{"title":"Electrochemical mechanism of metall corrosion","authors":"","doi":"10.31615/j.corros.prot.2021.99.1-4","DOIUrl":"https://doi.org/10.31615/j.corros.prot.2021.99.1-4","url":null,"abstract":"Corrosion that occurs by an electrochemical mechanism is a combination of cathodic and anodic reactions that occur independently of each other. At that, the metal surface is considered to be equipotential one, i.e. the presence of short-circuited microgalvanic pairs on the surface is not a necessary condition for electrochemical corrosion. The anode and cathode processes are spatially separated. This is provided by the presence of conduction electrons in the interstitial spaces of the metal lattice. The present model of electrochemical corrosion justifies the use of polarization diagrams for the analysis of corrosion processes. The previously proposed model, based on the idea that a necessary condition for electrochemical corrosion is the presence of short-circuited microgalvanic elements on the metal surface, is erroneous. When considering electrochemical corrosion from the positions of this model, the use of polarization diagrams to study corrosion processes is not legitimate.","PeriodicalId":20323,"journal":{"name":"Practice of Anticorrosive Protection","volume":"68 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90774760","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}
{"title":"Electroplating of iron and its alloys","authors":"","doi":"10.31615/j.corros.prot.2021.99.1-5","DOIUrl":"https://doi.org/10.31615/j.corros.prot.2021.99.1-5","url":null,"abstract":"Analytical review of information on electrodeposition of iron and its alloys from aqueous solutions is carried out. Processes of electroplating of iron and its alloys from aqueous solutions and the principal fields of application of these galvanic coatings are discussed. The principal technological advantages of using iron coatings in the reconditioning of steel parts are considered. Compositions of electrolytes and conditions for plating of iron coatings are provided. Technological parameters of electroplating of iron from industrial electrolytes are considered. Data are presented on the effect of some organic additives on the iron plating process. The effect of the concentration of Fe3+ ions in iron plating electrolytes on electroplating of iron coatings and their physic-mechanical properties is discussed. The data are presented on physic-mechanical properties of iron coatings obtained in different electrolysis modes. Nonsteady-state electrolysis modes are discussed that are used in industry for application of iron coatings. The effect of coating plating conditions on their mechanical properties is studied. Technological parameters of electroplating of iron alloys are considered. Co-deposition of iron with nickel, chromium, titanium, phosphorus, molybdenum, vanadium and tungsten is described. Data are provided on compositions of electrolytes and conditions of electroplating of these alloys. Main fields of application of electroplated iron alloys are discussed. Information is provided.","PeriodicalId":20323,"journal":{"name":"Practice of Anticorrosive Protection","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83560496","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}
{"title":"Results of paint coating full-scale tests for coastal and ship structures in the tropical climate of Vietnam","authors":"","doi":"10.31615/j.corros.prot.2021.99.1-2","DOIUrl":"https://doi.org/10.31615/j.corros.prot.2021.99.1-2","url":null,"abstract":"Full-scale tests are widely used to reliably evaluation the service life of paint and varnish coatings by assessing changes of their protective and decorative properties. Four-year exposure program was carried out in the tropical marine climate in South Vietnam (Dam Bay climate station of the Tre island, Nha Trang) of alkyd, chlorinated rubber coatings on low carbon steel, as well as epoxy coatings of various thicknesses with zinc-rich primer, urethane and acrylic outer layers. The tests were conducted on the base of the existing standards in the field of paints and varnishes intended for coastal and ship structures and were accompanied by the data collection and analysis of the meteorological factors for the classification of the area according to the degree of corrosiveness of the atmosphere. The change in the decorative properties of paint coating was assessed by visual and instrumental methods. The protective efficiency of the coatings was assessed by the time of occurrence of the first local defects or complete destruction of coating layers. According to the results of the conducted field tests, it was found that paint coating combinations correspond to expected lifetime in tropical climate from 2 to 5 years. A typical group suitable for a given climate is a two-component epoxy paint with an acrylic topcoat. A zinc-containing primer is recommended as an anticorrosive undercoat.","PeriodicalId":20323,"journal":{"name":"Practice of Anticorrosive Protection","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72791076","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}
{"title":"The study of the effectiveness of corrosion protection of zinc-rich coating on the base of water sodium silicate","authors":"","doi":"10.31615/j.corros.prot.2020.98.4-4","DOIUrl":"https://doi.org/10.31615/j.corros.prot.2020.98.4-4","url":null,"abstract":"The study is examines the assessment of the corrosion-protective properties of zinc-rich coating based on water sodium silicate (ZRC) using the Electrochemical Impedance Spectra (EIS) with AutoLAB PGSTAT204N. The system consists of three electrodes: Ag/AgCl reference electrode in 3 M solution of KCl, auxiliary electrode – Pt (8x8 mm) and working electrodes for determination potential (Ecorr) and impedance measurement, salt spray test method and natural teszzt method at Dam Bay Marine Research Station, Nha Trang, Khanh Hoa, Viet Nam. ZSC can provide good cathodic protection when zinc content is 70% by weight or more. ZSC with a mixing ratio of High Modulus Liquid Sodium Glass / Zinc Powde : 25/75 by weight (working title – TTL-VN) has good corrosion protection after 16 cycles salt spray test and after 18 months natural test in seawater. The paint film has basic parameters as adhesion – 4,41 MPa, flexural strength – 2 mm, pendulum hardness – 0,62 conventional units and initial coating potentia l – 0,96 V Ag/AgCl.","PeriodicalId":20323,"journal":{"name":"Practice of Anticorrosive Protection","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89457483","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}
{"title":"Influence of oligomethylenaryl sulphonates based on the light gas oil of catalytic cracking on the process of biocorrosion","authors":"","doi":"10.31615/j.corros.prot.2020.98.4-2","DOIUrl":"https://doi.org/10.31615/j.corros.prot.2020.98.4-2","url":null,"abstract":"This article presents the results of studies in the field of synthesis of water-soluble salts of oligomethylene aryl sulfonates synthesized using aromatic hydrocarbons contained in the gas oil fraction of the catalytic cracking process of oil as raw materials. Based on the synthesized various salts of oligoaromatic sulfonic acids (sodium, potassium, ammonium salts), solutions of various concentrations (35; 75; 150; 200 mg/l) were prepared and their effect on the vital activity of sulfate-reducing bacteria at a temperature of 30…32 °С for 7…14 days was studied. It was found that complex salts synthesized on the basis of oligomeric sulfonic acids of aromatic hydrocarbons of the gas oil fraction (N-1, N-2, N-3) at a concentration of 150 mg/l exhibit more than 90%, and at a concentration of 200 mg/l, 100% bactericidal effect and completely inhibits the growth of bacteria. It was revealed that the synthesized salts of sulfonic acids exhibit a relatively higher antimicrobial activity against SRB than the industrial bactericidal inhibitors AMDOR-IK-7 and AMDOR-IK-10 taken as a reference. Based on the studies, it was found that the synthesized salts of oligosulfonic acids completely inhibit the growth of sulfate-reducing bacteria at much lower concentrations compared to the industrially used bactericidal inhibitors taken as a reference. In particular, at a concentration of 150 mg/l, the bactericidal effect is more than 90% against 75…80% for the standard.","PeriodicalId":20323,"journal":{"name":"Practice of Anticorrosive Protection","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81297624","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}
{"title":"Inhibition of Corrosion of structural steels (St3)","authors":"","doi":"10.31615/j.corros.prot.2020.98.4-5","DOIUrl":"https://doi.org/10.31615/j.corros.prot.2020.98.4-5","url":null,"abstract":"Compositions based on hydroxyethylidene diphosphonic and nitrilotrimethylenephosphonic acids with alkali earth metals (Ca, Mg) are studied as corrosion inhibitors. It is found that the studied compositions are not inferior to their zinc counterparts as regards their corrosion inhibition efficiency and can be used in two-circuit cooling systems.","PeriodicalId":20323,"journal":{"name":"Practice of Anticorrosive Protection","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79669296","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}
{"title":"Selection of an inhibitor for corrosion protection of the inter-pipe space of the underwater transition of the “Pavlodar – Shymkent” oil pipeline through the Irtysh river","authors":"","doi":"10.31615/j.corros.prot.2020.98.4-3","DOIUrl":"https://doi.org/10.31615/j.corros.prot.2020.98.4-3","url":null,"abstract":"The article presents a study of the protection degree of a model inhibiting solution samples in order to select the optimal inhibitor for protecting the annular space of the underwater crossing of the “Pavlodar-Shymkent” main oil pipeline across the Irtysh river built by the pipe-in-pipe method. In order to determine the corrosion rate of pipe steel we used witness coupons made of 17G1S steel similar to the steel of the pipeline in operation. Gravimetric and electrochemical methods were used to study the inhibitory properties of inhibiting solutions consisting of corrosion inhibitors Rancor 1101, CRW 82590, VpCI 337, ForeRP 40, and water from the Irtysh river. We carried out comparative analysis of the corrosion rates of pipe steel and the protection degree of inhibitor solutions at various concentrations. Any of inhibitors in concentrations from 50 to 750 ppm, in static mode, do not provide a protective effect, at which steel 17G1S shows increased resistance in a corrosive environment of water samples from the river Irtysh (reduction of the average corrosion rate to 0.005 mm/year according to GOST). Comparing the protective ability of corrosion inhibitors in a corrosive environment from water samples from r. Irtysh, it has been exhibited that the Baker Hughes inhibitor CRW 82590 shows the best protective ability, in static mode during gravimetric studies 80,38% (500 ppm) and 82,52% (750 ppm), in static mode during electrochemical studies 85,90% (500 and 750 ppm).","PeriodicalId":20323,"journal":{"name":"Practice of Anticorrosive Protection","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81221585","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}
{"title":"Aggressive environmental factors causing corrosion at gas production facilities in the presence of carbon dioxide","authors":"","doi":"10.31615/j.corros.prot.2020.98.4-1","DOIUrl":"https://doi.org/10.31615/j.corros.prot.2020.98.4-1","url":null,"abstract":"The current stage in the development of promising gas and gas condensate fields in the Russian Federation is associated with facilities whose production includes carbon dioxide. Such objects include the Urengoyskoye oil and gas condensate field (Achimov deposits), the Bovanenkovskoye oil and gas condensate field, and the Kirinskoye gas and condensate field. The presence of CO2 in the produced gas, in combination with moisture condensation and a number of other factors, stimulates the intensive development of local corrosion processes. The main factors that influence the development of corrosion at infrastructure facilities and its localization in the presence of CO2 are considered. It is noted that when assessing the degree of aggressiveness of the environment, it is necessary to consider not only the CO2 content, but also other basic operating parameters that can affect corrosion. During the exploitation of gas fields, the conditions of moisture condensation that contribute to corrosion arise, which occurs when a temperature gradient arises and the produced gas is rapidly cooled. Higher temperatures increase both the amount of precipitated moisture and, accordingly, the rate of local corrosion. Simulation tests have shown that the development of local forms of corrosion (pitting, ulcers) are possible even at low CO2 partial pressures (from 0,025 MPa and above) in the presence of condensed moisture.","PeriodicalId":20323,"journal":{"name":"Practice of Anticorrosive Protection","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80658906","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}
{"title":"Effect of leucine on the activation energy of the corrosion process of St3 steel in 0,04% CH3COOH solution – kerosene system","authors":"","doi":"10.31615/j.corros.prot.2020.98.4-6","DOIUrl":"https://doi.org/10.31615/j.corros.prot.2020.98.4-6","url":null,"abstract":"In this investigation we studied the temperature dependence of the protection effect of St3 steel against corrosion in 0,04% CH3COOH solution-kerosene system by gravimetric method of leucine (derivative of aliphatic monoamino monocarboxylic acids – AL-MAMCA: with the general formula CH3-CH(CH3)-CH2-CH(NH2)-COOH). Previously at 20 ºC we investigated this corrosion process in various two-phase acid and neutral electrolyte solutions in hydrocarbon systems and revealed a good protection effect of leucine. On the basis of the obtained data, the activation energy in the corrosion process of St3 steel has been calculated without and in the presence of the leucine in the aggressive system shown by analytical and graphical methods (graph of dependence of lgK on 1/T). It was found that the addition of leucine to the aggressive system in terms of corrosion causes a significant increase in the activation energy of St3 steel in the corrosion process, and thus complicates the process of this undesirable process. It has been shown that in parallel with the increase in the temperature of the aggressive environment in terms of corrosion, the previously physically adsorbed leucine molecules on the surface of St3 steel are gradually replaced by chemically adsorbed ones, thus further strengthening the metal – inhibitor bond.","PeriodicalId":20323,"journal":{"name":"Practice of Anticorrosive Protection","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73360276","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}
{"title":"Electrochemical study of carbon steel protection with a superhydrophobic coating under conditions of 100% humidity and the presence of corrosion stimulants in the air","authors":"","doi":"10.31615/j.corros.prot.2020.97.3-2","DOIUrl":"https://doi.org/10.31615/j.corros.prot.2020.97.3-2","url":null,"abstract":"100% humidity and the presence in the air of such corrosion stimulants as CO2, NH3 and H2S are characteristic of livestock buildings. Under these conditions, a surface phase film of moisture is formed on the surface of the metals in which the indicated micro-mixtures of air are dissolved and hydrated almost completely with the formation of NH4OH and acids H2CO3 and H2S. The potentiodynamic polarization method was used to study the corrosion and kinetics of electrode processes on steel with a superhydrophobic coating in a NaCl background solution (used to provide sufficient electrical conductivity) saturated in pairs with CO2 and NH3, NH3 and H2S. Similar studies were conducted with uncoated electrodes. Superhydrophobic coating was obtained on the basis of laser texturing of the surface with subsequent hydrophobization with fluoroxysilane (wetting angle 165±2°, rolling angle 3±1°). The influence of the duration of the exposure of the electrodes in solution (0,25…168 h) on the kinetics of electrode processes and the corrosion rate of steel is considered. In the presence of CO2 and NH3 dissolution products, the corrosion rate of an electrode with a superhydrophobic coating on the second and third days of exposure is about an order of magnitude, and on the fourth and seventh days it is more than an order of magnitude lower than without coating. During the entire time the electrodes are in solution, the anode process on the superhydrophobic electrode is inhibited compared to an unprotected electrode. The medium containing the dissolution products of NH3 and H2S is more aggressive than the previous solution. Therefore, the corrosion rate of the electrodes without coating and with a coating here is higher than in the latter one. The corrosion rate of electrodes with superhydrophobic coating in the study period is only 1,5…2,5 times lower than that of uncoated electrodes. During the first day of exposure, the anode process is inhibited, and in the next 144 hours, on the contrary, it is facilitated in comparison with an unprotected electrode. Taking into account the corrosivity of the chloride solution, the possible effect of the dissolution products of aggressive air micro-impurities in the absence of background salt was analyzed.","PeriodicalId":20323,"journal":{"name":"Practice of Anticorrosive Protection","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90975192","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}