest regression model is highly precise compared to other models. Assessment indicates that very limited sets of materials are likely to survive high temperature corrosive environment for extended period of exposure. While a higher quality and larger dataset are required to accurately predict the corrosion rate, the findings demonstrated the value of ML’s regression and data mining capabilities for corrosion data analysis. With the research gap in material selection strategies, proposed research will be critical to advancing data analytics approach exploiting their properties for high temperature corrosion applications. Graphical Abstract

Analysis the Effect of Different Surface Preparation Methods on Corrosion Resistance and Adhesion Strength of ASTM A36 Steel Substrate with Surface Tolerant Epoxy Paint as Coating Material

In the industrial world, to extend the service life of materials, protection methods are carried out to slow down the material's corrosion rate. The protection method that is often used is the coating method. The coating method is a protection method by coating the substrate material using a coating material to prevent contact between the substrate material and the environment. In this research, the substrate material used is ASTM A36 steel and the coating material used is Surface Tolerant Epoxy paint. The independent variable used in this study lies in the surface preparation method which consists of: solvent cleaning, hand tool cleaning, power tool cleaning, power tool to bare metal cleaning, and abrasive blast cleaning. Different preparation methods result in different roughness and cleanliness of the surface. This can affect changes in the mechanical properties of the coating material, such as corrosion resistance and adhesion strength. Based on the corrosion resistance test, it is found that the abrasive blast cleaning and power tool to bare metal cleaning methods produce the highest corrosion resistance properties because both have a rating number of 8 in the salt spray test results. Based on the adhesion strength test, it is found that the abrasive blast cleaning method also produces the highest adhesion strength. This conclusion refers to the results of the tape x-cut test where the sample produces a rating number 5A where the sample does not experience peeling after testing. In addition, the abrasive blast cleaning method produced the highest adhesion strength in the pull-off test, which was 7.16 Mpa. Thus, the abrasive blast cleaning method is the most effective surface preparation method for ASTM A36 steel before being coated with the coating material. In addition, it can also be concluded that the higher the surface roughness of the sample, the better the corrosion resistance and adhesion strength.

Effect of Phenolic Resin Coating Thickness on Mechanical Properties and Corrosion Resistance of Metal Materials

In the realm of petrochemical and other industries, metal materials face threats such as impact and high-temperature electrochemical corrosion. Consequently, there has been significant attention towards organic coatings that effectively attenuate impact forces while simultaneously providing a barrier against corrosive agents. The thermosetting phenolic resin 2130, known for the facile curing process, exceptional thermal stability, water resistance, corrosion resistance, and superior mechanical properties post-curing, finds extensive applications in the field of coatings. To address the challenge of depositing a complete and uniform resin coating on complex workpieces, coatings with varying thicknesses on the surface of 304 stainless steel were deposited via rotary evaporation combined with long-term low-temperature drying. The relationship between coating thickness and mechanical properties, as well as corrosion resistance, was investigated and analyzed through a comprehensive approach involving mechanical testing, electrochemical analysis, and long-term service weight loss assessment. The results demonstrated that the coatings deposited on the metal surface exhibited excellent integrity and compactness. Moreover, an increase in coating thickness led to a significant reduction in material corrosion rate. The coatings exhibited excellent substrate adhesion and flexibility, thereby providing effective protection against impact on the metal substrate. The relationship between the thickness of the coating and the surface roughness was evident, while the flexibility of the coating first increased and then decreased with the increase of coating thickness. When the coating thickness was 7 μm, the maximum surface roughness of the coating measured 0.44 μm. Under these conditions, the impact toughness of the coating reached the peak, exhibiting a ductile fracture mode and showcasing superior comprehensive mechanical properties. The findings of this study will offer theoretical support for the investigation and formulation of resin coatings in subsequent industrial production.

Microstructural evolution, mechanical properties and corrosion mechanisms of additively manufactured biodegradable Zn-Cu alloys

Additively manufactured (AM) biodegradable zinc (Zn) alloys constitute an important branch of orthopedic implants because of their moderate degradation properties and bone-mimicking mechanical properties. In this paper, the microstructural evolution and corrosion mechanisms of zinc-copper (Zn-Cu) alloys prepared by the laser-powder-bed-fusion (L-PBF) additive manufacturing method were investigated. Alloying with Cu significantly increases the ultimate tensile strength (UTS) of unalloyed Zn, but the UTS and ductility of unalloyed Zn and Zn-2Cu decrease with increasing laser energy density. Unalloyed Zn has a dendritic microstructure, while Zn-2Cu alloy has a peritectic microstructure. The formation of round peritectic grains is due to the low-temperature gradient of unalloyed Zn during the AM. The Zn-2Cu samples exhibited higher corrosion rates, addressing the problem of slow degradation of unalloyed Zn. The grain size distribution influences the corrosion behavior of the material. It enhances the corrosion rates of materials with fine grains in a non-passivating environment. However, the 100% extracts of Zn-2Cu samples exhibited greater values of cellular activity compared to unalloyed Zn samples, thus confirming their better cytocompatibility. This work demonstrates the great potential to design and modulate biodegradable Zn alloys to fulfill clinical needs by using AM technology.

Measurement system for in-situ estimation of instantaneous corrosion rate in supercritical water

Current research of cladding and in-core materials for the supercritical water reactor concept is focused on Fe-Cr-Ni alloys (e.g. 800 H, 310 S). Along the standard measurements of general corrosion rate of materials by exposure testing in autoclaves, where poor reproducibility is an issue, especially when comparing results from different experimental facilities, a good alternative may be the use of in-situ electrochemical measurements. The use of electrochemical methods is, however, more challenging due to complicated instrumentation as well as due to the supercritical water conditions. This paper is focused on the design of an experimental facility for in-situ electrochemical testing at supercritical water conditions, i.e. main circulating loop with autoclave, including the design of the electrode system, electrode leads and their surface insulation coating. Stability of electrochemical measurements has been tested using 2- and 3-electrode set-ups. Finally, surface insulation coating of the electrode leads with the best chemical and mechanical stability during experiment has been chosen for the presented application.

Corrosion resistance of fluorescent carbon fiber reinforced FEVE and fluorescence detection of coating surface

Fluorocarbon resin coating plays a significant role in marine severe corrosion protection. However, seawater has a great influence on the corrosion rate of materials, so it is necessary to strengthen the monitor of marine materials during service. In this study, using solvothermal method, the rare earth (RE) europium nitrate, 1.10-phenoline and concentrated nitric acid oxidized carbon fiber (CF) were chemically doped in the reactor to prepare a kind of carbon fiber with fluorescent characteristics. Then, the RE modified CF was mechanically mixed with fluorocarbon resin to prepare a fluorescent indicator anti-corrosive coating with intrinsic red light emission guided by Eu3+ ultra-sensitive electric dipole transition (5D0→7F2). The correlation between corrosion time and fluorescence spectroscopy could be established to detect the corrosion resistance of the coating, it provides a reference for the anti-corrosion intelligent indication of the coating.

Corrosion of Brass Fishing Vessel Propeller in Artificial Seawater

The propeller was an important component in the fishing vessels marine propulsion system. Brass was widely used as a fishing vessel propeller. Brass was chosen because it has good mechanical properties and good corrosion resistance. The content of seawater in Indonesia has levels of 3% – 3.5% NaCl. In addition to the level of Ion Cl-, environmental factors can affect corrosion rate of material or metal. The environmental factors that affect the corrosion rate are the level of salinity, pH, DO, temperature and TDS. The objective of the present work was to explain the corrosion rate of brass in artificial seawater in Indonesia with exposure time. The material used for research is fishing vessel propeller commercial in Indonesia market. Measurement of the corrosion rate of brass used the principle of weight loss according to ASTM G31-72 (2004). During the corrosion test, the artificial seawater solution was tested for its pH and salinity quality over time of immersion. The result of immersion brass in the artificial seawater shows that the corrosion rate decreases in 1-to-10-days exposure time due to the increase in salinity levels above 30‰. While the results of exposure time immersion above 15 days tends to increase the corrosion rate due to a decrease in pH level. pH level of seawater depends on the environmental conditions and tends not to change significantly.
 Keyword: Artificial Seawater, Brass, Corrosion Rat, pH, Salinity.

Effect of anodizing on aluminum alloy 2024 with boric sulfate acid in medium 3.5 % NaCl

The utilization of metal materials finds widespread applications in various industries, including the aircraft industry, where aluminum alloys are commonly employed. However, metal materials are prone to corrosion under specific conditions, necessitating the implementation of corrosion prevention methods to decelerate the material's corrosion rate. Corrosion is a process in which the quality of metal deteriorates due to environmental influences. An effective approach to inhibit corrosion is through anodizing, which involves applying a protective coating to the metal surface, preventing direct contact with the surrounding environment. In this research, the focus was on studying the corrosion rate of aluminum alloy 2024 using Boric Sulfate Acid Anodizing (BSAA) at 10 volts and immersion times of 10, 15, and 20 minutes, followed by sealing with acetic acid in a corrosive environment containing 3.5 % NaCl. The main goals were to evaluate the effectiveness of anodizing with and without sealing in lowering the rate of aluminum corrosion, to compare the effectiveness of anodizing with and without sealing, and to create adsorption models using Langmuir adsorption. Through the examination of the potentiodynamic approach, it was shown that anodizing had an inhibitory impact that was strengthened by sealing. The maximum efficiency of 76 % was attained after 20 minutes of anodizing and sealing at 10 volts. A correlation value of 0.7487 from the Langmuir adsorption modeling was also obtained, pointing to an advantageous adsorption behavior. This research demonstrates how effectively anodizing for aluminum alloy 2024 works with and without sealing, especially in a 3.5 % NaCl-corrosive environment

Effects of deep cryogenic treatment on microstructure, mechanical, and corrosion of ZK60 Mg alloy

This study aims to investigate the effects of deep cryogenic treatment combined with traditional heat treatment on the microstructural characteristics, mechanical properties, and corrosion performance of ZK60 magnesium alloy. Quasi-in-situ TEM testing also indicates that deep cryogenic treatment induces the formation of ultra-fine zinc-rich precipitates in the magnesium matrix. After solid solution treatment, materials with cryogenic treatment will retain significant internal stress, which promotes the subsequent precipitation of rod-like β′1 during aging. Microstructural analysis reveals that deep cryogenic treatment before solution treatment and artificial aging can significantly enhance the length and density of rod-like β′1 precipitates. The treated material shows improved strength while maintaining its original elongation rate. Due to the nanoscale precipitation-induced micro galvanic effect, the aged samples exhibit a higher corrosion rate. The abundance of micrometer-sized second phases in the untreated sample does not significantly accelerate the material's corrosion rate. The solution-treated samples show the weakest micro galvanic effect and the best corrosion resistance.

Revealing the composite fretting-corrosion mechanisms of Ti6Al4V alloy against zirconia-toughened alumina ceramic in simulated body fluid

The composite fretting-corrosion damage due to combinations of radial, tangential, rotational, and other fretting causes local adverse tissue reactions and failure of artificial joints. Previous studies have mainly focused on the single fretting mode, while ignoring the coupled effects of multimode fretting. The fretting-corrosion mechanisms between the components are not yet fully understood. In this study, the tangential-radial composite fretting was realized by applying a normal alternating load to the tangential fretting. The composite fretting corrosion behavior of zirconia toughened alumina ceramic/Ti6Al4V alloy used for the head-neck interface of an artificial hip joint under simulated body fluid was investigated. The effects of displacement and alternating load amplitude were considered. The alternating load amplitude was given by the maximum normal load and minimum normal load ratio R. The results showed that the composite fretting damage mechanisms of this pair were mainly abrasion and tribocorrosion. Cracking also existed under large displacement. The effect of alternating load on fretting corrosion was found to be mainly caused by changes in the contact area and instantaneous contact state. In addition, the alternating load during the composite fretting promoted the formation of the three-body layer in the contact area. A decrease in load ratio caused fretting to change from gross to partial slip. In the case of small displacement, the load ratio had little effect on the friction work or wear scar profile. The corrosion rate of materials and the concentration of metal ions released into the solution increased as load ratio decreased. In cases of large and medium displacement, load ratio reduction increased the friction work and expanded the wear scar. The reduction in load ratio also caused the corrosion rate of the material to increase and then decrease, and the metal ion concentration decreased.

Simulation research on near-neutral electrochemical corrosion of ferrite–pearlite pipeline steel

The problem of electrochemical corrosion of buried pipelines in near-neutral electrolytes leads to defects in or even fracture of oil and gas pipelines and the leakage of natural gas. Based on the principle of material diffusion and migration, the research object established an electrochemical corrosion model under the metallographic structure of pipes with ferritic–pearlitic pipeline steel. The results show that the most severe corrosion occurs at the center of the corrosion on the surface of the pipeline steel in a near-neutral corrosive environment. In addition, due to corrosion product accumulation, the material corrosion rate increased by about 38%. The electrolyte potential near the corrosion electrode is smaller, the ion concentration near the electrode is the highest, and the mass transfer phenomenon around the corrosion electrode is obvious. When the material undergoes metallographic corrosion, the corrosion is more severe. This research method can be used to predict the electrochemical corrosion occurring in the metal structure of buried pipelines and has some guidance for the assessment of the integrity of the external surface of buried pipes.

Atmospheric corrosion rate prediction of low-alloy steel using machine learning models

Corrosion mitigation is one of the indispensable needs in many industries and is currently being pursued by various methods like surface modification, corrosion inhibitor addition, and cathodic protection systems. Corrosion rate prediction can help in designing alloys with an optimized composition of materials such that it has a lower corrosion rate in the environment where they are exposed. Corrosion rate prediction can also help the manufacturers to plan the replacement of the sample used in advance. Machine learning, which is the science of making machines learn without being explicitly programmed and without using pre-determined equations, can help overcome challenges in predicting corrosion of various materials under a variety of environmental conditions. In this paper, three machine learning algorithms namely Support Vector Regression, Multiple Linear Regression, and Random Forest Regression are used to develop a Hybrid model to predict the corrosion rate of materials. Feature reduction is performed after feature importance calculation using Random Forest Regression model. The accuracy of the developed models were calculated using r2 scores as an evaluation metric for different train-test split ratios. The input data for various conditions such as open, sheltered, coastal. Etc. are fed to the model and the performance was evaluated. The results show that the proposed Hybrid model outperforms the other baseline approaches with an accuracy of 91.46%, for predicting corrosion rate of materials.

Corrosion Behavior of Super Austenitic Stainless Steel, Duplex 2205 and 316L in Sulfamic Acid Environment

Currently, sulfamic acid as a primary chemical industrial material is ubiquitous. One of its uses is a sweetener. Due to its corrosive nature, it is necessary to use a suitable container to avoid contamination of the solution. Corrosion behavior of super austenitic stainless steel, duplex 2205, and 316L uncovered to sulfamic acid in diverse attention at ambient temperature had been investigated. Concentration Weight loss method, Potentiodynamic Polarization, and Electrochemical Impedance Spectroscopy (EIS) examined the corrosion rate. The result showed that the corrosion rate of material increased with the increasing concentration of sulfamic acid. Super austenitic stainless steel has higher corrosion resistance than duplex 2205 and 316L.

STUDY OF NEGATIVE INFLUENCE OF PETROLEUM PRODUCTS ON METAL ELEMENTS OF RAILWAY INFRASTRUCTURE

Purpose. The main purpose of the work is to improve the safety of railway transport operation. The implementation of this purpose is provided by assessing and preventing the negative influence of petroleum products on the structural elements of the railway infrastructure. Methodology. The main criterion for assessing the residual life of technical elements of equipment is their strength characteristics. One of the key factors affecting the suitability of technical devices during operation is corrosion damage to the metal. Therefore, the influence of various combinations of the mineralization degree and concentration of petroleum products on the corrosion rate of metals most often used in the design of cooling systems for diesel engines and other transport objects was studied. Thus, for carrying out static and dynamic laboratory tests, model working solutions with different salinity (demineralization model) and different concentrations of dissolved petroleum products (model of standard solutions with organic impurities) were selected. Dynamic and static studies of corrosion damage were carried out by the gravimetric method and the method of polarization resistance using standard samples and solutions. Findings. Based on the results of experimental studies of the authors and analytical data processing, generalizing model dependences of the corrosion rate on the mineralization degree of the working solution of the fractional composition of petroleum products were obtained. A study was carried out and the influence of the water demineralization degree on the corrosion rate of materials of diesel cooling systems was established. Originality. Based on a wide range of author's experimental data, the presence of generalizing dependences of the corrosion rate on temperature, the mineralization degree of the working solution and the fraction of the petroleum products composition has been shown and proven. The obtained dependences form the basis of the developed mathematical model of corrosion, which is a set of relationships linking the characteristics of the corrosion process with various factors influencing its development. Practical value. The obtained experimental and analytical data can be widely used for non-destructive testing procedures, detailed prediction of the state of structural elements and the selection of effective inhibitors to reduce the corrosive aggressiveness of the environment and protect structures.

Corrosion Behavior of LENS Deposited CoCrMo Alloy Using Bayesian Regularization-Based Artificial Neural Network (BRANN)

The well-known fact of metallurgy is that the lifetime of a metal structure depends on the material's corrosion rate. Therefore, applying an appropriate prediction of corrosion process for the manufactured metals or alloys trigger an extended life of the product. At present, the current prediction models for additive manufactured alloys are either complicated or built on a restricted basis towards corrosion depletion. This paper presents a novel approach to estimate the corrosion rate and corrosion potential prediction by considering significant major parameters such as solution time, aging time, aging temperature, and corrosion test time. The Laser Engineered Net Shaping (LENS), which is an additive manufacturing process used in the manufacturing of health care equipment, was investigated in the present research. All the accumulated information used to manufacture the LENS-based Cobalt-Chromium-Molybdenum (CoCrMo) alloy was considered from previous literature. They enabled to create a robust Bayesian Regularization (BR)-based Artificial Neural Network (ANN) in order to predict with accuracy the material best corrosion properties. The achieved data were validated by investigating its experimental behavior. It was found a very good agreement between the predicted values generated with the BRANN model and experimental values. The robustness of the proposed approach allows to implement the manufactured materials successfully in the biomedical implants.

Estimation of casing material corrosion rates for supercritical geothermal development

Supercritical geothermal development method has been proposed to increase the use of geothermal resources; the associated challenges include high temperatures and pressures, as well as an acidic environment, which increase the corrosion rate of casing materials. Here, we estimated material corrosion rates assuming that the temperature and pressure in a developmental environment were 500 °C and 60 MPa, respectively. Wells WD-1a in the Kakkonda geothermal field, Japan, and Icelandic Deep Drilling Program-1 (IDDP-1) were used as model cases for the concentrations of volcanic gasses. Geochemical calculations were conducted to obtain distributions of pH values from room temperature to 500 °C at 60 MPa. Corrosion rate distributions for the metallic materials were derived for the temperature recovery period after drilling and production and post-production periods inside the well. Consequently, the pH remained approximately constant at temperatures ≤ 300 °C and increased as the temperature exceeded 300 °C. In the supercritical temperature and pressure region, the pH increased as the pressure decreased, and it maximized at a 0.35 g/cm3 fluid density. The IDDP-1 model exhibited lower pH values than the WD-1a model; the H2S/CO2 ratio and HCl gas also increased. Furthermore, from room temperature to 300 °C, the corrosion rates were found to increase with the temperature and maximized in the subcritical regions at 300–350 °C. The corrosion rates then decreased as the temperature increased in the supercritical temperature regions. In the possible developmental processes, the corrosion rates tended to be high at temperature of 300–350 °C (~2,000 m) during the temperature recovery period after drilling, whereas the corrosion rates tended to increase near the wellhead during fluid production. The corrosion rate maximized near the wellhead immediately after the production period ceased at a well depth of 1,000–1,500 m the following week.

Electrochemical Noise and Polarization Analyses on Corrosion of Al-Brass Alloy During Erosion-Corrosion

It is known that impingement of solid particles on the surface of alloys could cause an increase in corrosion rate during erosion-corrosion. The increase in corrosion rate by erosion could be studied using the common electrochemical technique of polarization. Electrochemical noise method, on the other hand, has been widely used to study the localized corrosion. This technique could provide useful data on the effect of single particle impact on the corrosion rate of materials. In the present paper, both techniques of polarization and electrochemical noise were used to study the corrosion behavior of Al-brass alloy during erosion-corrosion. The erosion-enhanced corrosion rate was calculated and the results obtained from these two techniques were compared. The erosion-corrosion tests were performed at various sand concentrations of 0–30 g/l and different particle sizes. Under sand concentrations lower than 10 g/l, the electrochemical noise technique as a proper method for analysis of localized corrosion showed higher accuracy in measuring the erosion-enhanced corrosion as compared with the polarization method. However, at the concentrated slurries, higher possibility of simultaneous impacts and, therefore, overlapping of the current peaks imposed some limitation for the electrochemical noise method. The polarization and noise analyses revealed that an increase in the particle size resulted in an increase up to 2.8 times in the erosion-enhanced corrosion rate of the alloy.

THE EFFECT OF WELDING CURRENT ON AISI 1045 STRENGTH AND CORROSION RATE

Shielded Metal Arc Welding (SMAW) was widely used in industry for joining AISI 1045 steel because this method was simple, in-expensive, and the device is portable. This researched aimed to analyze the effect of variations in welding current towards material strength and corrosion rate of AISI 1045. Welding current that been used as variations in this study are 100, 110, and 120 Ampere. This research was conducted using tensile test on the weld area and immersion around the weld area in NaCl solution with 0.4% concentration. From the research that conducted, it is known that increasing in welding current made the yield strength, tensile strength, and fracture strength of material also increased. This phenomenon also happened for elongation of material in weld area. With increasing the welding current then the elongation of material also increasing. Another aspect that researched in this paper is the effect of welding current toward corrosion rate of material. From the result, it was known that increasing welding current made corrosion rate of material became faster.

Experimental Study on Corrosion Performance of Oil Tubing Steel in HPHT Flowing Media Containing O2 and CO2.

The high pressure and high temperature (HPHT) flow solution containing various gases and Cl− ions is one of the corrosive environments in the use of oilfield tubing and casing. The changing external environment and complex reaction processes are the main factors restricting research into this type of corrosion. To study the corrosion mechanism in the coexistence of O2 and CO2 in a flowing medium, a HPHT flow experiment was used to simulate the corrosion process of N80 steel in a complex downhole environment. After the test, the material corrosion rate, surface morphology, micromorphology, and corrosion product composition were tested. Results showed that corrosion of tubing material in a coexisting environment was significantly affected by temperature and gas concentration. The addition of O2 changes the structure of the original CO2 corrosion product and the corrosion process, thereby affecting the corrosion law, especially at high temperatures. Meanwhile, the flowing boundary layer and temperature changed the gas concentration near the wall, which changed the corrosion priority and intermediate products on the metal surface. These high temperature corrosion conclusions can provide references for the anticorrosion construction work of downhole pipe strings.

LIFUS II corrosion loop final design and screening of an Al based diffusion coating in stagnant LLE environment

Corrosion phenomena of structural material in Lead-Lithium Eutectic (LLE) environment is influenced by the coolant chemistry, temperature, velocity profile and impurities concentration dissolved in it. In the framework of the EUROfusion consortium, the Experimental Engineering Division (FSN-ING) by the ENEA Brasimone Research Centre (RC) is developing scientific activities to investigate the corrosion rate of materials and to test Al based diffusion coating at 550 °C, different velocities (0.01, 0.1 and 1 m/s) and different exposure times. To this end, a new experimental facility, named LIFUS II (Lithium for Fusion II) is under construction at the Brasimone RC laboratories. Piping and components installed in the hot leg of the facility are internally coated by an Al based diffusion coating developed in collaboration with RINA Consulting-CSM to reduce concentration of corrosion product in the loop. A preliminary screening of the coating was performed in LLE stagnant conditions at 550 °C for 1000 h showing a good resistance and no signs of dissolution were detected. The only modification on the surface was found to be related to the formation of dark islands made of Al2O3.