Pub Date : 2023-11-10DOI: 10.1515/corrrev-2023-0011
Irina S. Kazantseva, Feodor F. Chausov, Vasiliy L. Vorob’yov, Natalya V. Lomova, Alyona N. Maratkanova, Igor K. Averkiev
Abstract Corrosion-electrochemical behaviour of steel E 235 in borate buffer solution (pH = 7.4) containing F − ions with and with no added ZnNTP as an inhibitor, where NTP = N(CH 2 PO 3 ) 3 , was studied by the potentiodynamic polarization and depth-profiling XPS analysis of specimens polarized at different potentials applied. Depending on the potential applied, F − ion was shown to influence differently on the formation, composition and structure of passive film. At E < 0.1–0.2 V/SSCE, F − ion promotes the passivation via forming sparingly soluble FeF 2 , and the resulting film is comprised of mainly iron(II) oxides and hydroxides, as well as sparingly soluble FeF 2 and FeZnNTP. At E > 0.1–0.2 V/SSCE, F − ion works for the destruction of the passive film by forming soluble compounds with Fe 3+ ions, which leads to its thinning. ZnNTP inhibitor forms FeZnNTP heterometallic complex with iron ions, which is the most stable constituent of the passive film. When F − ion concentration does not exceed 1.4 mmol/L, ZnNTP inhibitor is optimal to be added in amount of 0.5–1.0 g/L, whereas concentrations of 5.6 mmol/L F − ion and higher require 5 g/L ZnNTP or even more to be added.
{"title":"Inhibition efficiency and mechanism of nitrilo-tris(methylenephosphonato)zinc on mild steel corrosion in neutral fluoride-containing aqueous media","authors":"Irina S. Kazantseva, Feodor F. Chausov, Vasiliy L. Vorob’yov, Natalya V. Lomova, Alyona N. Maratkanova, Igor K. Averkiev","doi":"10.1515/corrrev-2023-0011","DOIUrl":"https://doi.org/10.1515/corrrev-2023-0011","url":null,"abstract":"Abstract Corrosion-electrochemical behaviour of steel E 235 in borate buffer solution (pH = 7.4) containing F − ions with and with no added ZnNTP as an inhibitor, where NTP = N(CH 2 PO 3 ) 3 , was studied by the potentiodynamic polarization and depth-profiling XPS analysis of specimens polarized at different potentials applied. Depending on the potential applied, F − ion was shown to influence differently on the formation, composition and structure of passive film. At E < 0.1–0.2 V/SSCE, F − ion promotes the passivation via forming sparingly soluble FeF 2 , and the resulting film is comprised of mainly iron(II) oxides and hydroxides, as well as sparingly soluble FeF 2 and FeZnNTP. At E > 0.1–0.2 V/SSCE, F − ion works for the destruction of the passive film by forming soluble compounds with Fe 3+ ions, which leads to its thinning. ZnNTP inhibitor forms FeZnNTP heterometallic complex with iron ions, which is the most stable constituent of the passive film. When F − ion concentration does not exceed 1.4 mmol/L, ZnNTP inhibitor is optimal to be added in amount of 0.5–1.0 g/L, whereas concentrations of 5.6 mmol/L F − ion and higher require 5 g/L ZnNTP or even more to be added.","PeriodicalId":10721,"journal":{"name":"Corrosion Reviews","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135091772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-21DOI: 10.1515/corrrev-2022-0112
Dyari Mustafa Mamand, Twana Mohammed Kak Anwer, Hiwa Mohammad Qadr
Abstract 2,5-Bis(4-dimethylaminophenyl)-1,3,4-oxadiazole (DAPO), 2-acetylthiophene thiosemicarbazone (2-AT), 2-hydroxyphenyl-5-mercapto-1-oxa-3,4-diazole (HMO), and 2-cinnamyl-5-mercapto-1-oxa-3,4-diazole (CMO) have been studied by measurement several quantum chemical parameters such as E HOMO , E LUMO , bandgap energy, softness, hardness, electrophilicity, nucleophilicity, and Fukui function analysis. The best corrosion inhibition efficiency was evaluated through a comparison between theoretical and experimental results. In gas and aqueous phases, protonated and nonprotonated species were investigated for their electronic structures in order to discover the factors and reasons behind corrosion inhibition. A theoretical study of all the studied compounds in gas and aqueous phases was investigated by employing the density functional theory (DFT) at 6–311++G(d, p) basis set and Becke’s three parameters hybrid exchange–correlation functional (B3LYP). The molecules are calculated using quantum computational chemistry calculations such as Gaussian09 software. The experiments were carried out on carbon steel and HCL. Carbon steel is the most often used steel because it combines outstanding mechanical qualities with a low cost. One of the most commonly utilized agents for these purposes is HCl solution. On the other hand, steel and ferrous alloys are likely to corrode under certain conditions. One of the most effective strategies for protecting metals against corrosion is corrosion inhibitors, and they are becoming more common.
{"title":"Corrosion inhibition performance of organic compounds and theoretical calculations based on density functional theory (DFT)","authors":"Dyari Mustafa Mamand, Twana Mohammed Kak Anwer, Hiwa Mohammad Qadr","doi":"10.1515/corrrev-2022-0112","DOIUrl":"https://doi.org/10.1515/corrrev-2022-0112","url":null,"abstract":"Abstract 2,5-Bis(4-dimethylaminophenyl)-1,3,4-oxadiazole (DAPO), 2-acetylthiophene thiosemicarbazone (2-AT), 2-hydroxyphenyl-5-mercapto-1-oxa-3,4-diazole (HMO), and 2-cinnamyl-5-mercapto-1-oxa-3,4-diazole (CMO) have been studied by measurement several quantum chemical parameters such as E HOMO , E LUMO , bandgap energy, softness, hardness, electrophilicity, nucleophilicity, and Fukui function analysis. The best corrosion inhibition efficiency was evaluated through a comparison between theoretical and experimental results. In gas and aqueous phases, protonated and nonprotonated species were investigated for their electronic structures in order to discover the factors and reasons behind corrosion inhibition. A theoretical study of all the studied compounds in gas and aqueous phases was investigated by employing the density functional theory (DFT) at 6–311++G(d, p) basis set and Becke’s three parameters hybrid exchange–correlation functional (B3LYP). The molecules are calculated using quantum computational chemistry calculations such as Gaussian09 software. The experiments were carried out on carbon steel and HCL. Carbon steel is the most often used steel because it combines outstanding mechanical qualities with a low cost. One of the most commonly utilized agents for these purposes is HCl solution. On the other hand, steel and ferrous alloys are likely to corrode under certain conditions. One of the most effective strategies for protecting metals against corrosion is corrosion inhibitors, and they are becoming more common.","PeriodicalId":10721,"journal":{"name":"Corrosion Reviews","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136235473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-18DOI: 10.1515/corrrev-2023-0020
Sisi Liu, Yicun Wang, Hualiang Huang, Gangliang Huang
Abstract Magnesium alloy is one of the most promising automotive lightweight materials, but its poor corrosion resistance seriously hinders its practical application in automotive engines. Corrosion inhibitor technology has the characteristics of small dosage, simple operation, low cost, and does not affect the heat dissipation of metals. Therefore, adding high-efficiency long-term corrosion inhibitors to automotive engine coolants is the simplest, most practical and effective way to realize the application of magnesium alloy in automotive engines. This paper reviewed the corrosion and corrosion inhibition behaviors of magnesium alloy in ethylene glycol aqueous solution. The effects of temperature, galvanic effect, water content, and anionic and acidic oxides on the corrosion of magnesium alloy in automotive coolant were summarized. The research, advantages and disadvantages of inorganic, organics small-molecule, polymer, and composite corrosion inhibitors for inhibiting the corrosion of magnesium alloy in ethylene glycol aqueous solution were also summarized. The construction of inorganic-polymer corrosion inhibitor composite films was proposed to realize the application of magnesium alloy in engine, which further enriched the corrosion theories and anti-corrosion technologies of magnesium alloy.
{"title":"A review on corrosion and corrosion inhibition behaviors of magnesium alloy in ethylene glycol aqueous solution","authors":"Sisi Liu, Yicun Wang, Hualiang Huang, Gangliang Huang","doi":"10.1515/corrrev-2023-0020","DOIUrl":"https://doi.org/10.1515/corrrev-2023-0020","url":null,"abstract":"Abstract Magnesium alloy is one of the most promising automotive lightweight materials, but its poor corrosion resistance seriously hinders its practical application in automotive engines. Corrosion inhibitor technology has the characteristics of small dosage, simple operation, low cost, and does not affect the heat dissipation of metals. Therefore, adding high-efficiency long-term corrosion inhibitors to automotive engine coolants is the simplest, most practical and effective way to realize the application of magnesium alloy in automotive engines. This paper reviewed the corrosion and corrosion inhibition behaviors of magnesium alloy in ethylene glycol aqueous solution. The effects of temperature, galvanic effect, water content, and anionic and acidic oxides on the corrosion of magnesium alloy in automotive coolant were summarized. The research, advantages and disadvantages of inorganic, organics small-molecule, polymer, and composite corrosion inhibitors for inhibiting the corrosion of magnesium alloy in ethylene glycol aqueous solution were also summarized. The construction of inorganic-polymer corrosion inhibitor composite films was proposed to realize the application of magnesium alloy in engine, which further enriched the corrosion theories and anti-corrosion technologies of magnesium alloy.","PeriodicalId":10721,"journal":{"name":"Corrosion Reviews","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135109781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-11DOI: 10.1515/corrrev-2023-0031
D. M. Mamad, R. Omer, K. Othman
Abstract Anti-corrosion properties of L-lysine (Lys), S-methyl (S-Met), L-cysteine (Cys), L-glycine (Gly), valinin (Val), and L-glutamine (Glu), all of which are amino acids, were evaluated on the surfaces of iron, copper, and aluminum in both the protonated and non-protonated states in both the gas and aqueous phases at their optimal symmetry. Analysis was performed based on density functional theory (DFT) calculation at 6-311++G(d,p) and B3LYP level. Monte Carlo simulation generated top and side views of the most energetically stable configuration for the adsorption of all selected amino acids on Al (110), Fe (110), and Cu (110). This suggests that the Monte Carlo simulation was able to accurately predict the adsorption properties of the amino acids on the selected metal surfaces. Glu was found to be the strongest inhibitor amongst the six molecules tested, as it had the lowest energy difference and the highest reactivity, according to the decreasing sequence of ∆E values. Electronegativity difference of the compounds investigated from highest to lowest is Lys, S-Met, Cyst, Gly, Val, and Glu. This order is also reflected in the polarizability of the compounds, with Lys having the highest polarizability and Glu having the lowest, suggesting that Glu may have the highest inhibitory efficacy.
{"title":"Quantum chemical analysis of amino acids as anti-corrosion agents","authors":"D. M. Mamad, R. Omer, K. Othman","doi":"10.1515/corrrev-2023-0031","DOIUrl":"https://doi.org/10.1515/corrrev-2023-0031","url":null,"abstract":"Abstract Anti-corrosion properties of L-lysine (Lys), S-methyl (S-Met), L-cysteine (Cys), L-glycine (Gly), valinin (Val), and L-glutamine (Glu), all of which are amino acids, were evaluated on the surfaces of iron, copper, and aluminum in both the protonated and non-protonated states in both the gas and aqueous phases at their optimal symmetry. Analysis was performed based on density functional theory (DFT) calculation at 6-311++G(d,p) and B3LYP level. Monte Carlo simulation generated top and side views of the most energetically stable configuration for the adsorption of all selected amino acids on Al (110), Fe (110), and Cu (110). This suggests that the Monte Carlo simulation was able to accurately predict the adsorption properties of the amino acids on the selected metal surfaces. Glu was found to be the strongest inhibitor amongst the six molecules tested, as it had the lowest energy difference and the highest reactivity, according to the decreasing sequence of ∆E values. Electronegativity difference of the compounds investigated from highest to lowest is Lys, S-Met, Cyst, Gly, Val, and Glu. This order is also reflected in the polarizability of the compounds, with Lys having the highest polarizability and Glu having the lowest, suggesting that Glu may have the highest inhibitory efficacy.","PeriodicalId":10721,"journal":{"name":"Corrosion Reviews","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2023-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49646956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-05DOI: 10.1515/corrrev-2023-0017
Leonardo X. Alvarez, Oladis Troconis de Rincón, Jorge Escribano, B. R. Rincon Troconis
Abstract With the goal of preventing concrete deterioration by means of destructive corrosion processes, the use of single organic compounds or mixtures as organic corrosion inhibitors (OCIs) instead of inorganic chemicals is becoming a very attractive practice. As OCIs are more ecologically friendly in their production and environmental fate, they have several advantages over well-known inorganic additives such as metallic nitrites, chromates, or arsenates. In this article, the application of different single organic compounds (of either natural or synthetic origin) as well as mixtures that have been used to lengthen the lifespan of concrete structures is reviewed. After a small exemplification of the use of single organic compounds bearing amino, hydroxy, formyl, or carboxylic functionalities, the more often used OCIs are reviewed according to their principal functional group. Afterward, the application of compound mixtures of either synthetic or natural origin, the use of natural extracts, and biomass are surveyed. Finally, the effects of functional groups within the top 10 inhibitor molecules, the toxicity of OCIs, their effects on the physical-mechanical properties of concrete, and their long-term performance are discussed.
{"title":"Organic compounds as corrosion inhibitors for reinforced concrete: a review","authors":"Leonardo X. Alvarez, Oladis Troconis de Rincón, Jorge Escribano, B. R. Rincon Troconis","doi":"10.1515/corrrev-2023-0017","DOIUrl":"https://doi.org/10.1515/corrrev-2023-0017","url":null,"abstract":"Abstract With the goal of preventing concrete deterioration by means of destructive corrosion processes, the use of single organic compounds or mixtures as organic corrosion inhibitors (OCIs) instead of inorganic chemicals is becoming a very attractive practice. As OCIs are more ecologically friendly in their production and environmental fate, they have several advantages over well-known inorganic additives such as metallic nitrites, chromates, or arsenates. In this article, the application of different single organic compounds (of either natural or synthetic origin) as well as mixtures that have been used to lengthen the lifespan of concrete structures is reviewed. After a small exemplification of the use of single organic compounds bearing amino, hydroxy, formyl, or carboxylic functionalities, the more often used OCIs are reviewed according to their principal functional group. Afterward, the application of compound mixtures of either synthetic or natural origin, the use of natural extracts, and biomass are surveyed. Finally, the effects of functional groups within the top 10 inhibitor molecules, the toxicity of OCIs, their effects on the physical-mechanical properties of concrete, and their long-term performance are discussed.","PeriodicalId":10721,"journal":{"name":"Corrosion Reviews","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41994478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-21DOI: 10.1515/corrrev-2023-0027
Zhenchang Xu, Kuirong Liu, Bill Gu, Luchun Yan, X. Pang, K. Gao
Abstract Deep learning algorithm has a wide range of applications and excellent performance in the field of engineering image recognition. At present, the detection and recognition of buried metal pipeline defects still mainly rely on manual work, which is inefficient. In order to realize the intelligent and efficient recognition of pipeline magnetic flux leakage (MFL) inspection images, based on the actual demand of MFL inspection, this paper proposes a new object detection framework based on YOLOv5 and CNN models in deep learning. The framework first uses object detection to classify the targets in MFL images and then inputs the features containing defects into a regression model based on CNN according to the classification results. The framework integrates object detection and image regression model to realize the target classification of MFL pseudo color map and the synchronous recognition of metal loss depth. The results show that the target recognition ability of the model is good, its precision reaches 0.96, and the mean absolute error of the metal loss depth recognition result is 1.14. The framework has more efficient identification ability and adaptability and makes up for the quantification of damage depth, which can be used for further monitoring and maintenance strategies.
{"title":"Image recognition model of pipeline magnetic flux leakage detection based on deep learning","authors":"Zhenchang Xu, Kuirong Liu, Bill Gu, Luchun Yan, X. Pang, K. Gao","doi":"10.1515/corrrev-2023-0027","DOIUrl":"https://doi.org/10.1515/corrrev-2023-0027","url":null,"abstract":"Abstract Deep learning algorithm has a wide range of applications and excellent performance in the field of engineering image recognition. At present, the detection and recognition of buried metal pipeline defects still mainly rely on manual work, which is inefficient. In order to realize the intelligent and efficient recognition of pipeline magnetic flux leakage (MFL) inspection images, based on the actual demand of MFL inspection, this paper proposes a new object detection framework based on YOLOv5 and CNN models in deep learning. The framework first uses object detection to classify the targets in MFL images and then inputs the features containing defects into a regression model based on CNN according to the classification results. The framework integrates object detection and image regression model to realize the target classification of MFL pseudo color map and the synchronous recognition of metal loss depth. The results show that the target recognition ability of the model is good, its precision reaches 0.96, and the mean absolute error of the metal loss depth recognition result is 1.14. The framework has more efficient identification ability and adaptability and makes up for the quantification of damage depth, which can be used for further monitoring and maintenance strategies.","PeriodicalId":10721,"journal":{"name":"Corrosion Reviews","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2023-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47793814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-15DOI: 10.1515/corrrev-2023-0064
Lin Sun, Deqing Ma, Ye Liu, Q. Qin, Liang Liang, Hongbin Ma, Fuan Wei, Chao Zhang
Abstract X-ray photoelectron spectroscopy (XPS) combined with Ar ion etching was used to analyse the surface film of pure Mg at different depth after immersion in 3.5 % NaCl solution for 10 min. The XPS spectra of specimen surface showed that the corrosion products are mainly made up of Mg(OH)2 and Mg2Cl(OH)3·xH2O. The formation process of Mg2Cl(OH)3 is the reaction of Mg(OH)2 and Cl− and H+ in weak acidic solutions. The XPS results indicated that the intensities of Mg2Cl(OH)3·xH2O decreased with the increase of etching time from 0 s to 4680 s. It is confirmed that the edge of Mg(OH)2 protrudes outward and then splits into Mg2Cl(OH)3 when Cl− attacks the Mg(OH)2 films, so the Mg2Cl(OH)3 attached to Mg(OH)2. Meanwhile, coupling the scanning electron microscope (SEM) and transmission electron microscopy (TEM) with the XPS to analyze the corrosion mechanism. Furthermore, the results displayed that the XPS combined with Ar ion etching is a good characterization method to understand the reaction of corrosion products.
{"title":"Determination of corrosion product film on pure Mg in Cl− environment using XPS etching","authors":"Lin Sun, Deqing Ma, Ye Liu, Q. Qin, Liang Liang, Hongbin Ma, Fuan Wei, Chao Zhang","doi":"10.1515/corrrev-2023-0064","DOIUrl":"https://doi.org/10.1515/corrrev-2023-0064","url":null,"abstract":"Abstract X-ray photoelectron spectroscopy (XPS) combined with Ar ion etching was used to analyse the surface film of pure Mg at different depth after immersion in 3.5 % NaCl solution for 10 min. The XPS spectra of specimen surface showed that the corrosion products are mainly made up of Mg(OH)2 and Mg2Cl(OH)3·xH2O. The formation process of Mg2Cl(OH)3 is the reaction of Mg(OH)2 and Cl− and H+ in weak acidic solutions. The XPS results indicated that the intensities of Mg2Cl(OH)3·xH2O decreased with the increase of etching time from 0 s to 4680 s. It is confirmed that the edge of Mg(OH)2 protrudes outward and then splits into Mg2Cl(OH)3 when Cl− attacks the Mg(OH)2 films, so the Mg2Cl(OH)3 attached to Mg(OH)2. Meanwhile, coupling the scanning electron microscope (SEM) and transmission electron microscopy (TEM) with the XPS to analyze the corrosion mechanism. Furthermore, the results displayed that the XPS combined with Ar ion etching is a good characterization method to understand the reaction of corrosion products.","PeriodicalId":10721,"journal":{"name":"Corrosion Reviews","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2023-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45860279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract In this study, the resistance of S30432 to low-alkali coal ash corrosion in a high-efficiency USC boiler was investigated. Currently, S30432 is widely used in the high-temperature superheater and reheater of boilers burning low-alkali and high-sulfur coal. During the experiment, S30432 coated with low-alkali coal ash were fixed in a high-temperature tubular reactor, and hot gas at 650 °C and 700 °C containing SO2 passed over the specimens for 2000 h. Then the specimens were tested by X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. It was found that S30432 specimens mainly underwent high-temperature oxidation. For the gas temperature of 700 °C and SO2 volume concentration of 0.35 %, the sulfidation reaction occurred and the weight change was only 1.08 mg cm−2. The results show that there is no obvious high-temperature corrosion after three years of operation of a 700 MW 620 °C boiler. The results are in contrast with the high-alkali coal ash corrosion resistance of S30432. It is concluded that S30432 can meet the requirements of a high-efficiency USC boiler burning low-alkali and high-sulfur coal.
{"title":"High-temperature corrosion behavior of S30432 in high-efficiency ultra-supercritical boiler burning low-alkali and high-sulfur coal","authors":"Yugang Liu, Yinhe Liu, Chunhong Mo, Shenming Ran, Chaoqiang Yin","doi":"10.1515/corrrev-2022-0065","DOIUrl":"https://doi.org/10.1515/corrrev-2022-0065","url":null,"abstract":"Abstract In this study, the resistance of S30432 to low-alkali coal ash corrosion in a high-efficiency USC boiler was investigated. Currently, S30432 is widely used in the high-temperature superheater and reheater of boilers burning low-alkali and high-sulfur coal. During the experiment, S30432 coated with low-alkali coal ash were fixed in a high-temperature tubular reactor, and hot gas at 650 °C and 700 °C containing SO2 passed over the specimens for 2000 h. Then the specimens were tested by X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. It was found that S30432 specimens mainly underwent high-temperature oxidation. For the gas temperature of 700 °C and SO2 volume concentration of 0.35 %, the sulfidation reaction occurred and the weight change was only 1.08 mg cm−2. The results show that there is no obvious high-temperature corrosion after three years of operation of a 700 MW 620 °C boiler. The results are in contrast with the high-alkali coal ash corrosion resistance of S30432. It is concluded that S30432 can meet the requirements of a high-efficiency USC boiler burning low-alkali and high-sulfur coal.","PeriodicalId":10721,"journal":{"name":"Corrosion Reviews","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2023-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48669496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract In order to clarify the influence of different initial texture states on the corrosion mechanism of soluble Mg alloy materials, the as cast and after extruded + perforated (EP) deformed Mg–Gd based soluble magnesium alloys are investigated by the microstructure, surface morphology, surface volta potential, immersion test and electrochemical measurement separately. The results indicate that: the rate of corrosion of the as cast Mg–Gd based soluble magnesium alloy can reach 43.85 mg/cm2/h at 93 °C in a 3 wt% KCl solution, while after EP deformation the rate of corrosion is greatly reduced to only 8.37 mg/cm2/h. Combined with the microstructure analysis, it is concluded that the EP deformed destroyed the coarse reticulated second phase in the as cast structure, which reduced the micro-electrocouple corrosion effect of the second phase. Finally, the corrosion mechanism models for different initial texture states are established through the analysis of microstructure and corrosion morphology, respectively. It is found that the microscopic corrosion mechanism of the as cast Mg–Gd based soluble magnesium alloy is mainly intercrystalline corrosion, which is a superposition of micro-electrocouple corrosion and Mg matrix dissolution. While the microscopic corrosion mechanism of the EP deformed is mainly intracrystalline corrosion, which is manifested as pitting corrosion.
摘要为了阐明不同初始织构状态对可溶性镁合金材料腐蚀机理的影响，分别从微观结构、表面形貌、表面电势、浸渍试验和电化学测试等方面研究了铸态和挤压+穿孔（EP）变形的Mg–Gd基可溶性镁合金。结果表明：铸态Mg–Gd基可溶性镁合金的腐蚀速率可达43.85 mg/cm2/h，93 °C wt%KCl溶液，而EP变形后，腐蚀速率大大降低至仅8.37 mg/cm2/h。结合微观组织分析，认为EP变形破坏了铸态组织中的粗网状第二相，降低了第二相的微电偶腐蚀效应。最后，通过对微观结构和腐蚀形态的分析，分别建立了不同初始织构状态下的腐蚀机理模型。研究发现，铸态Mg–Gd基可溶性镁合金的微观腐蚀机制主要为晶间腐蚀，这是微观电偶腐蚀和镁基体溶解的叠加。而变形EP的微观腐蚀机制主要是晶内腐蚀，表现为点蚀。
{"title":"Study of the corrosion mechanism of Mg–Gd based soluble magnesium alloys with different initial texture states","authors":"Yanchun Zhu, Niulin Wang, Zhibing Chu, Yong-hong Niu, Liang Ma, Ling Qin","doi":"10.1515/corrrev-2023-0035","DOIUrl":"https://doi.org/10.1515/corrrev-2023-0035","url":null,"abstract":"Abstract In order to clarify the influence of different initial texture states on the corrosion mechanism of soluble Mg alloy materials, the as cast and after extruded + perforated (EP) deformed Mg–Gd based soluble magnesium alloys are investigated by the microstructure, surface morphology, surface volta potential, immersion test and electrochemical measurement separately. The results indicate that: the rate of corrosion of the as cast Mg–Gd based soluble magnesium alloy can reach 43.85 mg/cm2/h at 93 °C in a 3 wt% KCl solution, while after EP deformation the rate of corrosion is greatly reduced to only 8.37 mg/cm2/h. Combined with the microstructure analysis, it is concluded that the EP deformed destroyed the coarse reticulated second phase in the as cast structure, which reduced the micro-electrocouple corrosion effect of the second phase. Finally, the corrosion mechanism models for different initial texture states are established through the analysis of microstructure and corrosion morphology, respectively. It is found that the microscopic corrosion mechanism of the as cast Mg–Gd based soluble magnesium alloy is mainly intercrystalline corrosion, which is a superposition of micro-electrocouple corrosion and Mg matrix dissolution. While the microscopic corrosion mechanism of the EP deformed is mainly intracrystalline corrosion, which is manifested as pitting corrosion.","PeriodicalId":10721,"journal":{"name":"Corrosion Reviews","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2023-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44165168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：