Abstract This research paper presents an analysis of the corrosion properties of steel-reinforced concrete samples during immersion in 3.5 wt. % NaCl aqueous solution by measuring their response both cathodic and anodic polarization in order to determine the corrosion rates in the function of their calcium nitrate inhibitor content. This cheap inorganic inhibitor was added to the concrete mix in concentrations of 1% and 3% by weight of cement in addition to two different superplasticizers (MapeiDynamon SR 31 and Oxydtron). The compressive strengths of the so prepared samples were also checked according to the relevant European standard and were within the acceptable limits, so this inhibitor does not weaken this important property of the concrete samples. The test results on steel reinforced samples immersed in 3.5 wt. % NaCl aqueous solutions at room temperature showed promising corrosion mitigating effects just after 6 months testing period. After 6 months the lower corrosion currents (i.e. better corrosion resistance) for both types of superplasticizers were observed with those samples which contained 3% calcium nitrate inhibitor. The best result was observed with sample C4 (in this case 3% calcium nitrate was added to the mixture of cement+Oxydtron superplasticizer). The advantageous inhibition mechanism of nitrate anions is also discussed and interpreted.
摘要本文通过测量钢筋混凝土样品的阴极和阳极极化响应,分析了钢筋混凝土样品在3.5wt.%NaCl水溶液中浸泡期间的腐蚀性能,以确定腐蚀速率与其硝酸钙缓蚀剂含量的函数关系。除了两种不同的超塑化剂(MapeiDynamon SR 31和Oxydtron)之外,还将这种廉价的无机抑制剂以水泥重量的1%和3%的浓度添加到混凝土混合物中。还根据相关欧洲标准检查了如此制备的样品的抗压强度,并且抗压强度在可接受的范围内,因此该抑制剂不会削弱混凝土样品的这一重要性能。在室温下浸泡在3.5wt.%NaCl水溶液中的钢筋样品的测试结果表明,在6个月的测试期后,具有良好的缓蚀效果。6个月后,在含有3%硝酸钙抑制剂的样品中观察到两种类型的超塑化剂的腐蚀电流较低(即耐腐蚀性较好)。用样品C4观察到最佳结果(在这种情况下,将3%的硝酸钙添加到水泥+Oxydtron高效减水剂的混合物中)。并对硝酸根阴离子的有利抑制机理进行了讨论和解释。
{"title":"Corrosion studies on XD3 reinforced concrete samples prepared by using calcium nitrate as inorganic corrosion inhibitor with different superplasticizers","authors":"S. A. Abdulsada, R. Bak, A. Heczel, T. Török","doi":"10.2478/kom-2020-0002","DOIUrl":"https://doi.org/10.2478/kom-2020-0002","url":null,"abstract":"Abstract This research paper presents an analysis of the corrosion properties of steel-reinforced concrete samples during immersion in 3.5 wt. % NaCl aqueous solution by measuring their response both cathodic and anodic polarization in order to determine the corrosion rates in the function of their calcium nitrate inhibitor content. This cheap inorganic inhibitor was added to the concrete mix in concentrations of 1% and 3% by weight of cement in addition to two different superplasticizers (MapeiDynamon SR 31 and Oxydtron). The compressive strengths of the so prepared samples were also checked according to the relevant European standard and were within the acceptable limits, so this inhibitor does not weaken this important property of the concrete samples. The test results on steel reinforced samples immersed in 3.5 wt. % NaCl aqueous solutions at room temperature showed promising corrosion mitigating effects just after 6 months testing period. After 6 months the lower corrosion currents (i.e. better corrosion resistance) for both types of superplasticizers were observed with those samples which contained 3% calcium nitrate inhibitor. The best result was observed with sample C4 (in this case 3% calcium nitrate was added to the mixture of cement+Oxydtron superplasticizer). The advantageous inhibition mechanism of nitrate anions is also discussed and interpreted.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":"64 1","pages":"11 - 18"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46357370","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}
M. Muralimanokar, Vignesh R. Vaira, R. Padmanaban, P. Suganya
Abstract AZ31D magnesium alloy is widely used in automotive, aircraft, and aerospace applications because of its high strength to weight ratio. However, the softness of the alloy results in higher wear rate and the high activity results in higher corrosion rate. With an aim of reducing the wear rate and corrosion rate of AZ31 alloy, surface composite of AZ31 alloy is fabricated by reinforcing niobium carbide (NbC) by friction stir processing. The microstructure and dispersion of the reinforcements in AZ31-NbC surface composite is analysed by optical microscopy. In addition, the microhardness and tribological characteristics of the developed AZ31-NbC surface composite are investigated. The results demonstrated an increase in microhardness (23.2 %) and the decrease in wear rate (15.6 % for a normal load of 2 kg) in the developed AZ31-NbC surface composite with respect to the base material. The immersion corrosion test was performed to analyse the corrosion rate of the developed AZ31-NbC surface composite in simulated sea water environment (3.5 wt % NaCl solution). The results indicate that the corrosion rate of the developed AZ31-NbC surface composite is higher than that of base material. A comprehensive analysis on the wear and corrosion mechanism of the developed AZ31-NbC surface composite is presented.
{"title":"Characterization of AZ31-NbC surface composite fabricated by friction stir processing","authors":"M. Muralimanokar, Vignesh R. Vaira, R. Padmanaban, P. Suganya","doi":"10.2478/kom-2020-0005","DOIUrl":"https://doi.org/10.2478/kom-2020-0005","url":null,"abstract":"Abstract AZ31D magnesium alloy is widely used in automotive, aircraft, and aerospace applications because of its high strength to weight ratio. However, the softness of the alloy results in higher wear rate and the high activity results in higher corrosion rate. With an aim of reducing the wear rate and corrosion rate of AZ31 alloy, surface composite of AZ31 alloy is fabricated by reinforcing niobium carbide (NbC) by friction stir processing. The microstructure and dispersion of the reinforcements in AZ31-NbC surface composite is analysed by optical microscopy. In addition, the microhardness and tribological characteristics of the developed AZ31-NbC surface composite are investigated. The results demonstrated an increase in microhardness (23.2 %) and the decrease in wear rate (15.6 % for a normal load of 2 kg) in the developed AZ31-NbC surface composite with respect to the base material. The immersion corrosion test was performed to analyse the corrosion rate of the developed AZ31-NbC surface composite in simulated sea water environment (3.5 wt % NaCl solution). The results indicate that the corrosion rate of the developed AZ31-NbC surface composite is higher than that of base material. A comprehensive analysis on the wear and corrosion mechanism of the developed AZ31-NbC surface composite is presented.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":"64 1","pages":"29 - 37"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46459658","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}
Králová Z. Orságová, M. Kupková, M. Hrubovčáková, A. Zelenák, R. Oriňaková, Turoňová A. Morovská, K. Žáková, M. Kupka, K. Koval, I. Šišoláková
Abstract The current trend in development of new metallic materials for certain types of implants is turning away from permanent, biologically inert materials to the use of biodegradable materials. Fe–Mn alloys represent high perspective material for development of new generation of temporary and biodegradable implants. The aim of this work was to study mechanical and corrosion characteristics of powder samples containing 25, 30 and 35 wt % of Mn which are fabricated by pressing, sintering, and additional spark plasma sintering. The influence of preparation method (pressing and sintering) to microstructure, phased composition and corrosion behavior of prepared alloys was studied.
{"title":"Mechanical and corrosion properties of iron-mangan materials sintered in the presence of plasma","authors":"Králová Z. Orságová, M. Kupková, M. Hrubovčáková, A. Zelenák, R. Oriňaková, Turoňová A. Morovská, K. Žáková, M. Kupka, K. Koval, I. Šišoláková","doi":"10.2478/kom-2020-0001","DOIUrl":"https://doi.org/10.2478/kom-2020-0001","url":null,"abstract":"Abstract The current trend in development of new metallic materials for certain types of implants is turning away from permanent, biologically inert materials to the use of biodegradable materials. Fe–Mn alloys represent high perspective material for development of new generation of temporary and biodegradable implants. The aim of this work was to study mechanical and corrosion characteristics of powder samples containing 25, 30 and 35 wt % of Mn which are fabricated by pressing, sintering, and additional spark plasma sintering. The influence of preparation method (pressing and sintering) to microstructure, phased composition and corrosion behavior of prepared alloys was studied.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":"64 1","pages":"1 - 10"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49383278","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}
J. Drábiková, S. Fintová, P. Doležal, J. Wasserbauer, Z. Florková
Abstract Magnesium based alloys are very promising material to be used mainly for biodegradable implants in medical applications. However, due to their very low corrosion resistance in the environment of in vivo is their use limited. Increase of the corrosion resistance of magnesium alloys in vivo can be achieved, for example, by a suitable choice of surface treatment while the biocompatibility must be ensured. Fluoride conversion coatings meet these requirements. Unconventional fluoride conversion coating was prepared on ZE41 magnesium alloy by dipping the magnesium alloy into the Na[BF4] salt melt at 450 °C for 0.5; 2 and 8 h. The morphology and thickness of the prepared fluoride conversion coatings were investigated as well as the corrosion resistance of the treated and untreated ZE41 magnesium alloy specimens. The corrosion resistance of the untreated and treated ZE41 magnesium alloy was investigated using electrochemical impedance spectroscopy in the environment of the simulated body fluids at 37 ± 2 °C. The obtained results showed a positive influence of the fluoride conversion coating on the corrosion resistance of the ZE41 magnesium alloy.
{"title":"Corrosion resistance of the biodegradable ZE41 magnesium alloy treated by unconventional fluoride conversion coating","authors":"J. Drábiková, S. Fintová, P. Doležal, J. Wasserbauer, Z. Florková","doi":"10.2478/kom-2019-0018","DOIUrl":"https://doi.org/10.2478/kom-2019-0018","url":null,"abstract":"Abstract Magnesium based alloys are very promising material to be used mainly for biodegradable implants in medical applications. However, due to their very low corrosion resistance in the environment of in vivo is their use limited. Increase of the corrosion resistance of magnesium alloys in vivo can be achieved, for example, by a suitable choice of surface treatment while the biocompatibility must be ensured. Fluoride conversion coatings meet these requirements. Unconventional fluoride conversion coating was prepared on ZE41 magnesium alloy by dipping the magnesium alloy into the Na[BF4] salt melt at 450 °C for 0.5; 2 and 8 h. The morphology and thickness of the prepared fluoride conversion coatings were investigated as well as the corrosion resistance of the treated and untreated ZE41 magnesium alloy specimens. The corrosion resistance of the untreated and treated ZE41 magnesium alloy was investigated using electrochemical impedance spectroscopy in the environment of the simulated body fluids at 37 ± 2 °C. The obtained results showed a positive influence of the fluoride conversion coating on the corrosion resistance of the ZE41 magnesium alloy.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":"63 1","pages":"138 - 147"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41630023","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}
J. Brezinová, A. Guzanová, D. Draganovská, J. Březina
Abstract The paper presents results of the research focused on the characterization of two types of coatings – WC–FeCrAl and WC–WB–Co. The properties of the WC–FeCrAl coating (Co and Ni free) were compared against the WC–WB–Co coating to see if it could be used as an environmentally more suitable substitute for conventional Co and Ni containing powders. The coatings were applied by HVOF technology. The influence of thermal cyclic stress on the hardness, adhesion of coatings and their corrosion resistance was determined. A change in the phase composition of coatings after thermal cyclic loading was also determined.
{"title":"Characterization of selected properties of WC–WB–Co and WC–FeCrAl coatings applied by HVOF technology","authors":"J. Brezinová, A. Guzanová, D. Draganovská, J. Březina","doi":"10.2478/kom-2019-0022","DOIUrl":"https://doi.org/10.2478/kom-2019-0022","url":null,"abstract":"Abstract The paper presents results of the research focused on the characterization of two types of coatings – WC–FeCrAl and WC–WB–Co. The properties of the WC–FeCrAl coating (Co and Ni free) were compared against the WC–WB–Co coating to see if it could be used as an environmentally more suitable substitute for conventional Co and Ni containing powders. The coatings were applied by HVOF technology. The influence of thermal cyclic stress on the hardness, adhesion of coatings and their corrosion resistance was determined. A change in the phase composition of coatings after thermal cyclic loading was also determined.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":"63 1","pages":"167 - 173"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45033802","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}
J. Tkáčová, E. Zdravecká, E. Evin, M. Tomáš, D. Jakubéczyová
Abstract For achieving a long service life of stamping dies for new types of steel sheets intended for the automotive industry, the tribosystem must be optimally designed. One of the possible solutions is its optimization by coatings. More modern coating technologies for stamping dies include PVD (physical vapor deposition) and CVD (chemical vapor deposition) methods. The properties of PVD TiCN and DLC (diamond-like carbon) coatings deposited on ledeburitic high-alloy Cr–Mo–V steel were analyzed by standard tests (coating adhesion by both the scratch and Rockwell C tests, microhardness by Vickers method and coating thickness by Calotest) and developed tribo-meter of the “friction jaw-roller” type at drawing double-sided hot-dip galvanized steel sheet. The obtained results showed better tribological behavior of the DLC coating.
{"title":"Evaluation of selected properties of coatings in respect of risk elimination of surface damage of stamped parts","authors":"J. Tkáčová, E. Zdravecká, E. Evin, M. Tomáš, D. Jakubéczyová","doi":"10.2478/kom-2019-0021","DOIUrl":"https://doi.org/10.2478/kom-2019-0021","url":null,"abstract":"Abstract For achieving a long service life of stamping dies for new types of steel sheets intended for the automotive industry, the tribosystem must be optimally designed. One of the possible solutions is its optimization by coatings. More modern coating technologies for stamping dies include PVD (physical vapor deposition) and CVD (chemical vapor deposition) methods. The properties of PVD TiCN and DLC (diamond-like carbon) coatings deposited on ledeburitic high-alloy Cr–Mo–V steel were analyzed by standard tests (coating adhesion by both the scratch and Rockwell C tests, microhardness by Vickers method and coating thickness by Calotest) and developed tribo-meter of the “friction jaw-roller” type at drawing double-sided hot-dip galvanized steel sheet. The obtained results showed better tribological behavior of the DLC coating.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":"63 1","pages":"159 - 166"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47371885","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}
Abstract Corrosion flaws in pipelines can caused severe financial losses and also can be dangerous for people. One of the most frequently damaged parts are dissimilar pipe welds. We would like to understand how corrosion process reacts on corrosion product removal. Outputs from experiment will be used for production of test specimens. For testing we chose standard dissimilar weldment used in Czech power plants. It is joint with 08Ch18N10T and 22K (GOST) steel. Joint is cut to 24 same specimens. There are exposed to flowing water solution of 5% NaCl. Half of the specimens are regularly mechanically cleaned. The joint is metallographically observed and parts with and without corrosion products are compared. Water salt solution increased pH from 7,25 to 7,86 during 31 days test and conductivity varies around 74 mS cm−1. Metallographic observation indicates that corrosion under corrosion products layer is locally speed up and causes pitting corrosion. Cleaned specimens indicate plane corrosion with lower depth. These results indicate that slag in pipeline could locally speed up corrosion depth penetration. On the other hand, solutions with abrasive particles (which can wipe out the corrosion product) will probably facilitate plane corrosion damage on pipeline walls. This test brings us another knowledge, how to simulate realistic corrosion damage for production of NDT qualification test pieces.
摘要管道的腐蚀缺陷不仅会造成严重的经济损失,而且会危及人身安全。最常损坏的部件之一是不同的管道焊缝。我们想了解腐蚀过程对腐蚀产物去除的反应。实验结果将用于制作测试样品。试验选用捷克电厂标准异种焊件。它与08Ch18N10T和22K (GOST)钢接合。关节被切割成24个相同的标本。暴露于5% NaCl的流动水溶液中。一半的标本定期进行机械清洗。对接头进行金相观察,并对有腐蚀产物和无腐蚀产物的零件进行比较。在31天的测试中,水盐溶液的pH值从7.25增加到7.86,电导率在74 mS cm−1左右变化。金相观察表明,腐蚀产物层下的腐蚀局部加速,产生点蚀。清洗后的试样显示深度较低的平面腐蚀。研究结果表明,管道中的炉渣可以局部加速腐蚀深度渗透。另一方面,含有磨料颗粒的溶液(可以擦除腐蚀产物)可能会促进管道壁面的腐蚀破坏。该试验为我们提供了另一种知识,即如何模拟真实的腐蚀损伤,为生产无损检测合格试件提供依据。
{"title":"Impact of corrosion product removal to depth of corrosion damage in weldment joint","authors":"J. Hodač, Z. Fulin","doi":"10.2478/kom-2019-0019","DOIUrl":"https://doi.org/10.2478/kom-2019-0019","url":null,"abstract":"Abstract Corrosion flaws in pipelines can caused severe financial losses and also can be dangerous for people. One of the most frequently damaged parts are dissimilar pipe welds. We would like to understand how corrosion process reacts on corrosion product removal. Outputs from experiment will be used for production of test specimens. For testing we chose standard dissimilar weldment used in Czech power plants. It is joint with 08Ch18N10T and 22K (GOST) steel. Joint is cut to 24 same specimens. There are exposed to flowing water solution of 5% NaCl. Half of the specimens are regularly mechanically cleaned. The joint is metallographically observed and parts with and without corrosion products are compared. Water salt solution increased pH from 7,25 to 7,86 during 31 days test and conductivity varies around 74 mS cm−1. Metallographic observation indicates that corrosion under corrosion products layer is locally speed up and causes pitting corrosion. Cleaned specimens indicate plane corrosion with lower depth. These results indicate that slag in pipeline could locally speed up corrosion depth penetration. On the other hand, solutions with abrasive particles (which can wipe out the corrosion product) will probably facilitate plane corrosion damage on pipeline walls. This test brings us another knowledge, how to simulate realistic corrosion damage for production of NDT qualification test pieces.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":"63 1","pages":"148 - 152"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46524415","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}
D. Steinerová, A. Kalendová, J. Machotová, M. Kohl
Abstract Water based paints are increasingly attracting interest mainly with a view to reducing air pollution with volatile organic compounds (VOC). However, the protective properties of water-based paints are inferior to those of solvent-based paints and so new ways to increase the resistance of water-based systems are sought. The present contribution describes the preparation and testing of environmentally friendly anti-corrosion paints based on novel water-based self-crosslinking acrylate latexes containing appropriate pigments and ZnO or MgO nanoparticles at a concentration of 1.5 % (with respect to the monomers) compared to the same systems free from the nanoparticles. Both the effect of the MeO nanoparticles and the effects of the pigment species and particle shapes on the paint film properties were examined. The MeO nanoparticles were found to improve all the properties tested. The latexes with MgO exhibited the highest resistance to flash corrosion while the latexes with ZnO exhibited the highest anticorrosion resistance. Furthermore, the systems with the calcium-aluminium polyphosphosilicate based pigment were superior to all the remaining systems in this respect. It is concluded that binders with nanoparticles can be used as a basis for anticorrosion coatings provided that a suitable pigment is selected.
{"title":"Anticorrosion coatings based on novel acrylate binders containing MeO nanoparticles","authors":"D. Steinerová, A. Kalendová, J. Machotová, M. Kohl","doi":"10.2478/kom-2019-0020","DOIUrl":"https://doi.org/10.2478/kom-2019-0020","url":null,"abstract":"Abstract Water based paints are increasingly attracting interest mainly with a view to reducing air pollution with volatile organic compounds (VOC). However, the protective properties of water-based paints are inferior to those of solvent-based paints and so new ways to increase the resistance of water-based systems are sought. The present contribution describes the preparation and testing of environmentally friendly anti-corrosion paints based on novel water-based self-crosslinking acrylate latexes containing appropriate pigments and ZnO or MgO nanoparticles at a concentration of 1.5 % (with respect to the monomers) compared to the same systems free from the nanoparticles. Both the effect of the MeO nanoparticles and the effects of the pigment species and particle shapes on the paint film properties were examined. The MeO nanoparticles were found to improve all the properties tested. The latexes with MgO exhibited the highest resistance to flash corrosion while the latexes with ZnO exhibited the highest anticorrosion resistance. Furthermore, the systems with the calcium-aluminium polyphosphosilicate based pigment were superior to all the remaining systems in this respect. It is concluded that binders with nanoparticles can be used as a basis for anticorrosion coatings provided that a suitable pigment is selected.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":"63 1","pages":"153 - 158"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69228456","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}
Abstract Ethanol produced from renewable resources is considered as an ecological substitute for a fossil gasoline. Ethanol blended with the fossil gasoline is able to significantly change the properties of the blended fuel as polarity, conductivity, ability to absorb air humidity and ability to dissolve a high percentage of water etc. All these properties are growing with an increasing content of ethanol and all of them can cause higher corrosivity of blended fuel. Material compatibility of metalic construction materials of the vehicle fuel system is also decreased in the environment of ethanol – gasoline blends (EGB’s). Furthermore, components of production, transport and storage equipment may be at risk of corrosion. EGB’s with an ethanol content of about 60% vol. show high corrosive aggressivness, especially if they are contaminated with water and trace amounts of ion, which may occur if proper storage, transport and production conditions are violated. Losses caused by corrosion of equipment may be prevented by using of suitable additive. Diethylenetriamine (DETA) can be used as such additive for the mild steel which is one of the most commonly used construction material. When DETA is used, it shows very high efficiency.
{"title":"Corrosion and corrosion inhibition in an environment of ethanol – gasoline blends","authors":"L. Matějovský, O. Pleyer, J. Macák","doi":"10.2478/kom-2019-0016","DOIUrl":"https://doi.org/10.2478/kom-2019-0016","url":null,"abstract":"Abstract Ethanol produced from renewable resources is considered as an ecological substitute for a fossil gasoline. Ethanol blended with the fossil gasoline is able to significantly change the properties of the blended fuel as polarity, conductivity, ability to absorb air humidity and ability to dissolve a high percentage of water etc. All these properties are growing with an increasing content of ethanol and all of them can cause higher corrosivity of blended fuel. Material compatibility of metalic construction materials of the vehicle fuel system is also decreased in the environment of ethanol – gasoline blends (EGB’s). Furthermore, components of production, transport and storage equipment may be at risk of corrosion. EGB’s with an ethanol content of about 60% vol. show high corrosive aggressivness, especially if they are contaminated with water and trace amounts of ion, which may occur if proper storage, transport and production conditions are violated. Losses caused by corrosion of equipment may be prevented by using of suitable additive. Diethylenetriamine (DETA) can be used as such additive for the mild steel which is one of the most commonly used construction material. When DETA is used, it shows very high efficiency.","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":"63 1","pages":"121 - 129"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49221083","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. Poberezhny, A. Stanetsky, G. Grytsuliak, L. Poberezhna, M. Kosmii, A. Hrytsanchuk
Abstract The study of the deformation behavior of the pipeline material in conditions of loads and influences simulating the operation allows better estimation of the residual life of the pipelines and more accurate forecasting of the operating costs. The kinetics of deformation in 6 model environments simulating soil electrolytes was studied. Corrosion-mechanical tests were performed and the impact of the soil electrolyte chemical composition and the applied mechanical stresses on the corrosion behavior of the pipeline steel was studied. Significant increase in the corrosion activity of the soil electrolyte due to the synergistic effect of the corrosion-active components was found in the specified ratios of the ionic molar concentrations of sulphate and chloride ions (0.05 M: 0.1 M).
{"title":"Corrosion-mechanical behavior of gas main steel in saline soils","authors":"L. Poberezhny, A. Stanetsky, G. Grytsuliak, L. Poberezhna, M. Kosmii, A. Hrytsanchuk","doi":"10.2478/kom-2019-0014","DOIUrl":"https://doi.org/10.2478/kom-2019-0014","url":null,"abstract":"Abstract The study of the deformation behavior of the pipeline material in conditions of loads and influences simulating the operation allows better estimation of the residual life of the pipelines and more accurate forecasting of the operating costs. The kinetics of deformation in 6 model environments simulating soil electrolytes was studied. Corrosion-mechanical tests were performed and the impact of the soil electrolyte chemical composition and the applied mechanical stresses on the corrosion behavior of the pipeline steel was studied. Significant increase in the corrosion activity of the soil electrolyte due to the synergistic effect of the corrosion-active components was found in the specified ratios of the ionic molar concentrations of sulphate and chloride ions (0.05 M: 0.1 M).","PeriodicalId":17911,"journal":{"name":"Koroze a ochrana materialu","volume":"63 1","pages":"105 - 112"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43405218","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}