The advancement of nanotechnology has had an impact on the use of heat exchangers. Nanocoolants, which offer higher thermal efficiency than traditional coolants, have paid significant attention. These innovative fluids, which contain nanomaterials, not only have better heat efficiency but also improve energy efficiency compared to regular coolants. However, the presence of solid nanoparticles in the coolant may cause corrosion and erosion of tubes, leading to massive degradation of those parts. To evaluate the effectiveness of nanocoolant particles, this research was conducted by studying the impact of using nanocoolant on erosion-corrosion occurring on metal surfaces. The study focused on the erosion-corrosion of stainless steel (AISI 316) in coolant solutions containing nanoparticles. The experiments utilized a rotating cylinder electrode (RCE) with rotational speeds ranging from 0 to 1800 rpm and a temperature range of 30°C-70°C. The corrosion rate was determined using the linear polarization resistance (LPR) method, while the erosion was measured by calculating the average surface roughness of the samples. The design of the experiment (DOE) was utilized to find the mathematical expressions of the effects of the nanocoolant on erosion and corrosion. The findings revealed that the corrosion rate and surface roughness of the samples increased with an increase in temperature and rotation speed. Furthermore, the erosion-corrosion effects of the nanocoolant were less significant in stagnant conditions than in flow conditions, and significant differences were observed when compared with conventional coolant. Additionally, synergistic erosion and corrosion processes were detected at higher temperatures and higher rotation speeds for both types of coolants.
{"title":"Empirical Study of the Effect of Nanocoolant Particles on Corrosion Rate of 316 Stainless Steel","authors":"Yuli Panca Asmara, Jeya gopi Raman, Suparjo, Firda Herlina, Yap Chun Wei","doi":"10.1155/2024/5577674","DOIUrl":"https://doi.org/10.1155/2024/5577674","url":null,"abstract":"The advancement of nanotechnology has had an impact on the use of heat exchangers. Nanocoolants, which offer higher thermal efficiency than traditional coolants, have paid significant attention. These innovative fluids, which contain nanomaterials, not only have better heat efficiency but also improve energy efficiency compared to regular coolants. However, the presence of solid nanoparticles in the coolant may cause corrosion and erosion of tubes, leading to massive degradation of those parts. To evaluate the effectiveness of nanocoolant particles, this research was conducted by studying the impact of using nanocoolant on erosion-corrosion occurring on metal surfaces. The study focused on the erosion-corrosion of stainless steel (AISI 316) in coolant solutions containing nanoparticles. The experiments utilized a rotating cylinder electrode (RCE) with rotational speeds ranging from 0 to 1800 rpm and a temperature range of 30°C-70°C. The corrosion rate was determined using the linear polarization resistance (LPR) method, while the erosion was measured by calculating the average surface roughness of the samples. The design of the experiment (DOE) was utilized to find the mathematical expressions of the effects of the nanocoolant on erosion and corrosion. The findings revealed that the corrosion rate and surface roughness of the samples increased with an increase in temperature and rotation speed. Furthermore, the erosion-corrosion effects of the nanocoolant were less significant in stagnant conditions than in flow conditions, and significant differences were observed when compared with conventional coolant. Additionally, synergistic erosion and corrosion processes were detected at higher temperatures and higher rotation speeds for both types of coolants.","PeriodicalId":13893,"journal":{"name":"International Journal of Corrosion","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141008330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abdou Khadir Dia, Axel Gambou Bosca, Nadia Ghazzali
The study of pipeline corrosion is crucial to prevent economic losses, environmental degradation, and worker safety. In this study, several machine learning methods such as recursive feature elimination (RFE), principal component analysis (PCA), gradient boosting method (GBM), support vector machine (SVM), random forest (RF), K-nearest neighbors (KNN), and multilayer perceptron (MLP) were used to estimate the thickness loss of a slurry pipeline subjected to erosion corrosion. These different machine learning models were applied to the raw data (the set of variables), to the variables selected by RFE, and to the variables selected by PCA (principal components), and a comparative analysis was carried out to find out the influence of the selection and transformation of the data on the performance of the models. The results show that the models perform better on the variables selected by RFE and that the best models are RF, SVM, and GBM with an average RMSE of 0.017. By modifying the hyperparameters, the SVM model becomes the best model with an RMSE of 0.011 and an R-squared of 0.83.
{"title":"Walk-Through Corrosion Assessment of Slurry Pipeline Using Machine Learning","authors":"Abdou Khadir Dia, Axel Gambou Bosca, Nadia Ghazzali","doi":"10.1155/2024/9427747","DOIUrl":"https://doi.org/10.1155/2024/9427747","url":null,"abstract":"The study of pipeline corrosion is crucial to prevent economic losses, environmental degradation, and worker safety. In this study, several machine learning methods such as recursive feature elimination (RFE), principal component analysis (PCA), gradient boosting method (GBM), support vector machine (SVM), random forest (RF), K-nearest neighbors (KNN), and multilayer perceptron (MLP) were used to estimate the thickness loss of a slurry pipeline subjected to erosion corrosion. These different machine learning models were applied to the raw data (the set of variables), to the variables selected by RFE, and to the variables selected by PCA (principal components), and a comparative analysis was carried out to find out the influence of the selection and transformation of the data on the performance of the models. The results show that the models perform better on the variables selected by RFE and that the best models are RF, SVM, and GBM with an average RMSE of 0.017. By modifying the hyperparameters, the SVM model becomes the best model with an RMSE of 0.011 and an R-squared of 0.83.","PeriodicalId":13893,"journal":{"name":"International Journal of Corrosion","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140659499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. I. Hango, Lesley A. Cornish, J. W. van der Merwe, Lesley H. Chown
The Cr2O3 coating on the surface of ASTM A516 Grade 70 mild steel substrates was developed using the thermal plasma spraying process for protection against corrosion and wear. The microstructural behaviours for both coating and substrate were analysed using SEM and XRD techniques. The corrosion behaviours of the coatings and substrate in synthetic mine water with varying pH values (6, 3, and 1) were evaluated according to ASTM standards for potentiodynamic polarisation measurements. Tafel plots were drawn to determine the corrosion rates. Vickers hardness of the coatings and substrate were measured. The Cr2O3 coating exhibited cracks due to the solidification and cooling process, as well as some pores between the top and bonding layers caused by unmelted or partially melted particles. The corrosion tests revealed that a decrease in pH levels led to increased corrosion rates in both samples. The Cr2O3 coating demonstrated superior corrosion resistance, ranging from 0.036±0.003 mm/year to 0.110±0.004 mm/year, compared to the mild steel substrate, which ranged from 0.262±0.021 mm/year to 0.336±0.026 mm/year, across all pH values. Moreover, it exhibited significantly greater hardness (1260±77 HV3) than the mild steel substrate (180±14 HV3). The lower corrosion rates and higher hardness of Cr2O3 coating than the mild steel substrate make it a suitable coating in applications where corrosion resistance and high hardness properties are essential.
{"title":"Corrosion Behaviour of a Cr2O3 Coating on Mild Steel in Synthetic Mine Water","authors":"S. I. Hango, Lesley A. Cornish, J. W. van der Merwe, Lesley H. Chown","doi":"10.1155/2024/6343114","DOIUrl":"https://doi.org/10.1155/2024/6343114","url":null,"abstract":"The Cr2O3 coating on the surface of ASTM A516 Grade 70 mild steel substrates was developed using the thermal plasma spraying process for protection against corrosion and wear. The microstructural behaviours for both coating and substrate were analysed using SEM and XRD techniques. The corrosion behaviours of the coatings and substrate in synthetic mine water with varying pH values (6, 3, and 1) were evaluated according to ASTM standards for potentiodynamic polarisation measurements. Tafel plots were drawn to determine the corrosion rates. Vickers hardness of the coatings and substrate were measured. The Cr2O3 coating exhibited cracks due to the solidification and cooling process, as well as some pores between the top and bonding layers caused by unmelted or partially melted particles. The corrosion tests revealed that a decrease in pH levels led to increased corrosion rates in both samples. The Cr2O3 coating demonstrated superior corrosion resistance, ranging from 0.036±0.003 mm/year to 0.110±0.004 mm/year, compared to the mild steel substrate, which ranged from 0.262±0.021 mm/year to 0.336±0.026 mm/year, across all pH values. Moreover, it exhibited significantly greater hardness (1260±77 HV3) than the mild steel substrate (180±14 HV3). The lower corrosion rates and higher hardness of Cr2O3 coating than the mild steel substrate make it a suitable coating in applications where corrosion resistance and high hardness properties are essential.","PeriodicalId":13893,"journal":{"name":"International Journal of Corrosion","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140676300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. A. Nikolaychuk, Aleksandr Igorevich Biryukov, Artem Vladimirovich Sharov, L. O. Burmistrov, Natalya Sergeevna Amelina, Anastasia Andreevna Tereshkina
A compound 2-(6,8-dibromo-3-(4-hydroxycyclohexyl)-1,2,3,4-tetrahydroquinazolin-2-yl)phenol was synthetised from ambroxol hydrochloride and salicylaldehyde. The structure of the compound was studied with UV, IR, Raman, and 1H NMR spectroscopy. The inhibitory ability of the synthetised compound on the corrosion of mild stainless steel EN Fe37-3FN in 0.5 M hydrochloric acid solution was studied using gravimetric and electrochemical methods, including potentiodynamic polarisation and EIS. It was shown that the inhibitory activity of the compound increases with the increase of its concentration in a solution. An addition of 3 mg/l of the compound reduces the corrosion rate by 20% and that of 400 mg/l by 85%. The data of gravimetric and electrochemical measurements coincide well. The sorption of the compound on the metal surface obeys the Langmuir adsorption isotherm, and the nature of adsorption is physical. The compound exhibits the chelating activity with both ferrous and ferric ions in the acidic solution. The synthetised compound may be a good choice for the inhibition of steel corrosion in acidic environments.
一种化合物 2-(6,8-二溴-3-(4-羟基环己基)-1,2,3,4-四氢喹唑啉-2-基)苯酚由盐酸氨溴索和水杨醛合成。利用紫外光谱、红外光谱、拉曼光谱和 1H NMR 光谱研究了该化合物的结构。采用重量法和电化学法（包括电位极化和 EIS）研究了合成化合物在 0.5 M 盐酸溶液中对低碳钢 EN Fe37-3FN 的腐蚀抑制能力。研究表明，该化合物的抑制活性随着其在溶液中浓度的增加而增强。加入 3 毫克/升的化合物可使腐蚀速率降低 20%，加入 400 毫克/升的化合物可使腐蚀速率降低 85%。重量测量和电化学测量的数据非常吻合。该化合物在金属表面的吸附遵循 Langmuir 吸附等温线，吸附性质为物理吸附。该化合物在酸性溶液中与亚铁离子和铁离子都具有螯合活性。合成的化合物可能是在酸性环境中抑制钢铁腐蚀的良好选择。
{"title":"The Inhibitory Properties of the Ambroxol Derivative on the Corrosion of Mild Steel in Hydrochloric Acid Medium","authors":"P. A. Nikolaychuk, Aleksandr Igorevich Biryukov, Artem Vladimirovich Sharov, L. O. Burmistrov, Natalya Sergeevna Amelina, Anastasia Andreevna Tereshkina","doi":"10.1155/2024/2302202","DOIUrl":"https://doi.org/10.1155/2024/2302202","url":null,"abstract":"A compound 2-(6,8-dibromo-3-(4-hydroxycyclohexyl)-1,2,3,4-tetrahydroquinazolin-2-yl)phenol was synthetised from ambroxol hydrochloride and salicylaldehyde. The structure of the compound was studied with UV, IR, Raman, and 1H NMR spectroscopy. The inhibitory ability of the synthetised compound on the corrosion of mild stainless steel EN Fe37-3FN in 0.5 M hydrochloric acid solution was studied using gravimetric and electrochemical methods, including potentiodynamic polarisation and EIS. It was shown that the inhibitory activity of the compound increases with the increase of its concentration in a solution. An addition of 3 mg/l of the compound reduces the corrosion rate by 20% and that of 400 mg/l by 85%. The data of gravimetric and electrochemical measurements coincide well. The sorption of the compound on the metal surface obeys the Langmuir adsorption isotherm, and the nature of adsorption is physical. The compound exhibits the chelating activity with both ferrous and ferric ions in the acidic solution. The synthetised compound may be a good choice for the inhibition of steel corrosion in acidic environments.","PeriodicalId":13893,"journal":{"name":"International Journal of Corrosion","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140488991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Amoah, Sandyson Owusu-Poku, Gordon Asartenga Ajubala
In this study, radiographic techniques were used to inspect large-diameter pipes that are used for transporting fluids in some industries in Ghana. Radiographic approaches such as the double wall technique (DWT) and tangential radiographic technique (TRT) were used to evaluate the remaining wall thickness, deposits, and corrosion in the pipes. Two steel pipes with known varying wall thicknesses ranging from 4.00 mm to 13.00 mm with a diameter of 150.00 mm were examined to authenticate the accuracy and reliability of the tangential method that was used to measure the remaining wall thickness. The tangential configuration resulted in a higher material thickness, which therefore required more time of exposure compared to the DWT method. The exposure angle of the source to the tangential part of the specimen was approximately 87°. The film generated was compared with a normal pipe piece that was not machined to serve as a control. From the radiograph obtained, an average of 6 and 7 rounded indications depicting pitting corrosion were revealed on the radiograph of the internally and externally fabricated pipe, respectively. Radiographs after the TRT revealed that the recorded wall thickness obtained from the film is about twice the value of the calculated true wall thickness.
{"title":"Investigation of Wall Thickness, Corrosion, and Deposits in Industrial Pipelines Using Radiographic Technique","authors":"P. Amoah, Sandyson Owusu-Poku, Gordon Asartenga Ajubala","doi":"10.1155/2023/4924399","DOIUrl":"https://doi.org/10.1155/2023/4924399","url":null,"abstract":"In this study, radiographic techniques were used to inspect large-diameter pipes that are used for transporting fluids in some industries in Ghana. Radiographic approaches such as the double wall technique (DWT) and tangential radiographic technique (TRT) were used to evaluate the remaining wall thickness, deposits, and corrosion in the pipes. Two steel pipes with known varying wall thicknesses ranging from 4.00 mm to 13.00 mm with a diameter of 150.00 mm were examined to authenticate the accuracy and reliability of the tangential method that was used to measure the remaining wall thickness. The tangential configuration resulted in a higher material thickness, which therefore required more time of exposure compared to the DWT method. The exposure angle of the source to the tangential part of the specimen was approximately 87°. The film generated was compared with a normal pipe piece that was not machined to serve as a control. From the radiograph obtained, an average of 6 and 7 rounded indications depicting pitting corrosion were revealed on the radiograph of the internally and externally fabricated pipe, respectively. Radiographs after the TRT revealed that the recorded wall thickness obtained from the film is about twice the value of the calculated true wall thickness.","PeriodicalId":13893,"journal":{"name":"International Journal of Corrosion","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46505167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this work we investigated the inhibiting effect of sodium citrate, an environmentally safe corrosion inhibitor, on low-alloy steel 09G2S in a neutral environment using electrochemical methods. Potentiodynamic studies showed that sodium citrate reduces corrosion currents of 09G2S steel in a 0.1% NaCl solution and reaches its maximum efficiency at a concentration of 2.5 g/l. Electrochemical impedance spectroscopy results indicate the adsorption of citrate ions and the formation of a protective film, which probably consists of Fe-citrate complexes. The formation of a protective film on the steel surface in sodium citrate-inhibited solutions was confirmed by the results of scanning electron microscopy and EDX analysis. Hence, our research shows that sodium citrate has satisfactory anticorrosion properties and can be used as a basic component during the development of environmentally safe inhibitor compositions for the protection of low-alloyed carbon steels in neutral environments of recirculating water supply systems in petroleum refineries, petrochemical plants, and other industries.
{"title":"Sodium Citrate as an Environmentally Friendly Corrosion Inhibitor of Steel in a Neutral Environment","authors":"M. Danyliak, I. Zin, Yuliia Rizun, S. Korniy","doi":"10.1155/2022/1442537","DOIUrl":"https://doi.org/10.1155/2022/1442537","url":null,"abstract":"In this work we investigated the inhibiting effect of sodium citrate, an environmentally safe corrosion inhibitor, on low-alloy steel 09G2S in a neutral environment using electrochemical methods. Potentiodynamic studies showed that sodium citrate reduces corrosion currents of 09G2S steel in a 0.1% NaCl solution and reaches its maximum efficiency at a concentration of 2.5 g/l. Electrochemical impedance spectroscopy results indicate the adsorption of citrate ions and the formation of a protective film, which probably consists of Fe-citrate complexes. The formation of a protective film on the steel surface in sodium citrate-inhibited solutions was confirmed by the results of scanning electron microscopy and EDX analysis. Hence, our research shows that sodium citrate has satisfactory anticorrosion properties and can be used as a basic component during the development of environmentally safe inhibitor compositions for the protection of low-alloyed carbon steels in neutral environments of recirculating water supply systems in petroleum refineries, petrochemical plants, and other industries.","PeriodicalId":13893,"journal":{"name":"International Journal of Corrosion","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48238153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Based on the macrocell corrosion theory and by alternating the microcell corrosion state and macrocell corrosion state, the influence of mineral admixtures, such as fly ash, slag, and limestone powder, on the macrocell corrosion behaviors of steel bars embedded in chloride-contaminated concrete were investigated and clarified. The results indicated that the inhibition effect induced by slag on macrocell corrosion and microcell corrosion was obviously better than that induced by fly ash or limestone powder. The presence of slag in chloride-contaminated concrete could remarkably decrease the corrosion area ratios of anodic steel, even if the replacement levels of slag to cement reached 70%. With the addition of mineral admixtures into concrete, the ratio of macrocell current density to microcell current density was decreased to some extent, depending on the types, replacement levels, and replacement ways of mineral admixtures. The use of slag and fly ash in chloride-contaminated concrete can effectively weaken the macrocell corrosion and make the corrosion be dominated by microcell corrosion. The types and replacement levels of mineral admixtures also had a remarkable influence on the control mode of macrocell corrosion. The use of slag was more effective than that of fly ash or limestone to weaken the cathode control mode of macrocell corrosion and made the control mode of macrocell corrosion be dominated by jointed control.
{"title":"Effects of Mineral Admixtures on Macrocell Corrosion Behaviors of Steel Bars in Chloride-Contaminated Concrete","authors":"Z. Cao, Zhongfu Su, M. Hibino, H. Goda","doi":"10.1155/2022/3332123","DOIUrl":"https://doi.org/10.1155/2022/3332123","url":null,"abstract":"Based on the macrocell corrosion theory and by alternating the microcell corrosion state and macrocell corrosion state, the influence of mineral admixtures, such as fly ash, slag, and limestone powder, on the macrocell corrosion behaviors of steel bars embedded in chloride-contaminated concrete were investigated and clarified. The results indicated that the inhibition effect induced by slag on macrocell corrosion and microcell corrosion was obviously better than that induced by fly ash or limestone powder. The presence of slag in chloride-contaminated concrete could remarkably decrease the corrosion area ratios of anodic steel, even if the replacement levels of slag to cement reached 70%. With the addition of mineral admixtures into concrete, the ratio of macrocell current density to microcell current density was decreased to some extent, depending on the types, replacement levels, and replacement ways of mineral admixtures. The use of slag and fly ash in chloride-contaminated concrete can effectively weaken the macrocell corrosion and make the corrosion be dominated by microcell corrosion. The types and replacement levels of mineral admixtures also had a remarkable influence on the control mode of macrocell corrosion. The use of slag was more effective than that of fly ash or limestone to weaken the cathode control mode of macrocell corrosion and made the control mode of macrocell corrosion be dominated by jointed control.","PeriodicalId":13893,"journal":{"name":"International Journal of Corrosion","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2022-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42880288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PDL (Phoenix dactylifera leaves) is widely spread in Iraq and is known to be rich in phytochemicals as flavonoids, saponins, tannins, glycosides, oils, and lipids. The effect of PDL extract in reducing the corrosion of Aluminium in 1 M HCl solution using a weight loss technique, and computational chemistry calculations were investigated in this study. The study carried out at different temperatures (20, 30, 40, and 50) in the presence of plant extract and the absence of extract. A number of parameters were included to be detected in this study according to the density functional theory (DFT)/P3LYP/6-311G, including the highest occupied molecular orbital EHOMO, the lowest unoccupied molecular orbital ELUMO, energy gap Δ E , softness S , hardness η , dipole moment μ , electronegativity χ , electrophilicity ω , inhibitor-metal interaction energy ∆ ψ , and electrons transferred fraction Δ N . Two adsorption isotherms were used to explain inhibitor adsorption behavior. Two adsorption isotherms were used to explain inhibitor adsorption behavior, the Freundlich adsorption isotherm and the Langmuir adsorption isotherm, the Freundlich adsorption isotherm was discovered to be followed by the inhibitor with correlation coefficient values ranging from 0.98 to 0.94 with temperature increased from 20 to 50 degrees Celsius. The adsorption mechanism includes a physical adsorption process. The results showed that with the increment of the inhibitors concentration, there was an improvement of the inhibition efficiency. The most outstanding inhibitor efficiency was 97.7% at 10 mL/L inhibitor concentration.
PDL（Phoenix dactylifera leaves）在伊拉克广泛分布，富含黄酮、皂苷、单宁、糖苷、油和脂质等植物化学物质。PDL提取物降低铝在1中的腐蚀作用 M HCl溶液的重量损失技术和计算化学计算在本研究中进行了研究。该研究在不同温度（20、30、40和50）下，在存在植物提取物和不存在提取物的情况下进行。根据密度泛函理论（DFT）/P3LYP/6-311G，本研究包括了许多待检测的参数，包括最高占据分子轨道EHOMO、最低占据分子轨道ELUMO、能隙ΔE、柔软度S、硬度η、偶极矩μ、电负性χ、亲电性ω，抑制剂-金属相互作用能∆ψ和电子转移分数ΔN。用两条吸附等温线来解释缓蚀剂的吸附行为。使用两条吸附等温线来解释抑制剂的吸附行为，Freundlich吸附等温线和Langmuir吸附等温线，发现随着温度从20摄氏度增加到50摄氏度，Freundrich吸附等温线之后是抑制剂，相关系数在0.98到0.94之间。吸附机理包括物理吸附过程。结果表明，随着缓蚀剂浓度的增加，缓蚀效果有所提高。在10 mL/L抑制剂浓度。
{"title":"Computational and Experimental Evaluation of Inhibition Potential of a New Ecologically Friendly Inhibitor Leaves of Date Palm (Phoenix dactylifera L.) for Aluminium Corrosion in an Acidic Media","authors":"O. Hatem","doi":"10.1155/2022/5953561","DOIUrl":"https://doi.org/10.1155/2022/5953561","url":null,"abstract":"PDL (Phoenix dactylifera leaves) is widely spread in Iraq and is known to be rich in phytochemicals as flavonoids, saponins, tannins, glycosides, oils, and lipids. The effect of PDL extract in reducing the corrosion of Aluminium in 1 M HCl solution using a weight loss technique, and computational chemistry calculations were investigated in this study. The study carried out at different temperatures (20, 30, 40, and 50) in the presence of plant extract and the absence of extract. A number of parameters were included to be detected in this study according to the density functional theory (DFT)/P3LYP/6-311G, including the highest occupied molecular orbital EHOMO, the lowest unoccupied molecular orbital ELUMO, energy gap \u0000 \u0000 Δ\u0000 E\u0000 \u0000 , softness \u0000 \u0000 S\u0000 \u0000 , hardness \u0000 \u0000 η\u0000 \u0000 , dipole moment \u0000 \u0000 μ\u0000 \u0000 , electronegativity \u0000 \u0000 χ\u0000 \u0000 , electrophilicity \u0000 \u0000 ω\u0000 \u0000 , inhibitor-metal interaction energy \u0000 \u0000 ∆\u0000 ψ\u0000 \u0000 , and electrons transferred fraction \u0000 \u0000 Δ\u0000 N\u0000 \u0000 . Two adsorption isotherms were used to explain inhibitor adsorption behavior. Two adsorption isotherms were used to explain inhibitor adsorption behavior, the Freundlich adsorption isotherm and the Langmuir adsorption isotherm, the Freundlich adsorption isotherm was discovered to be followed by the inhibitor with correlation coefficient values ranging from 0.98 to 0.94 with temperature increased from 20 to 50 degrees Celsius. The adsorption mechanism includes a physical adsorption process. The results showed that with the increment of the inhibitors concentration, there was an improvement of the inhibition efficiency. The most outstanding inhibitor efficiency was 97.7% at 10 mL/L inhibitor concentration.","PeriodicalId":13893,"journal":{"name":"International Journal of Corrosion","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2022-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43596233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Popoola, A. Yusuff, O. Ikumapayi, Onyemaechi Melford Chima, A. Ogunyemi, B. A. Obende
In this study, corrosion inhibition efficiency of Cucumeropsis mannii shell extract (CMSE) was tested on A515 Grade 70 carbon steel in 1.0 M NaCl solution. Potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), and weight loss (WL) measurements were used to investigate the inhibition efficiency. Scanning electron microscopy, Fourier transform infrared spectroscopy, atomic adsorption spectroscopy, and energy dispersive spectroscopy were used to characterize the carbon steel and extract. PDP and EIS measurements revealed maximum inhibition efficiency of 91.2% and 92.2%, respectively. Tafel plot confirmed inhibitor to be a mixed type. A monolayer adsorption of CMSE molecules occurred spontaneously by physisorption. Polarization resistance increased with increasing inhibitor concentration. WL measurement revealed decrease in corrosion rate with increasing concentration of corrosion inhibitor. Maximum Young modulus and hardness of 202.4 GPa and 112.3 BHN, respectively, were recorded for the carbon steel at a minimum corrosion rate and load. Pitting and uniform corrosion were formed on the carbon steel in the absence of CMSE. CMSE contains –OH, –OCH3, and –C-NH3 as active functional groups. In conclusion, Cucumeropsis mannii shell extract acted excellently as corrosion inhibitor for A515 Grade 70 carbon steel in 1.0 M NaCl.
本研究以A515 70级碳钢为试材，在1.0 M NaCl溶液。使用电位动态极化（PDP）、电化学阻抗谱（EIS）和重量损失（WL）测量来研究抑制效率。利用扫描电子显微镜、傅立叶变换红外光谱、原子吸附光谱和能量色散光谱对碳钢和提取物进行了表征。PDP和EIS测量显示最大抑制效率分别为91.2%和92.2%。塔菲尔图证实抑制剂为混合型。CMSE分子的单层吸附通过物理吸附自发发生。极化电阻随抑制剂浓度的增加而增加。WL测量显示腐蚀速率随着缓蚀剂浓度的增加而降低。最大杨氏模量和硬度为202.4 在最小腐蚀速率和载荷下，碳钢分别记录了GPa和112.3BHN。在没有CMSE的情况下，碳钢上形成了点蚀和均匀腐蚀。CMSE含有–OH、–OCH3和–C-NH3作为活性官能团。综上所述，曼氏Cucumeropsis壳提取物对A515 70级碳钢在1.0 M NaCl。
{"title":"Electrochemical, Isotherm, and Material Strength Studies of Cucumeropsis mannii Shell Extract on A515 Grade 70 Carbon Steel in NaCl Solution","authors":"L. Popoola, A. Yusuff, O. Ikumapayi, Onyemaechi Melford Chima, A. Ogunyemi, B. A. Obende","doi":"10.1155/2022/3189844","DOIUrl":"https://doi.org/10.1155/2022/3189844","url":null,"abstract":"In this study, corrosion inhibition efficiency of Cucumeropsis mannii shell extract (CMSE) was tested on A515 Grade 70 carbon steel in 1.0 M NaCl solution. Potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), and weight loss (WL) measurements were used to investigate the inhibition efficiency. Scanning electron microscopy, Fourier transform infrared spectroscopy, atomic adsorption spectroscopy, and energy dispersive spectroscopy were used to characterize the carbon steel and extract. PDP and EIS measurements revealed maximum inhibition efficiency of 91.2% and 92.2%, respectively. Tafel plot confirmed inhibitor to be a mixed type. A monolayer adsorption of CMSE molecules occurred spontaneously by physisorption. Polarization resistance increased with increasing inhibitor concentration. WL measurement revealed decrease in corrosion rate with increasing concentration of corrosion inhibitor. Maximum Young modulus and hardness of 202.4 GPa and 112.3 BHN, respectively, were recorded for the carbon steel at a minimum corrosion rate and load. Pitting and uniform corrosion were formed on the carbon steel in the absence of CMSE. CMSE contains –OH, –OCH3, and –C-NH3 as active functional groups. In conclusion, Cucumeropsis mannii shell extract acted excellently as corrosion inhibitor for A515 Grade 70 carbon steel in 1.0 M NaCl.","PeriodicalId":13893,"journal":{"name":"International Journal of Corrosion","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2022-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47511657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xudong Zhou, Xinmin Zhang, Ruiwen Xu, Bin Li, X. Ren, Jinyang Zhu, Ying Jin
The corrosion tendency and fatigue behavior of a SM480C welded joint in a sea-crossing suspension bridge after twenty-year exposure to a marine environment was investigated in this work. It was found that the corrosion product on the whole surface of the welded joint is loose, with many holes and cracks, which allowing corrosive media enter and reach the surface of the substrate. Localized corrosion occurred in the weld zone (WZ) and the heat-affected zone (HAZ), the maximum depth of localized corrosion in the HAZ reached 1.8 mm, and the maximum local corrosion rate is 0.082 mm/y. By using Bimetallic Conjugation Theory calculations, the galvanic effect of the welded joint was qualified, indicates that HAZ was the most corrosion susceptible area in the welded joint. The galvanic corrosion current on HAZ reached approximately 2 μA, which is much higher than the corrosion of isolated HAZ by about 6.5 times. The corrosion has an obvious influence on the fatigue performance, the elongation of the bridge deck decreases by 40%~70%, and the tensile strength decreases by 4.5%~31.33%. In order to ensure the service safety and avoid premature failure, the average thickness of the corroded bridge deck should not be less than 10 mm under the stress amplitude of 115 MPa.
{"title":"Galvanic Corrosion and Fatigue Behavior of a SM480C Welded Joint Steel in a Sea-Crossing Suspension Bridge","authors":"Xudong Zhou, Xinmin Zhang, Ruiwen Xu, Bin Li, X. Ren, Jinyang Zhu, Ying Jin","doi":"10.1155/2022/2665663","DOIUrl":"https://doi.org/10.1155/2022/2665663","url":null,"abstract":"The corrosion tendency and fatigue behavior of a SM480C welded joint in a sea-crossing suspension bridge after twenty-year exposure to a marine environment was investigated in this work. It was found that the corrosion product on the whole surface of the welded joint is loose, with many holes and cracks, which allowing corrosive media enter and reach the surface of the substrate. Localized corrosion occurred in the weld zone (WZ) and the heat-affected zone (HAZ), the maximum depth of localized corrosion in the HAZ reached 1.8 mm, and the maximum local corrosion rate is 0.082 mm/y. By using Bimetallic Conjugation Theory calculations, the galvanic effect of the welded joint was qualified, indicates that HAZ was the most corrosion susceptible area in the welded joint. The galvanic corrosion current on HAZ reached approximately 2 μA, which is much higher than the corrosion of isolated HAZ by about 6.5 times. The corrosion has an obvious influence on the fatigue performance, the elongation of the bridge deck decreases by 40%~70%, and the tensile strength decreases by 4.5%~31.33%. In order to ensure the service safety and avoid premature failure, the average thickness of the corroded bridge deck should not be less than 10 mm under the stress amplitude of 115 MPa.","PeriodicalId":13893,"journal":{"name":"International Journal of Corrosion","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2022-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42088875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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