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Sample records for steel corrosion protection

  1. Protection of Steel Constructions from Corrosive Destruction

    International Science & Technology Center (ISTC)

    Development of the New Effective Sacrificial Anodes on the Basis of Secondary Aluminum for Protection of Steel Constructions of Hydropower Stations and Heat Stations of the Republic of Tajikistan from Corrosion Destruction

  2. AC corrosion on cathodically protected steel

    OpenAIRE

    Torstensen, Andreas

    2012-01-01

    This report deals with the effect of alternating current on cathodically protected steel. AC corrosion has become relevant in the offshore industry due to the introduction of the direct electric heating system (DEH). The principle with DEH is to prevent wax solidification inside pipelines by heating them up with alternating current. This can give rise to AC corrosion.DC current densities, AC current densities and DC potential have been measured for steel samples under cathodic protection with...

  3. Guidelines for the Protection of Steel Piles : Corrosive Marine Environment

    OpenAIRE

    Rhodes, Graham

    2011-01-01

    The corrosion of steel is a common phenomenon. In a marine environment, steel is corroded at an accelerated rate due to the atmospheric conditions. To combat this corrosion, steel piles are coated in order to protect them. As a major supplier of steel piles, Rautaruukki Oyj (Ruukki) commissioned this project in order to streamline their coating process. Currently Ruukki supplies a different coating system for almost every job; the aim of the project was to reduce the number of systems used to...

  4. Electric corrosion protection method for steel material

    International Nuclear Information System (INIS)

    A semiconductor having a thermoelectric performance of 920?V/K or more is incorporated between a steel material of a light water reactor to be in contact with high temperature water and an aqueous solution. This shifts the corrosion potential of the steel material in a high temperature water to more basic side. Satisfactory corrosion resistant metal silicate, for example, FeSi2 is preferably used for the thermoelectric semiconductor. Co is added to FeSi2 to form an n-type semiconductor. A layer of Si3N4 is formed to the circumference of a cylindrical FeSi2 to form an insulation layer. This member is disposed to a hole bored to a stainless steel pipe, and the one surface is brought into contact with high temperature water on the inner side of the stainless steel. On the other side in contact with the outer atmosphere is bonded to the outer surface of the stainless steel pipe by a lead wire. Since the n-type semiconductor has a positive potential on the side at a higher temperature, the potential of the stainless steel is determined to negative. (I.N.)

  5. Corrosion protection

    Science.gov (United States)

    Brown, Donald W.; Wagh, Arun S.

    2003-05-27

    There has been invented a chemically bonded phosphate corrosion protection material and process for application of the corrosion protection material for corrosion prevention. A slurry of iron oxide and phosphoric acid is used to contact a warm surface of iron, steel or other metal to be treated. In the presence of ferrous ions from the iron, steel or other metal, the slurry reacts to form iron phosphates which form grains chemically bonded onto the surface of the steel.

  6. Investigation of Corrosion and Cathodic Protection in Reinforced Concrete. II: Properties of Steel Surface Layers:

    OpenAIRE

    Koleva, D. A.; Wit, J.H.W. de; Breugel, K., van; Lodhi, Z.F.; Ye, G.

    2007-01-01

    The present study explores the formation of corrosion products on the steel surface (using as-received low carbon construction steel) in reinforced concrete in conditions of corrosion and subsequent transformation of these layers in conditions of cathodic protection (CP).

  7. Spectroscopic identification of protective and non-protective corrosion coatings on steel structures in marine environments

    Energy Technology Data Exchange (ETDEWEB)

    Cook, Desmond C. [Department of Physics, Old Dominion University, Norfolk, VA 23529 (United States)]. E-mail: dcook@physics.odu.edu

    2005-10-01

    Corrosion research, and the need to fully understand the effects that environmental conditions have on the performance of structural steels, is one area in which Moessbauer spectroscopy has become a required analytical technique. This is in part due to the need to identify and quantify the nanophase iron oxides that form on and protect certain structural steels, and that are nearly transparent to most other spectroscopic techniques. In conjunction with X-ray diffraction and micro-Raman analyses, the iron oxides that form the rusts on steels corroded in different marine and other environments can be completely identified and mapped within the rust coating. The spectroscopic analyses can be used to determine the nature of the environment in which structural steels have been, and these act as a monitor of the corrosion itself. Moessbauer spectroscopy is playing an important role in a new corrosion program in the United States and Japan in which steel bridges, old and new, are being evaluated for corrosion problems that may reduce their serviceable lifetimes. Moessbauer spectroscopy has been used to characterize the corrosion products that form the protective patina on weathering steel, as well those that form in adverse environments in which the oxide coating is not adherent or protective to the steel. Moessbauer spectroscopy has also become an important analytical technique for investigating the corrosion products that have formed on archaeological artifacts, and it is providing guidance to aid in the removal of the oxides necessary for their conservation.

  8. Spectroscopic identification of protective and non-protective corrosion coatings on steel structures in marine environments

    International Nuclear Information System (INIS)

    Corrosion research, and the need to fully understand the effects that environmental conditions have on the performance of structural steels, is one area in which Moessbauer spectroscopy has become a required analytical technique. This is in part due to the need to identify and quantify the nanophase iron oxides that form on and protect certain structural steels, and that are nearly transparent to most other spectroscopic techniques. In conjunction with X-ray diffraction and micro-Raman analyses, the iron oxides that form the rusts on steels corroded in different marine and other environments can be completely identified and mapped within the rust coating. The spectroscopic analyses can be used to determine the nature of the environment in which structural steels have been, and these act as a monitor of the corrosion itself. Moessbauer spectroscopy is playing an important role in a new corrosion program in the United States and Japan in which steel bridges, old and new, are being evaluated for corrosion problems that may reduce their serviceable lifetimes. Moessbauer spectroscopy has been used to characterize the corrosion products that form the protective patina on weathering steel, as well those that form in adverse environments in which the oxide coating is not adherent or protective to the steel. Moessbauer spectroscopy has also become an important analytical technique for investigating the corrosion products that have formed on archaeological artifacts, and it is providing guidance to aid in the removal of the oxides necessary for their conservation

  9. Bilayers Polypyrrole Coatings for Corrosion Protection of SAE 4140 Steel

    Scientific Electronic Library Online (English)

    I.L., Lehr; S.B., Saidman.

    2014-07-01

    Full Text Available In this study polypyrrole (PPy) bilayers films were electrodeposited onto SAE 4140 steel. The inner layer was electropolymerized in the presence of molibdate and nitrate and the outer layer in a solution containing sodium bis (2-ethylhexyl) sulfosuccinate (AOT). The electrosynthesis was done under p [...] otentiostatic conditions. The corrosion protection properties of the films were examined in sodium chloride solution by open circuit measurements, linear polarization and electrochemical impedance spectroscopy (EIS). The bilayer coatings present an improved anticorrosive performance with respect to single PPy films.

  10. Corrosion protection of steel in ammonia/water heat pumps

    Science.gov (United States)

    Mansfeld, Florian B.; Sun, Zhaoli

    2003-10-14

    Corrosion of steel surfaces in a heat pump is inhibited by adding a rare earth metal salt to the heat pump's ammonia/water working fluid. In preferred embodiments, the rare earth metal salt includes cerium, and the steel surfaces are cerated to enhance the corrosion-inhibiting effects.

  11. Corrosion protection mechanism of polyaniline blended organic coating on steel

    Energy Technology Data Exchange (ETDEWEB)

    Sathiyanarayanan, S.; Jeyaram, R.; Muthukrishnan, S.; Venkatachari, G. [Central Electrochemical Research Institute, Karaikkudi (India)

    2009-07-01

    Epoxy-coal tar coatings are widely used to protect steel structures exposed to marine atmosphere due to their good barrier property. However, the presence of micropores and microcracks formed during the coating formation leads to failure of the coating due to permeation of corrosive ions. In recent years, it has been established that the coatings containing polyaniline (PANI) is able to protect pinholes and defects due to its passivating ability. Hence, a study has been made on the effect of polyaniline content (1 and 3%) in epoxy-coal tar coating on the corrosion protection of steel in 3% NaCl solution by electrochemical impedance spectroscopy (EIS) studies. Both phosphate- and chloride-doped polyanilines were prepared by a chemical oxidative polymerization method. From EIS studies, it has been found that the resistance value of the coatings containing 1 and 3% phosphate-doped polyaniline and 3% chloride-doped polyaniline pigmented coatings are similar to 10{sup 9} {Omega} cm{sup 2} even after 90 days exposure to NaCl solution, which are two orders high in comparison to that of conventional coal tar epoxy coatings. Besides, the conducting state of polyaniline has been found to be decreased after exposure to NaCl solution due to redox property of PANI. X-ray photoelectron spectroscopy studies have shown that polyaniline forms a complex layer with iron beneath the coating along with iron oxide.

  12. Corrosion Protection of Hot Dip Galvanized Steel in Mortar

    Scientific Electronic Library Online (English)

    Rita M., Figueira; Elsa V., Pereira; Carlos J.R., Silva; Maria M., Salta.

    2013-10-08

    Full Text Available Corrosion of steel in concrete is one of the major causes of structure degradation, requiring expensive maintenance. The using of hot dip galvanized steel (HDGS) has been recognized as one effective measure to increase the service life of reinforced concrete structures in marine environmental. Howev [...] er, HDGS corrodes in contact with high alkaline environment of fresh concrete. Although this initial corrosion process allows the formation of a protecting layer barrier, the corrosion that occurs initially is harmful and chromate conversion layers are usually used to prevent it. Due to toxicity of Cr(VI), these kinds of pre-treatments have been forbidden and hybrid coatings have been proposed as alternatives [1-3]. To evaluate the performance of these coatings, beyond the laboratory characterization, in situ tests in real conditions should be performed. An electrochemical system to measure the macrocell current density (i gal) was designed to evaluate the degradation of HDGS coated samples with different organic-inorganic hybrid films, embedded in mortar during 70 days, using an automatic data acquisition system. This system revealed to be feasible and highly sensitive to coatings degradation. Also, allow distinguishing different hybrid coatings with different thicknesses.

  13. Physicochemical foundation of steel protection against sulfide corrosion cracking

    International Nuclear Information System (INIS)

    Essentially new notions on physical-chemical mechanism of hydrogen absorption and steel sulfide corrosion cracking are formulated. The quantitative evaluation of various factors impact (the nature of chemical process on the steel surface, temperature, hydrogen sulfide partial pressure in the working medium) on hydrogen content in the steel and consequently on its tendency to cracking is accomplished within the frames of these notions. 12 refs.; 1 fig.; 1 tab

  14. Corrosion protection of steels by a cover of concrete made of fly ash and sewing dust

    Energy Technology Data Exchange (ETDEWEB)

    Vlastnik, J.; Kika, Z.; Sestak, S.

    1982-04-01

    This paper evaluates protective properties of concrete (Czechoslovakian patent no. 166 923) made of fly ash from fossil-fuel power plants and of sewing dust under conditions of underground coal mines. Steel plates (50 x 50 x 2 mm) were covered by concrete. Thickness of concrete layers (which form a sandwich with steel plate in between) ranged from 30 to 5 mm. Concrete samples (145) were placed in a 3% water solution of sodium chloride. Steel corrosion was determined after 90, 180, 270 or 365 days. Corrosion degree was compared to steel samples without concrete protection. Results are given in 2 tables. Analyses show that the concrete guarantees perfect protection of steel from corrosion for 180 days. Corrosive damage to the unprotected steel samples in the same time amounts to 800 g/m/sup 2/. In 365 days damage to steel samples protected by the concrete is insignificant, whereas corrosion of unprotected steel increases to 3,000 g/m/sup 2/. It is maintained that the concrete protection tested under laboratory conditions should guarantee efficient corrosion protection of steel 20 to 30 years.

  15. Corrosion and cathodic protection of carbon steel in the tidal zone: Products, mechanisms and kinetics

    International Nuclear Information System (INIS)

    Highlights: • The corrosion product layer forming in the tidal zone is mainly made up of magnetite. • A thin film of magnetite is formed on the steel surface under cathodic protection. • Magnetite is formed during cathodic protection under the calcareous deposit. • Pre-existing corrosion product layers are almost not modified by cathodic protection. - Abstract: Carbon steel coupons were set in the tidal zone of a French seaport for 7 years with or without cathodic protection. The average corrosion rates decreased from 90 ?m yr?1 to 9 ?m yr?1 under cathodic protection. The corrosion product layers covering the unprotected coupons, characterized by Raman spectroscopy and X-ray diffraction, were mainly made up of magnetite and Fe(III) oxyhydroxides, with magnetite being clearly predominant. The products of the residual corrosion process under cathodic protection, similar to those observed at open circuit potential, formed a thin layer on the steel surface under the calcareous deposit

  16. Protection of steel from carbon dioxide corrosion with volatile inhibitors. I. Liquid phase

    International Nuclear Information System (INIS)

    It is shown that many known inhibitors of the steel atmospheric and hydrosulfide corrosion in the electrolytes, containing CO2, are inefficient. The new inhibitors IFKhAN-72 and IFKhAN-74 with high passivation capacity are efficient ones. The IFKhAN-72 inhibitor exceeds by its protective properties the best of the studied inhibitors of the amines-type- the amines A. Through delaying both electrode reactions suppresses the steel corrosion within the wide temperature range. It manifests thereby prolonged aftereffect and due to its high penetrating capacity it protects also the steel covered with the corrosion products

  17. Synthesizing and Characterizing a Waterborne Polyaniline for Corrosion Protection of Steels

    Science.gov (United States)

    Pan, Tongyan; Yu, Qifeng; Miao, Tao

    2015-02-01

    This study explores the idea of synthesizing and characterizing a new intrinsically conducting polyaniline that at the molecular level carries a hydrophilic component, making the polymer highly waterborne and thereby applicable to massive production for corrosion protection of steels. The waterborne polyaniline was mixed in a water-based epoxy and then coated on SAE 1008/1010 steel samples for evaluating its anti-corrosion capacity using a powerful surface-analysis tool, Scanning Kelvin Probe Force Microscopy (SKPFM). The high resolution surface topography and corrosion potential of steel samples coated with the Polyaniline-based primer, as studied by SKPFM, show significantly lower corrosion activities than two control groups: uncoated steel samples and epoxy-only coated samples that were also subjected to SKPFM analyses under the same corrosive condition. The surface analysis results indicate that this new waterborne polyaniline is capable of protecting steels from corrosion when mixed in conventional water-based epoxies, opening the door to the development of an economical and long-life coating for corrosion protection of steel structures.

  18. Optimization of protective atmosphere for heat treatment of corrosion resistant steels

    International Nuclear Information System (INIS)

    Investigations are carried out for the optimization of protective atmospheres for thermal treatment of corrosion resistant steels - chromium chromium-nickel ones. Experiments are performed in the foil of different corrosion resistant alloys temperatre of thermal treatment is corresponding to the quenching temperature for these steels. Samples were held for 2-30 min. Corrosion resistance tests are conducted in 30% boiling nitric acid after thermal treatment. It is shown that at short-term hold (less than 2 min.) it is advisable to use nitrogen-containing atmospheres, while at long-term hold it is advisable to use the atmosphere of dry hydrogen as the protective one

  19. Corrosion protection of carbon steel by an epoxy resin containing organically modified clay

    OpenAIRE

    Hang, To Thi Xuan; Truc, Trinh Anh; Nam, Truong Hoai; Oanh, Vu Ke; Jorcin, Jean-Baptiste; Pébère, Nadine

    2007-01-01

    This study focusses on the use of montmorillonite clay (MMT) treated with an organic compound (aminotrimethylphosphonic acid (ATMP)) and dispersed in an epoxy resin to improve corrosion protection of carbon steel. X-ray diffraction was performed to verify that the individual silicate layers were separated and dispersed in the epoxy resin. Corrosion resistance of the coated steel was evaluated by electrochemical impedance spectroscopy (EIS) and local electrochemical impedance spectroscopy (LEI...

  20. Electrodeposition of zinc-doped silane films for corrosion protection of mild steels

    International Nuclear Information System (INIS)

    Highlights: ? Metallic zinc is doped into organosilane films by one-step electrodeposition. ? The composite films exhibit the improved corrosion resistance of mild steels. ? Zinc-doping provides additional cathodic protection to the mild steels. - Abstract: Organosilane/zinc composite films are prepared by one-step electrodeposition onto cold-rolled steels for corrosion protection. Electrochemical impedance spectroscopy measurement, bulk solution immersion and wet heat tests all show that the composite films have improved corrosion performance. X-ray photoelectron spectroscopy measurement suggests the successful encapsulation of metallic zinc. The embedding of metallic zinc results in negative shift in open-circuit potential of the film-covered electrodes. Such cathodic protection effect given by the metallic zinc provides the improved corrosion resistance of the composite films.

  1. The application of thermal spraying for corrosion protection of large steel parts used in special buildings

    International Nuclear Information System (INIS)

    An aluminium spraying procedure is presented for obtaining high-quality long-life corrosion protection for large steel parts used in special buildings in nuclear power plant construction. The advantage of a stationary metal arc spraying installation in the prefabrication of the steel parts is described. At the erection site field welds have to be metal sprayed

  2. Corrosion Protection Service Life of Epoxy-Coated Reinforcing Steel in Virginia Bridge Decks

    OpenAIRE

    Michael C. Brown; Weyers, Richard E.; Megan C. Wheeler

    2003-01-01

    The corrosion protection service life extension provided by epoxy-coated reinforcement (ECR) was determined by comparing ECR and bare steel bars from 10 Virginia bridge decks built between 1981 and 1995. The objective was to determine the corrosion protection service life time extension provided by ECR field specimens with various degrees of coating adhesion: disbonded, partially disbonded, and wholly bonded coatings. The size and length distributions of cracks in Virginia bridge decks were i...

  3. Evaluation of the effectiveness of selected corrosion inhibitors for protection of prestressing steels in PCPVs

    International Nuclear Information System (INIS)

    The corrosion protection provided prestressing steel by portland cement-based grout in the presence of sulfide, nitrate, and chloride ion environments was evaluated. Results were compared to those obtained from selected, commercially available petroleum-microcrystalline waxes (petrolatums) compounded with organic corrosion inhibitors. The investigation was conducted in two phases: (1) a review of literature to establish the mechanisms of prestressing steel corrosion, techniques available for protection of prestressing steel in hostile environments, and the performance of structures that have utilized either nongrouted- or grouted-tendon prestressing systems; and (2) a laboratory study to develop relative performance data for portland cement grout and selected commercial petroleum-based greases and waxes containing inhibitors. Conclusions derived from the investigation indicate that (1) sulfide, nitrate, and chloride salts must be excluded from prestressing materials; (2) prestressing materials must be continuously protected from inimical environments; (3) the effectiveness of the protection provided by both the organic- and cement-based corrosion inhibitors is reduced unless the steel is completely covered; and (4) both cement- and organic-based corrosion inhibitors completely protect prestressing materials when properly applied

  4. Diffusion coatings for the high temperature corrosion protection of 9-12% Cr steels

    Energy Technology Data Exchange (ETDEWEB)

    Rohr, V.; Donchev, A.; Schuetze, M. [Karl-Winnacker-Institut der DECHEMA e.V., Theodor-Heuss-Allee 25, D-60486 Frankfurt am Main (Germany)

    2004-07-01

    9-12 % Cr steels are of high interest for the application as heat-exchanger tubes in power generation stations. Indeed they possess a high thermal conductivity and favourable mechanical properties at temperatures up to 650 deg. C. However, even though conventional ferritic-martensitic 9-12 % Cr steels are from a mechanical point of view designed for service temperatures up to 650 deg. C, their use at such high temperatures is rather limited in corrosive environments. One solution could consist in protecting these steels by suitable corrosion resistant coatings. Pack cementation is one of the easiest and cheapest coating processes for high temperature applications. Yet, for ferritic-martensitic steels, the coating temperature can lie at 650 deg. C maximum. Above this limit, the decomposition of the martensite is accelerated, and the mechanical properties of the material would be deteriorated. The present work consisted in coating the 9 % Cr steel P91 and the 12 % Cr steel HCM12A without modifying their microstructure. Therefore, the coating process was either carried out at 650 deg. C or combined with the heat treatment of the ferritic-martensitic steel. Due to the low coating temperature, aluminide coatings were developed first. Later, a two step Cr+Al coating was obtained. The corrosion resistance of the developed coatings was tested at 650 deg. C for 1000 h in a simulated coal firing atmosphere composed of: 14 % CO{sub 2}, 10 % H{sub 2}O, 1 % O{sub 2}, 0.1 % SO{sub 2}, 0.01 % HCl (bal. N{sub 2}). The corrosion behaviour of the coated samples showed a better resistance than the bare materials. Furthermore, the comparison was extended to aluminide coatings obtained by Fluidized Bed Chemical Vapour Deposition (FBCVD) on 9-12 % Cr steels. Eventually, the corrosion resistance was compared with bare and coated austenitic steels as well as the nickel-based alloy IN 617. (authors)

  5. Indium oxide thin film as potential photoanodes for corrosion protection of stainless steel under visible light

    International Nuclear Information System (INIS)

    Graphical abstract: If the conduction band potential of In2O3 is more negative than the corrosion potential of stainless steel, photo-induced electrons will be transferred from In2O3 to the steel, thus shifting the potential of the steel into a corrosion immunity region and preventing the steel from the corrosion. - Highlights: • Indium oxide performed novel application under visible light. • Indium oxide by sol–gel method behaved better photoelectrochemical properties. • Electrons were transferred to stainless steel from indium oxide once light on. - Abstract: This paper reports the photoelectrochemical cathodic protection of 304 stainless steel by In2O3 thin-film under visible-light. The films were fabricated with In2O3 powders, synthesized by both sol–gel (In2O3-sg) and solid-state (In2O3-ss) processes. The photo-induced open circuit potential and the photo-to-current efficiency measurements suggested that In2O3 could be a promising candidate material for photoelectrochemical cathodic protection of metallic alloys under visible light. Moreover, the polarization curve experimental results indicated that In2O3-sg thin-film can mitigate the corrosion potential of 304 stainless steel to much more negative values with a higher photocurrent density than the In2O3-ss film under visible-light illumination. All the results demonstrated that the In2O3-sg thin-film provides a better photoelectrochemical cathodic protection for 304 stainless steel than In2O3-ss thin-film under visible-light illumination. The higher photoelectrochemical efficiency is possibly due to the uniform thin films produced with the smaller particle size of In2O3-sg, which facilitates the transfer of the photo-induced electrons from bulk to the surface and suppresses the charge recombination of the electrons and holes

  6. Corrosion protection properties of hydroxamic acid self-assembled monolayer on carbon steel

    International Nuclear Information System (INIS)

    Self assembled monolayers (SAMs) of hydroxamic acids CH3(CH2)nCONHOH with different alkyl length were formed on the carbon steel electrode surface. The corrosion protection properties of the monolayers were examined and characterized by electrochemical polarization curves, electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy (XPS) and contact angle measurements. XPS results showed that the hydroxamic acid molecules adsorbed on the carbon steel surface, and the contact angle values on the modified surface supported the formation of hydrophobic hydroxamic acid SAMs. The results of electrochemical studies showed that the values of the corrosion potential shift towards the positive direction, and anodic currents of the carbon steel dissolution significantly decreases, indicating that hydroxamic acids are anodic inhibitors. However, the chain length and assembling time influence the protection efficiency

  7. Corrosion protection properties of hydroxamic acid self-assembled monolayer on carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Alagta, Abdulmajed [Chemical Research Centre of the Hungarian Academy of Science, Department of Surface Modification and Nanostructures, Pusztaszeri ut 59-67, H-1025 Budapest (Hungary)], E-mail: alagata@chemres.hu; Felhoesi, Ilona [Chemical Research Centre of the Hungarian Academy of Science, Department of Surface Modification and Nanostructures, Pusztaszeri ut 59-67, H-1025 Budapest (Hungary); Bertoti, Imre [Chemical Research Centre of the Hungarian Academy of Science, Institute of Materials and Environmental Chemistry, Pusztaszeri ut 59-67, H-1025 Budapest (Hungary); Kalman, Erika [Chemical Research Centre of the Hungarian Academy of Science, Department of Surface Modification and Nanostructures, Pusztaszeri ut 59-67, H-1025 Budapest (Hungary)

    2008-06-15

    Self assembled monolayers (SAMs) of hydroxamic acids CH{sub 3}(CH{sub 2}){sub n}CONHOH with different alkyl length were formed on the carbon steel electrode surface. The corrosion protection properties of the monolayers were examined and characterized by electrochemical polarization curves, electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy (XPS) and contact angle measurements. XPS results showed that the hydroxamic acid molecules adsorbed on the carbon steel surface, and the contact angle values on the modified surface supported the formation of hydrophobic hydroxamic acid SAMs. The results of electrochemical studies showed that the values of the corrosion potential shift towards the positive direction, and anodic currents of the carbon steel dissolution significantly decreases, indicating that hydroxamic acids are anodic inhibitors. However, the chain length and assembling time influence the protection efficiency.

  8. The Effect of Oil on Carbon Dioxide Corrosion Inhibition on Carbon Steel - Potential for Improved Corrosion Protection

    OpenAIRE

    Foss, Martin Smedstad

    2010-01-01

    The search for robust and cost efficient ways to prevent internal corrosion of carbon steel piping and equipment in oil and gas production and transportation has lead to the development of highly sophisticated CO2 corrosion inhibitor products. This thesis studies oil wetting and corrosion inhibitor performance on bare steel and steel with corrosion product deposits on the surface, in the presence of a refined, low aromatic hydrocarbon oil. Three surfactants were used in...

  9. Electrochemical synthesis and characterisation of hybrid materials polypyrrole/dodecatungstophosphate as protective agents against steel corrosion

    Science.gov (United States)

    Bonastre Cano, Jose Antonio

    The losses caused by the effect of the corrosion are of the order of 2-3,5% of the GDP of the developed countries or developing only in direct costs, losses in structures or products. This figure doubles by the indirect costs, losses of productivity or demands for delays. Beside the possible losses of human lives, any intent leaded to the decrease of the corrosion in rusty metals is a commendable objective from the point of view of the protection of the environment. Building industry employing reinforced concrete is able to project some structural elements (pillars, wrought, beam, etc.) in principle free of corrosion, assuring during many years the useful life of the work in service. However, the reinforced concrete would be' a perfect solution if the indefinite permanency of the passive state of the steel could be guaranteed. Indeed, although the steel is protected against corrosion due to basic pH which provides the cement, the severe action of saline media or the effect of CO2 can diminish this protection conditions beginning the corrosion in steel elements. Type-p doped conducting polymers, as polypyrrole, are firm candidates to protect carbon steel providing galvanic protection by stabilising the passive layer of Fe oxides initially grown. Doping the polymeric matrix with polioxometalates, concretely phosphotungstate PW12O403-, is a very interesting hypothesis due to their oxidising effect, improving the anodic protection by the hybrid material electrosynthesised on carbon steel substrate. First in the present work, a new method was developed by cyclic voltammetry in LiClO4 + acetonitrile medium in order to diminish the unavoidable oxidation of carbon steel when the electrosyntesis of the hybrid material polypyrrole/PW12O403- is carrying out. The beginning potential of polypyrrole polymerisation is about 0.8 V (vs. Ag/AgCl), a positive potential where oxidation of Fe substrate is high, not allowing the electrodeposition of the hybrid material. On the other hand, this pretreatment should guarantee appropriate conditions in order to obtain a coating with high adhesion on carbon steel. Once studied the better parameters for the synthesis of the hybrid material by cyclic voltammetry, hybrid material is morphological, chemical and electrochemical characterised by the following techniques: Cyclic Voltammetry, Scanning Electron Microscopy, Energy Dispersive X Ray, X Ray Photoelectron Spectroscopy and Electrochemical Impedance Spectroscopy. The hybrid material polypyrrole/PW 12O403-. chemical structure presents Fe oxides and hydroxide within the polypyrrole polycationic matrix. Hybrid material polypyrrol/PW12O403- diminishes the corrosion of carbon steel in NaOH and Porland cement filtering solutions. These cement solutions simulate the pore fluid conditions existing in cured mortar or concrete elements. Fe ion concentration data were determinated in corrosion tests. Voltammetric response of polymeric coatings was evaluated by cyclic voltammetry. Finally, the protection provided by hybrid material polypyrrole/PW 12O403, in oxidised and reduced state, was evaluated on carbon steel electrodes embedded in Portland cement mortars immersed in seawater and submitted to an accelerated carbonation process for 265 days. Polymeric material covered carbon steel electrodes in reduced state suffer a Fe gravimetric loss 15 times lower than the ones of bare electrodes against chlorides attack, due to the effect of physical barrier. Hybrid material covered electrodes in oxidised state after being submitted to a carbonation process suffer a Fe gravimetric loss 2.5 times lower than the ones of bare electrodes, due to galvanic protection provided by hybrid material polypyrrole/PW 12O403- on carbon steel.

  10. Polybenzoxazine/SiO2 nanocomposite coatings for corrosion protection of mild steel

    International Nuclear Information System (INIS)

    Highlights: •Corrosion resistance of the coating was improved using SiO2 nanoparticles. •Morphology and wetting properties were studied upon electrochemical behavior. •Interfacial interactions were enhanced by the reaction between two phases. -- Abstract: A series of nanocomposite coatings (PBS) consisting of silane functional polybenzoxazine (PB-TMOS) and SiO2 nanoparticles were developed for corrosion protection of mild steel. The influence of silica content on corrosion resistance of PBS coatings was investigated by electrochemical measurements. The surface chemistry of nanoparticles and its effect on morphology of the PBS coating was also studied utilizing Fourier Transforms Infrared Spectroscopy, 29Si Nuclear Magnetic Resonance and Scanning Electron Microscopy analyses. The results indicate that the presence of the covalent bond between nanoparticles and PB-TMOS, greatly improves the interfacial interactions at the polymer/filler interfaces resulting in a better corrosion performance

  11. Stoichiometric titanium dioxide ion implantation in AISI 304 stainless steel for corrosion protection

    Science.gov (United States)

    Hartwig, A.; Decker, M.; Klein, O.; Karl, H.

    2015-12-01

    The aim of this study is to evaluate the applicability of highly chemically inert titanium dioxide synthesized by ion beam implantation for corrosion protection of AISI 304 stainless steel in sodium chloride solution. More specifically, the prevention of galvanic corrosion between carbon-fiber reinforced plastic (CFRP) and AISI 304 was investigated. Corrosion performance of TiO2 implanted AISI 304 - examined for different implantation and annealing parameters - is strongly influenced by implantation fluence. Experimental results show that a fluence of 5 × 1016 cm-2 (Ti+) and 1 × 1017 cm-2 (O+) is sufficient to prevent pitting corrosion significantly, while galvanic corrosion with CFRP can already be noticeably reduced by an implantation fluence of 5 × 1015 cm-2 (Ti+) and 1 × 1016 cm-2 (O+). Surface roughness, implantation energy and annealing at 200 °C and 400 °C show only little influence on the corrosion behavior. TEM analysis indicates the existence of stoichiometric TiO2 inside the steel matrix for medium fluences and the formation of a separated metal oxide layer for high fluences.

  12. Electrodeposition of Zn-Ni coatings as Cd replacement for corrosion protection of high strength steel

    International Nuclear Information System (INIS)

    Research highlights: ? Electrodeposition of Zn-Ni coatings from an alkaline bath on a high strength steel. ? Complete characterisation of the coatings (corrosion, morphology and composition). ? Correlation of the electrodeposition conditions with the properties of the film. ? Similar corrosion resistance than Zn-Ni coatings deposited from acidic baths. ? Lower hydrogen content incorporated than for a post baked cadmium-coated steel. - Abstract: Electrodeposition of Zn-Ni coatings performed in acidic baths are not suitable for high strength steels due to their high susceptibility to hydrogen embrittlement. In this work, Zn-Ni coatings were deposited on a high strength steel (4340) upon stirring conditions from an alkaline bath. A complete characterisation of the coatings (corrosion, morphology and composition) has been accomplished, correlating the electrodeposition conditions with these features. The best protective properties of the grown coatings were achieved for the alloys with a single phase structure of ?-Ni5Zn21 and a denser morphology. Additionally, the hydrogen content incorporated is lower than even cadmium-coated 4340 steel which has undergone a postbaking dehydrogenation treatment.

  13. Aluminium electroplated from ionic liquids as protective coating against steel corrosion

    International Nuclear Information System (INIS)

    The protective action of thin layers of aluminium electroplated on a carbon steel (UNI Fe360B) has been studied. The coatings were obtained via electroreduction, at room temperature, from an ionic liquid constituted by 1-butyl-3-methyl-imidazolium heptachloroaluminate. Coatings of different thickness, ranging from 10 to 40 ?m, were obtained. Their morphology and chemical composition were investigated using SEM microscopy coupled with EDX microanalysis and X-ray diffraction. Electrochemical tests (potentiodynamic polarization curves, open-circuit potential and electrochemical impedance spectroscopy) were performed in order to characterise the corrosion resistance of the coating in 3.5% NaCl aqueous solution. Visual investigation of the samples during long term of exposition to neutral salt spray gave an evaluation of their free corrosion properties. It was found that the aluminium layers deposited from ionic liquids significantly protect the substrate from the general corrosion and this action increases with the coating thickness

  14. Indium oxide thin film as potential photoanodes for corrosion protection of stainless steel under visible light

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yan [Key Laboratory of New Fiber Materials and Modern Textile, Qingdao University, 308 Ningxia Road, Qingdao 266071 (China); Yu, Jianqiang, E-mail: jianqyu@qdu.edu.cn [Key Laboratory of New Fiber Materials and Modern Textile, Qingdao University, 308 Ningxia Road, Qingdao 266071 (China); Sun, Kai; Zhu, Yukun [Key Laboratory of New Fiber Materials and Modern Textile, Qingdao University, 308 Ningxia Road, Qingdao 266071 (China); Bu, Yuyu; Chen, Zhuoyuan [National Engineering Center of Marine Corrosion Protection, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071 (China)

    2014-05-01

    Graphical abstract: If the conduction band potential of In{sub 2}O{sub 3} is more negative than the corrosion potential of stainless steel, photo-induced electrons will be transferred from In{sub 2}O{sub 3} to the steel, thus shifting the potential of the steel into a corrosion immunity region and preventing the steel from the corrosion. - Highlights: • Indium oxide performed novel application under visible light. • Indium oxide by sol–gel method behaved better photoelectrochemical properties. • Electrons were transferred to stainless steel from indium oxide once light on. - Abstract: This paper reports the photoelectrochemical cathodic protection of 304 stainless steel by In{sub 2}O{sub 3} thin-film under visible-light. The films were fabricated with In{sub 2}O{sub 3} powders, synthesized by both sol–gel (In{sub 2}O{sub 3}-sg) and solid-state (In{sub 2}O{sub 3}-ss) processes. The photo-induced open circuit potential and the photo-to-current efficiency measurements suggested that In{sub 2}O{sub 3} could be a promising candidate material for photoelectrochemical cathodic protection of metallic alloys under visible light. Moreover, the polarization curve experimental results indicated that In{sub 2}O{sub 3}-sg thin-film can mitigate the corrosion potential of 304 stainless steel to much more negative values with a higher photocurrent density than the In{sub 2}O{sub 3}-ss film under visible-light illumination. All the results demonstrated that the In{sub 2}O{sub 3}-sg thin-film provides a better photoelectrochemical cathodic protection for 304 stainless steel than In{sub 2}O{sub 3}-ss thin-film under visible-light illumination. The higher photoelectrochemical efficiency is possibly due to the uniform thin films produced with the smaller particle size of In{sub 2}O{sub 3}-sg, which facilitates the transfer of the photo-induced electrons from bulk to the surface and suppresses the charge recombination of the electrons and holes.

  15. Corrosion Protection of Carbon Steel Using Poly aniline Composite with Inorganic Pigments

    International Nuclear Information System (INIS)

    Two inorganic pigments (TiO2 and SiO2) were used to prepare composites with poly aniline (PANI) by situ polymerization method. PANI and PANI composites with SiO2 and TiO2 were characterized using Fourier transform infrared spectroscopy and X-ray diffraction. The morphology of the synthesized pigments (PANI , PANI-SiO2 and PANI-TiO2) was examined using scanning electron microscopy. Samples were then used as pigments through blending them with acrylic paint and applied on the surface of carbon steel panels. Corrosion was evaluated for coating of carbon steel panels through full immersion test up to standard ASTMG 31. Mass loss was calculated after they have been exposed in acidic media. A digital camera was also used for monitoring corrosion visually on the surface of carbon steel specimens. The results revealed that acrylic paint pigmented by PANI-SiO2 composite was more efficient in corrosion protection for carbon steel compared with the other synthesized pigments. (author)

  16. Characterization of organic-inorganic hybrid coatings for corrosion protection of galvanized steel and electroplated ZnFe steel

    Directory of Open Access Journals (Sweden)

    Maria Eliziane Pires de Souza

    2006-03-01

    Full Text Available The development of hybrids materials has been extensively investigated in recent years. The combination of a wide variety of compositions and production processes had permitted the use of these materials in different applications like coatings for corrosion protection of metals. In this work organic-inorganic hybrid materials have been prepared from the hydrolysis of tetraethylorthosilicate and silanol-terminated polidymetilmetoxysilane using a sol-gel process. These materials have been applied on galvanized steel and on steel electroplated with a ZnFe. In order to evaluate the degradation behavior of these coatings, electrochemical techniques (Electrochemical Impedance Spectroscopy and Potentiodynamic Polarization were used. EIS data was fitted to an equivalent circuit from which the electrochemical parameters were obtained. Results show a good protective character of the hybrid films, when compared with uncovered specimens. The overall performance of the coating systems appears to be highly dependent on the kind of metallic coating applied to the steel.

  17. Interaction of Benzimidazoles and Benzotriazole: Its Corrosion Protection Properties on Mild Steel in Hydrochloric Acid

    Science.gov (United States)

    Ramya, K.; Mohan, Revathi; Joseph, Abraham

    2014-11-01

    Synergistic hydrogen-bonded interaction of alkyl benzimidazoles and 1,2,3-benzotrizole and its corrosion protection properties on mild steel in hydrochloric acid at different temperatures have been studied using polarization, EIS, adsorption, surface studies, and computational methods. The extent of synergistic interaction increases with temperature. Quantum chemical approach is used to calculate some electronic properties of the molecules and to ascertain the synergistic interaction, inhibitive effect, and molecular structures. The corrosion inhibition efficiencies and the global chemical reactivity relate to some parameters, such as total energy, E HOMO, E LUMO, and gap energy (? E). 1,2,3-Benzotrizole interacts with benzimidazoles derivatives up to a bond length of approximately 1.99 Å. This interaction represents the formation of a hydrogen bond between the 1,2,3-benzotrizole and benzimidazoles. This synergistic interaction of 1,2,3-benzotrizole and benzimidazole derivatives offers extended inhibition efficiency toward mild steel in hydrochloric acid.

  18. The study of the corrosion protection of the low-carbon steel using film-products

    International Nuclear Information System (INIS)

    The paper reports studies on the efficiency of the film-inhibitors that covered low-carbon steel placed in a humid medium, and also, the optimization of the working conditions to improve the resistance to corrosion. The analyzes were done in the Industrial Physical - Chemical Laboratories of INSA - Lyon by electrochemical stationary techniques. The experimental device was a potentiometer of type EGG PAR (Princeton Applied Research). It was connected with a computer and three potential electrodes introduced in a cell with NaCl 30 g/l solution to acquire the data and to process the information. The film-products used were organic hydrosoluble polymers with diphosphonic 'heads' that permit a very good absorption at the metallic surface. This research is used to protect the installations of low-carbon steel against the atmospheric and high temperature corrosion. (authors)

  19. On the inhibitor protection of high-strength steels from corrosion cracking on the crack propagation stage

    International Nuclear Information System (INIS)

    Possibilities of applying inhibitors to protect high-strength steels from corrosion crack growth in water medium, are studied. Mechanisms of their effect are investigated. Tests are carried out using the heat treated 45KhN2MFA steel (tempering 200 deg C) at the temperature of 25 deg C using beam samples (12x18x160 mm). It is shown that inhibitor protection of high-strength steels from corrosion cracking is a prospective way of increasing their corrosion crack resistance. Oxoanions are inhibitors of crack growth if they are reduced during adsorption, absorbing hydrogen ions. Inhibitors of the ICG type (inhibitors of crack growth) which suppress the process of hydrogen discharge - is a highly effective means of increasing corrosion crack resistance of high-strength alloys in the water medium. The effectiveness of inhibitors considered proves the hydrogen mechanism of water medium effect on crack growth in high-strength steels

  20. POLYPHENYLENESULFIED/MONTOMORILLONITE CLAY NANOCOMPOSITE COATINGS: THEIR EFFICACY IN PROTECTING STEEL AGAINST CORROSION.

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA, T.; GAWLIK, K.

    2006-06-01

    Nanoscale montomorillonite (MMT) clay fillers became dispersed in a polyphenylenesulfied (PPS) matrix through the processes of octadecylamine (ODA) intercalation {yields} molten PPS co-intercalation {yields} exfoliation. Cooling this molten exfoliated material led to the formation of a PPS/MMT nanocomposite. The MMT nanofiller conferred three advanced properties on the semi-crystalline PPS: First, it raised its melting point by nearly 40 C to 290 C; second, it increased its crystallization energy, implying that an excellent adherence of the nanofillers surfaces to PPS in terms of a good interfacial bond; and, third, it abated the degree of its hydrothermal oxidation due to sulfide {yields} sulfite linkage transformations. When this advanced PPS nanocomposite was used as a corrosion-preventing coating for carbon steel in a simulated geothermal environment at 300 C, a coating of {approx}150 {micro}m thickness adequately protected the steel against hot brine-caused corrosion. In contrast, an MMT-free PPS coating of similar thickness was not nearly as effective in mitigating corrosion as was the nanocompsite; in fact, the uptake of corrosive ionic electrolyte by the unmodified coating increased with an extending exposure time.

  1. Self-immunity microcapsules for corrosion protection of steel bar in reinforced concrete

    Science.gov (United States)

    Wang, Yanshuai; Fang, Guohao; Ding, Weijian; Han, Ningxu; Xing, Feng; Dong, Biqin

    2015-12-01

    A novel microcapsule-based self-immunity system for reinforced concrete is proposed. Its feasibility for hindering the corrosion of steel rebar by means of lifting the threshold value of [Cl?]/[OH?] is discussed. Precisely controlled release behavior enables corrosion protection in the case of depassivation. The release process is characterized over a designated range of pH values, and its release characteristics of the microcapsules, triggered by decreasing pH value, are captured by observing that the core crystals are released when exposed to a signal (stimulus). The aim of corrosion protection of steel bar is achieved through the constantly-stabilized passive film, and its stability is promoted using continuous calcium hydroxide released from the microcapsule, restoring alkaline conditions. The test results exhibited that the release process of the microcapsules is a function of time. Moreover, the release rate of core materials could interact with environmental pH value, in which the release rate is found to increase remarkably with decreasing pH value, but is inhibited by high pH levels.

  2. Electrochemical determination of the minimum cathodic protection potential and underground steel corrosion rate. On the moderate criteria for the protection efficiency

    International Nuclear Information System (INIS)

    Experimentally are determined the minimum protection potential Emin and steel corrosion rate in a number of soils by means of calculation using the cathode polarization curve. Their correlation is shown with results of weight tests in conditions of the free corrosion and cathode polarization. It is shown too that Emin is not connected directly with the steel free corrosion rate but when lowering Emin normally is decreased. Using Emin as a characteristic for the soil corrosion effect and features of the cathode protection when softening the criteria of its efficiency are discussed. 21 refs., 4 figs., 2 tabs

  3. Corrosion protection of low-carbon steel using exopolysaccharide coatings from Leuconostoc mesenteroides

    Science.gov (United States)

    Corrosion is one of the most serious and challenging problems faced worldwide by industry. This research investigates the inhibition of corrosive behavior of SAE1010 steel by bacterial exopolysaccharides. Electrochemical Impedance Spectroscopy was used to evaluate the corrosion inhibition of diffe...

  4. Study on cerium-doped nano-TiO2 coatings for corrosion protection of 316?L stainless steel

    OpenAIRE

    Li, Suning; Wang, Qian; Chen, Tao; Zhou, Zhihua; Wang, Ying; Fu, Jiajun

    2012-01-01

    Many methods have been reported on improving the photogenerated cathodic protection of nano-TiO2 coatings for metals. In this work, nano-TiO2 coatings doped with cerium nitrate have been developed by sol–gel method for corrosion protection of 316?L stainless steel. Surface morphology, structure, and properties of the prepared coatings were investigated by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy. The corrosion p...

  5. Electrochemical Impedance Spectroscopy Study on Corrosion Protection of Acrylate Nanocomposite on Mild Steel Doped Carbon Nanotubes

    Science.gov (United States)

    Mahmud, M. R.; Akhir, M. M.; Shamsudin, M. S.; Afaah, A. N.; Aadila, A.; Asib, N. A. M.; Alrokayan, Salman A. H.; Khan, Haseeb A.; Harun, M. K.; Rusop, M.; Abdullah, S.

    2015-05-01

    Acrylate:carbon nanotubes (A:CNTs) nanocomposite thin film was prepared by sol- gel technique. The corrosion coating protection of acrylate:carbon nanotubes (CNTs) nanocomposite thin film has been coated on mild steel characterised by electrochemical impedance spectrometer (EIS) measurement and equivalent circuit model are employed to analyse coating impedance for corrosion protection. In this study, 3.5 w/v % sodium chloride (NaCl) solution was immersed the acrylate:carbon nanotubes nanocomposite thin film. As the results, the surface morphology were found that there formation of carbon nanotubes with good distribution on acrylate-based coating. From EIS measurement, A:CNTs nanocomposite thin film with 0.4 w/v % contain of CNTs was exhibited the highest coating impedance from Nyquist graph after immersed in sodium chloride solution and may provide the excellent corrosion protection. The Bode plots have shown the impedance is high at the beginning from the time at high frequency and slightly decreases with value of frequency become smaller.

  6. Use of Extracted Green Inhibitors as a Friendly Choice in Corrosion Protection of Low Alloy Carbon Steel

    Directory of Open Access Journals (Sweden)

    Jano, A.

    2012-11-01

    Full Text Available Mitigation of corrosion impact on environment is an important step in environmental protection. Use of environmentally friendly corrosion protection methods is very important. It is smart to choose cheap and safe to handle compounds as corrosion inhibitors. The use of green inhibitors (extracted inexpensively, from the seed endosperm of some Leguminosae plants, and investigation of their efficiency in corrosion protection is the aim of this study. As green inhibitor one kind of polysaccharides (galactomannan from locust bean gum (also known as carob gum, carob bean gum extracted from the seed of carob tree is used. Corrosion protection efficiency of these extracted green inhibitors was tested for carbon steel marked as: steel 39, steel 44, and iron B 500 (usually applied as reinforcing bars to concrete. Sulfuric acid solution in the presence of chloride ions was used as corrosion media. The composition of corrosion acid media used was 1 mol L-1 H2SO4 and 10-3 mol L-1 Cl- (in the form of NaCl. Electrochemical techniques such as potentiodynamic polarization methods were used for inhibitor efficiency testing.

  7. Method and laboratory unit for simultaneous rapid control of corrosion, hydrogen pickup, and steel protection upon acid etching

    International Nuclear Information System (INIS)

    A method and laboratory unit for simultaneous rapid control of corrosion, hydrogen absorption and steel protection upon acid etching is described. The development addition FAUM -1 ( components, % mass. : 10 phenol, 25 aniline, 60 urotropin and 5 cupric chloride), put into a hydrochloric acid solution in amounts of 10 g/l was used as a corrosion inhibitor and also for carbon steel (St.3) hydridation. 30 identical steel membranes were used. It is pointed out that the FAUM-1 inhibitor is quite good at showing simultaneously anticorrosion as well as anti-hydridation properties. The time of one membrane analytical cycle may be reduced from 120 to 90 min

  8. Corrosion protection of low-carbon steel using exopolysaccharide coatings from Leuconostoc mesenteroides.

    Science.gov (United States)

    Finkenstadt, Victoria L; Côté, Gregory L; Willett, J L

    2011-06-01

    Corrosion of metals is a serious and challenging problem faced worldwide by industry. Purified Leuconostoc mesenteroides exopolysaccharide (EPS) coatings, cast from aqueous solution, inhibited the corrosion of low-carbon steel as determined by electrochemical impedance spectroscopy (EIS). There were two different corrosion behaviors exhibited when EPS films from different strains were cast onto the steel. One EPS coating reacted immediately with the steel substrate to form an iron (III) oxide layer ("rust") during the drying process while another did not. The samples that did not flash corrode had higher corrosion inhibition and formed an iron (II) passivation layer during EIS testing that persisted after the cells were disassembled. Corrosion inhibition was strain-specific as polysaccharides with similar structure did not have the same corrosion potential. PMID:21290167

  9. Thermodynamic aspects of the development of inhibitory methods of protecting steel from corrosion in salt water environments

    Directory of Open Access Journals (Sweden)

    ?.?. ??????????

    2008-04-01

    Full Text Available  The thermodynamics aspects of steel in water-salt solutions spontaneous corrosion and ways of purposeful creation of inhibition methods for its slow-down were considered. For the system Fe-H2O on the basis of diagram Pourbe analysis were determined definite ranges of potentials of metal and pH of the solutions for which corrosive destruction speed reduction were achieved. It is shown that the effective corrosion protection of steel can be achieved by means of measures which include application of inhibitors with simultaneous medium pH modification, as a result there takes place a transition of metal into a stable passivated state. Potentiostatic research of steel in water-salt solutions corrosion had confirmed efficiency of the method offered.

  10. On the protective effect of KhOSP-10 inhibitor during corrosion, hydrogenadsorption and corrosion cracking of a steel in sulfuric acid

    International Nuclear Information System (INIS)

    The protective propeties of inhibitor KhOSP-10 in the time of corrosion and corrosive cracking of steel 40Kh are higher then those of inhibitors KPI-1, KI-1, I-I-V etc. Its ability to reduce steel hydrogenation is the same as in the case of KPI-1 inhibitor i.e. below that of KI-1. HCl additives enhance the efficiency of inhibitors KPI-1, KI-1, I-1-V etc. up to the protective ability of KhOSP-10. Kinetics of the electrode processes was estimated from polarization curves

  11. Corrosion properties of steel protected by nanometre-thick oxide coatings

    International Nuclear Information System (INIS)

    Highlights: • 40–50 nm mixed alumina–tantala coatings were grown by atomic layer deposition. • Effects of substrate surface finish and oxide mix were analysed. • Nanolaminate stacks are better resistant to breakdown. • Localised corrosion occurs at pre-existing coating defects exposing substrate sites. • Substrate brushing and H2–Ar plasma pre-treatment hinder pit initiation. - Abstract: A comprehensive study of the corrosion properties of low alloy steel protected by 40–50 nm aluminium and tantalum mixed oxide coatings grown by atomic layer deposition is reported. Electrochemical and surface analysis was performed to address the effect of substrate surface finish and whether an oxide mixture or nanolaminate was used. There was no dissolution or breakdown for nanolaminate alumina/tantala stacks in acidic NaCl solution. Localised corrosion (pitting) took place when defects exposing the substrate pre-existed in the coating. Substrate pre-treatment by brushing and H2–Ar plasma was instrumental to block or slow down pit initiation by reducing the defect dimensions

  12. Corrosion Protection of Steel by Thin Coatings of Starch-oil Emulsions

    Science.gov (United States)

    Corrosion of materials is one of the most serious and challenging problems faced worldwide by industry. This research investigated the inhibition of corrosive behavior by jet-cooked starch-soybean oil composites on SAE 1010 steel. Electrochemical Impedance Spectroscopy (EIS) was used to evaluate t...

  13. Protection of steel from corrosion and hydrogen absorption by organic inhibitors: experimental and quantum-chemical studies

    Directory of Open Access Journals (Sweden)

    Beloglazov G.

    2013-01-01

    Full Text Available The step-strip anodic dissolution technique was used to obtain concentration profiles of cathodic evolved H2 across the depth of Cr-Ni1810 steel under corrosion in water-salt media in the presence of SRB. The proposed approximation of the experimentally obtained distribution of hydrogen along the depth of steel by means of standard Gaussian function made it possible to establish the integral hydrogen content of the sub-layer (up to 80 ?m with high degree of accuracy. The efficiency of protective actions of the studied organic compounds against corrosion and hydrogen absorption by steel were compared with the data of quantum chemical computations performed for isolated molecules of the studied inhibitors with the help of the MNDO method. The results obtained point to a difference in the protective mechanisms of the studies inhibitors in case of anticorrosion action and hydrogen absorption by steel.

  14. Alumina nanostructured coating for corrosion protection of 316L stainless steel

    Directory of Open Access Journals (Sweden)

    P. Doodman

    2014-03-01

    Full Text Available Nanostructured alumina thin films were coated on stainless steel by Sol-Gel dip coating method. In order to prevent crack formation, Al2O3 films were kept in a solvent bath immediately after coating to reduce the rate of drying. Effects of calcination temperature and withdrawal speed on structural properties were analyzed using XRD and SEM. Topography and thickness of coatings were analyzed by AFM. Effects of the above parameters on anticorrosion performance of coats have been evaluated through electrochemical polarization technique. The results indicated that the optimum calcination temperature to achieve the best corrosion protection was 400ºC. The thickness of one time coating with 1mm/s withdrawal speed was about 146 nm.

  15. The effect of oil on carbon dioxide corrosion inhibition on carbon steel - potential for improved corrosion protection

    International Nuclear Information System (INIS)

    The search for robust and cost efficient ways to prevent internal corrosion of carbon steel piping and equipment in oil and gas production and transportation has lead to the development of highly sophisticated CO2 corrosion inhibitor products. This thesis studies oil wetting and corrosion inhibitor performance on bare steel and steel with corrosion product deposits on the surface, in the presence of a refined, low aromatic hydrocarbon oil. Three surfactants were used in the experiments; two commercial inhibitor base chemicals; an oleic imidazoline salt (OI) and a phosphate ester (PE), and cetyl trimethyl ammonium bromide (CTAB), a well characterized quaternary ammonium compound. Adsorption characteristics of the inhibitors on corroding iron and FeCO3 particles were also studied. Polarization resistance (PR) and electrochemical impedance spectroscopy (EIS) techniques were used to study the effect of the oil on the performance of the inhibitors. The performance testing was done on corroding carbon steel without any surface deposits and on carbon steel with either ferrous carbonate (FeCO3) or ferric corrosion products on the surface. The results showed that the addition of oil in the inhibitor tests had a significant, positive effect on the performance of the two commercial corrosion inhibitors; decrease in corrosion rate of about one order of magnitude compared to the rate without oil was found. Based on the EIS data it was concluded that the improved performance was caused by a modification of the inhibitor film and not the formation of a macroscopic oil film on the steel surface. Indications of oil wetting of the steel surface were only found when ferric corrosion products were present and OI was used as the inhibitor. No such effects were seen on bare steel or on FeCO3 covered surfaces. Contact angle measurements and dispersion tests were used to investigate the effect of the inhibitors on the wettability of the three types of surfaces when they were exposed to water and oil. Both the behavior of an oil droplet on an already water-wet surface and a water droplet on an already oil wet surface were investigated to determine the ability of the inhibitors to alter the affinity of the surface to water and oil respectively. The results indicated the no hydrophilic to hydrophobic transition occurred on bare steel and FeCO3 covered steel. The testing on surfaces with ferric corrosion products revealed that a water wet to oil-wet transition was possible on the ferric deposits using both PE and OI as inhibitor. The effect was, however, significantly stronger with OI than with PE. It was also found that the addition of the two inhibitors enhanced the hydrophobic behavior of an already oil-wet surface for both bare steel and steel with FeCO3 deposits. Water droplets entrained in the oil was in these experiments not able to spread on the steel surface. Electrophoresis measurements were used to determine influence of the three inhibitors on the zetapotential of FeCO3 and corroding iron particles. The tendency of the inhibitors to adsorb on surfaces with the same charge as the head group of the inhibitor was investigated. The focus in the testing on corroding iron was to determine the suitability of zetapotential as a method for investigating surface potential of corroding surfaces. It was found that the inhibitors adsorbed on iron carbonate regardless of the surface charge on the iron carbonate. On iron particles the experiments indicated that measurements of the surface potential of corroding particles could only be done when the corrosion rate had been reduced significantly using corrosion inhibitors. (Author)

  16. Exploring new W–B coating materials for the aqueous corrosion–wear protection of austenitic stainless steel

    International Nuclear Information System (INIS)

    The material loss of metallic surfaces through corrosion–wear is a serious concern in many application sectors, ranging from bio-medical implants to marine, oil and gas field components to transport vehicle and nuclear reactor devices. In principle, self-passivating alloys, like stainless steels, can be protected from surface degradation caused by corrosion–wear through the application of protective thin, hard surface coatings. In this work the suitability of using W matrix coating materials supersaturated with varying levels of boron were applied to austenitic stainless steel substrates (Ortron 90) and assessed for this purpose. These materials were compared to a highly corrosion–wear resistant “datum” surface engineered material (CrN coated Ti–6Al–4V) in sliding contact tests against a chemically inert aluminium oxide ball, whilst immersed in 0.9% NaCl solution at 37 °C. The work demonstrated that all the coated materials to be very much more resistant to material loss through corrosion–wear (by nearly an order of magnitude) compared to uncoated stainless steel, and two coatings, W–13%B and W–23%B coated Ortron 90 were similarly resistant as CrN coated Ti–6Al–4V. Three fundamental types of corrosion–wear were discovered that represented differing levels of passive film durability. The total material loss rate (TMLR) during corrosion–wear testing showed linear proportionality with the change in open circuit potential ?OCP which obeyed the governing equation: TMLR = m ?OCP + C. - Highlights: • Magnetron sputtered W–(B) coatings displayed a crystalline to amorphous transition. • W–(B) coatings displayed excellent corrosion–wear resistance under OCP conditions. • Three kinds of corrosion–wear behaviour were determined in this study. • A linear correlation between total material loss and change in OCP was discovered. • Static CV tests were not useful for predicting dynamic corrosion–wear behaviour

  17. The protective action of two vapour phase inhibitors on the corrosion of mild steel

    Energy Technology Data Exchange (ETDEWEB)

    Bastidas, J.M.; Feliu, S. (Centro Nacional de Investigaciones Metalurgicas, Madrid (Spain)); Mora, E.M. (Universidad Politecnica de Madrid (Spain). Escuela Tecnica Superior de Ingenieros Navales)

    1990-06-01

    The action of two vapour phase inhibitors (VPI), dicyclohexyl-ammonium nitrite (DICHAN) and dicyclohexylamine (DICHAMIN), on the atmospheric corrosion of mild steel at a relative humidity of 100% and under isothermal conditions (25deg C) has been studied. In order to obtain electrochemical data with thin adsorbed moisture layers a vapour phase inhibitor monitor (VPIM) was developed. A check of the data was done by three electrochemical techniques and by the image analysis technique. The tests carried out have revealed that the corrosion rate of mild steel decreases in the presence of DICHAN and DICHAMIN. With the VPIM and the electrochemical techniques used it is possible to understand the inhibition mechanism of these two vapour inhibitors on the atmospheric corrosion of steel. (orig.).

  18. Corrosion protection by anaerobiosis.

    Science.gov (United States)

    Volkland, H P; Harms, H; Wanner; Zehnder, A J

    2001-01-01

    Biofilm-forming bacteria can protect mild (unalloyed) steel from corrosion. Mild steel coupons incubated with Rhodoccocus sp. strain C125 and Pseudomonas putida mt2 in an aerobic phosphate-buffered medium containing benzoate as carbon and energy source, underwent a surface reaction leading to the formation of a corrosion-inhibiting vivianite layer [Fe3(PO4)2]. Electrochemical potential (E) measurements allowed us to follow the buildup of the vivianite cover. The presence of sufficient metabolically active bacteria at the steel surface resulted in an E decrease to -510 mV, the potential of free iron, and a continuous release of ferrous iron. Part of the dissolved iron precipitated as vivianite in a compact layer of two to three microns in thickness. This layer prevented corrosion of mild steel for over two weeks, even in a highly corrosive medium. A concentration of 20 mM phosphate in the medium was found to be a prerequisite for the formation of the vivianite layer. PMID:11730124

  19. Study of electrodeposited polypyrrole coatings for the corrosion protection of stainless steel bipolar plates for the PEM fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, M.A. Lucio [CIE-UNAM, Priv. Xochicalco S/N, 62580 Temixco, Morelos (Mexico); Smit, Mascha A. [Unidad de Materiales, Centro de Investigacion Cientifica de Yucatan (CICY), Calle 43 no. 130, col. Chuburna de Hidalgo, 97200 Merida, Yucatan (Mexico)

    2006-07-14

    Polypyrrole coatings were prepared on stainless steel SS304 in order to study the corrosion protection provided by the conductive polymer in a simulated PEM fuel cell environment. The polypyrrole was deposited by electrochemical polymerization with 0.04, 0.07 and 0.14gcm{sup -2} onto SS304 electrodes. Polarization curves, taken after immersion for 1, 3 or 24h in 0.1M sulphuric acid at either room temperature or 60{sup o}C were used as an accelerated test. For short immersion times, it was found that corrosion current densities (at free corrosion potentials), diminished up to 2 orders of magnitude for samples tested at room temperature and up to 4 orders of magnitude for samples tested at 60{sup o}C. Furthermore, at potentials in the range of the PEM fuel cell anode potential, corrosion rates also decreased up to several orders of magnitude. However, these protective properties were lost at longer times of immersion. The addition of DBSA to the polypyrrole coatings did lead to improved corrosion current densities at the free corrosion potential, however due to the loss of passivity of these samples, the corrosion rates in the potential range applicable to PEM fuel cells were either similar to or larger than bare metal. SEM was used to determine the morphology of the coatings and showed that the most homogeneous coating was obtained for 0.07gcm{sup -2} polypyrrole, without the incorporation of DBSA. (author)

  20. The corrosion protection of AISI(TM) 1010 steel by organic and inorganic zinc-rich primers

    Science.gov (United States)

    Danford, M. D.; Mendrek, M. J.

    1995-01-01

    The behavior of zinc-rich primer-coated AISI 1010 steel in 3.5-percent Na-Cl was investigated using electrochemical techniques. The alternating current (ac) method of electrochemical impedance spectroscopy (EIS), in the frequency range of 0.001 to 40,000 Hz, and the direct current (dc) method of polarization resistance (PR), were used to evaluate the characteristics of an organic, epoxy zinc-rich primer and an inorganic, ethyl silicate zinc-rich primer. A dc electromechanical galvanic corrosion test was also used to determine the corrosion current of each zinc-rich primer anode coupled to a 1010 steel cathode. Duration of the EIS/PR and galvanic testing was 21 days and 24 h, respectively. The galvanic test results demonstrated a very high current between the steel cathode and both zinc-rich primer anodes (38.8 and 135.2 microns A/sq cm for the organic and inorganic primers, respectively). The results of corrosion rate determinations demonstrated a much higher corrosion rate of the zinc in the inorganic primer than in the organic primer, due primarily to the higher porosity in the former. EIS equivalent circuit parameters confirmed this conclusion. Based on this investigation, the inorganic zinc-rich primer appears to provide superior galvanic protection and is recommended for additional study for application on solid rocket booster steel hardware.

  1. Effect of zinc phosphate chemical conversion coating on corrosion behaviour of mild steel in alkaline medium: protection of rebars in reinforced concrete

    OpenAIRE

    Florica Simescu and Hassane Idrissi

    2008-01-01

    We outline the ability of zinc phosphate coatings, obtained by chemical conversion, to protect mild steel rebars against localized corrosion, generated by chloride ions in alkaline media. The corrosion resistance of coated steel, in comparison with uncoated rebars and coated and uncoated steel rebars embedded in mortar, were evaluated by open-circuit potential, potentiodynamic polarization, cronoamperometry and electrochemical impedance spectroscopy. The coated surfaces were characterized by ...

  2. An electrochemical study of corrosion protection by primer-topcoat systems on 4130 steel with ac impedance and dc methods

    Science.gov (United States)

    Mendrek, M. J.; Higgins, R. H.; Danford, M. D.

    1988-01-01

    To investigate metal surface corrosion and the breakdown of metal protective coatings, the ac impedance method is applied to six systems of primer coated and primer topcoated 4130 steel. Two primers were used: a zinc-rich epoxy primer and a red lead oxide epoxy primer. The epoxy-polyamine topcoat was used in four of the systems. The EG and G-PARC Model 368 ac impedance measurement system, along with dc measurements with the same system using the polarization resistance method, were used to monitor changing properties of coated 4230 steel disks immersed in 3.5 percent NaCl solutions buffered at pH 5.4 over periods of 40 to 60 days. The corrosion system can be represented by an electronic analog called an equivalent circuit consisting of resistors and capacitors in specific arrangements. This equivalent circuit parallels the impedance behavior of the corrosion system during a frequency scan. Values for the resistors and capacitors, that can be assigned in the equivalent circuit following a least-squares analysis of the data, describe changes that occur on the corroding metal surface and in the protective coatings. Two equivalent circuits have been determined that predict the correct Bode phase and magnitude of the experimental sample at different immersion times. The dc corrosion current density data are related to equivalent circuit element parameters. Methods for determining corrosion rate with ac impedance parameters are verified by the dc method.

  3. In-situ AFM and EIS study of a solventborne alkyd coating with nanoclay for corrosion protection of carbon steel

    OpenAIRE

    Jing, Li; Ecco, Luiz; Fedel, Michele; Ermini, Valentina; Delmas, Gregory; Pan, Jinshan

    2015-01-01

    A solventborne alkyd composite coating containing modified montmorillonite (MMT) nanoclay was made on carbon steel, and its corrosion protection was investigated by in-situ atomic force microscopy (AFM) and electrochemical impedance spectroscopy (EIS) measurements in 3 wt.% NaCl solution. X-ray diffraction (XRD) analysis indicated intercalation of the MMT sheets in the composite coating. Thermo-gravimetric analysis (TGA) demonstrated improved thermal stability of the composite coating due to ...

  4. Corrosion resistant steel

    International Nuclear Information System (INIS)

    Corrosion-resistant chromium-nickel steel containing cerium and vanadium additions is developed. It is aimed at producing welding structures operating at cryogenic temperatures. The above steel also contains C, Mo, Co, Ca, Y, Fe. Ce and V additions permit to increase the impact strength of joints at the temperature of -253 deg and resistance to the formation of welded cracks by way of grain size refinement of the initial coarse-grained structure and decreasing steel tendency to grain growth during welding heatings. A considerable economic effect from the introduction of the suggested steel is supposed

  5. Electrochemical synthesis of bilayer coatings of poly(N-methylaniline) and polypyrrole on mild steel and their corrosion protection performances

    Energy Technology Data Exchange (ETDEWEB)

    Zeybek, Buelent [Ankara University, Faculty of Science, Department of Chemistry, Ankara (Turkey); Dumlupinar University, Faculty of Arts and Sciences, Department of Chemistry, Kuetahya (Turkey); Ozcicek Pekmez, Nuran, E-mail: npekmez@hacettepe.edu.t [Hacettepe University, Faculty of Science, Department of Chemistry, Ankara (Turkey); Kilic, Esma [Ankara University, Faculty of Science, Department of Chemistry, Ankara (Turkey)

    2011-10-30

    Highlights: > The bilayers of poly(N-methylaniline) and polypyrrole-dodecylsulfate were synthesized. > These films on mild steel were characterized by cyclic voltammetry, FTIR and FESEM. > DS dopant allows permeation to cations and decreases the ingress of chloride ions. > The PNMA/PPy-DS bilayer coating exhibited the best corrosion resistance in 0.5 M HCl. > The protective properties of polymers was developed by preparing their bilayer coatings. - Abstract: Homopolymer and bilayer coatings of poly(N-methylaniline) (PNMA) and polypyrrole-dodecylsulfate (PPy-DS) have been electropolymerized on a mild steel (MS) surface by the potentiodynamic method in aqueous oxalic acid solutions. In order to include dodecylsulfate ion as dopant in the polypyrrole, sodium dodecylsulfate was also added to the polymerization solution of pyrrole. Characterization of coatings was carried out by the cyclic voltammetry, Fourier transform infrared (FTIR) spectroscopy and field emission scanning electron microscopy (FESEM). Corrosion behavior of the polymer coated MS electrodes was investigated in highly aggressive 0.5 M HCl solution by the Tafel test and electrochemical impedance spectroscopy (EIS) techniques. Corrosion test revealed that among the protective coatings obtained, the PNMA/PPy-DS bilayer exhibited the best corrosion resistance at all immersion times.

  6. Protection of type 316 austenitic stainless steel from intergranular stress corrosion cracking by thermo-mechanical treatment

    International Nuclear Information System (INIS)

    Thermomechanical treatment that causes carbide stabilizing aging of cold worked material followed by recrystallization heating made standard stainless steels highly resistant to intergranular corrosion and stress corrosion cracking in different test environments. After a typical thermal history of simulated welding, several IGSCC susceptibility tests were made. The results showed that the treatment was successful in type 316 steel in wide range of conditions, while type 304 was protected only to a small extent even by closely controlled treatment. Response of the materials to the sensitizing heating in terms of impurity segregation at grain boundaries was also examined by means of microchemical analysis. Advantage of method is that no special care is required in selecting heats of material, so that conventional type 316 is usable by improving the mechanical properties substantially through the treatment. In some optimized cases the mechanical property improvement was typically recognized by the yield strength by about 20% higher at room temperature, compared with the material mill annealed. (author)

  7. Corrosion of steel in concrete

    International Nuclear Information System (INIS)

    A comparative study has been made of those properties of Massiv and Standard cements which are considered to determine their ability to protect steel reinforcement from corroding. Saturated Massiv cement has a higher evaporabel water content, but a significantly finer pore structure than has saturated Standard cement. This fine structure resulted in an electrical resistivity ten times higher and chloride diffusivity ten times lower than those of Standard cement. Electrochemical measurements have shown that the passive current density of steel in Massiv mortar is higher than that of steel in Standard mortar, but the higher current should lead to a more rapid decrease in potential to a level at which neither chloride attack of hydrogen evolution will occur. Whereas steel in Standard mortar was found to be highly susceptible to crevice corrosion, no such attack has been observed in Massiv mortar. Moreover, the initiation of chloride induced corrosion and the subsequent rates of corrosion were both lower in Massiv mortar than in Standard mortar. Thus, it may be predicted that Massiv cement would provide greater protection for steel reinforcement in underground structures exposed to chloride containing ground water than would Standard cement. (author)

  8. Protection of carbon steel against hot corrosion using thermal spray Si- and Cr-base coatings

    Science.gov (United States)

    Porcayo-Calderon, J.; Gonzalez-Rodriguez, J. G.; Martinez, L.

    1998-02-01

    A Fe75Si thermal spray coating was applied on the surface of a plain carbon steel baffle plate. Beneath this coating, a Ni20Cr coating was applied to give better adherence to the silicon coating. The baffle was installed in the high-temperature, fireside, corrosion zone of a steam generator. At the same time, an uncoated 304 stainless steel baffle was installed nearby for comparison. For 13 months the boiler burned heavy fuel oil with high contents of vanadium. The samples were studied employing scanning electron microscopy, x-ray microanalysis, and x-ray diffraction techniques. After that, it was possible to inspect the structural state of the components, and it was found that the stainless steel baffle plates were destroyed almost completely by corrosion, whereas the carbon steel coated baffle plate did not suffer a significant attack, showing that the performance of the thermal spray coating was outstanding and that the coating was not attacked by vanadium salts of the molten slag.

  9. Corrosion protection of the reinforcing steels in chloride-laden concrete environment through epoxy/polyaniline–camphorsulfonate nanocomposite coating

    International Nuclear Information System (INIS)

    Highlights: • Epoxy/polyaniline–camphorsulfonate nanocomposite coating well protects steel rebar. • Coating performance is evaluated by impedance measurements up to 1 year. • Ultimate bond strength between the coated rebars and concrete is measured. • Self-compacting concrete shows better anticorrosive property compared to normal one. - Abstract: In this study, an epoxy/polyaniline–camphorsulfonate nanocomposite (epoxy/PANI–CSA) is employed to protect reinforcing steels in chloride-laden concrete environment. The synthesized nanocomposite was characterized using Fourier transform infrared spectroscopy and transmission electron microscopy. Bare, epoxy-coated and epoxy/PANI–CSA nanocomposite-coated steel rebars were embedded in normal and self-compacting concretes. To evaluate their corrosion behaviors, open circuit potential and impedance measurements were performed for the duration of 1 year. Ultimate bond strength of concrete with the reinforcement bars were measured in corroded and uncorroded conditions. It was found that epoxy/PANI–CSA coating provides good corrosion resistance and durable bond strength with concrete for steel rebars

  10. Composition and Morphology of Product Layers in the Steel/Cement Paste Interface in Conditions of Corrosion and Cathodic Protection in Reinforced Concrete :

    OpenAIRE

    Koleva, D. A.; Breugel, K., van; Wit, J.H.W. de; Fraaij, A.L.A.; Boshkov, N.

    2007-01-01

    The present study explores the formation of corrosion products on the steel surface in reinforced concrete in conditions of corrosion and subsequent transformation of these layers in conditions of cathodic protection (CP). Of particular interest was to investigate if the introduced pulse CP (as cost- effective alternative of CP) will lead to similar (or even better) transformation of the product layers on the steel surface, compared to conventional techniques. Qualification and quantification...

  11. Preparation of crosslinked amphiphilic silver nanogel as thin film corrosion protective layer for steel.

    Science.gov (United States)

    Atta, Ayman M; El-Mahdy, Gamal A; Al-Lohedan, Hamad A; Ezzat, Abdelrahman O

    2014-01-01

    Monodisperse silver nanoparticles were synthesized by a new developed method via reaction of AgNO3 and oleic acid with the addition of a trace amount of Fe3+ ions. Emulsion polymerization at room temperature was employed to prepare a core-shell silver nanoparticle with controllable particle size. N,N'-methylenebisacrylamide (MBA) and potassium peroxydisulfate (KPS) were used as a crosslinker, and as redox initiator system, respectively for crosslinking polymerization. The structure and morphology of the silver nanogels were characterized by Fourier transform infrared spectroscopy (FTIR), transmission and scanning electron microscopy (TEM and SEM). The effectiveness of the synthesized compounds as corrosion inhibitors for steel in 1 M HCl was investigated by various electrochemical techniques such as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Monolayers of silver nanoparticle were self-assembled on the fresh active surface of the steel electrode and have been tested as a corrosion inhibitor for steel in 1 M HCl solution. The results of polarization measurements showed that nanogel particles act as a mixed type inhibitor. PMID:25036152

  12. Preparation of Crosslinked Amphiphilic Silver Nanogel as Thin Film Corrosion Protective Layer for Steel

    Directory of Open Access Journals (Sweden)

    Ayman M. Atta

    2014-07-01

    Full Text Available Monodisperse silver nanoparticles were synthesized by a new developed method via reaction of AgNO3 and oleic acid with the addition of a trace amount of Fe3+ ions. Emulsion polymerization at room temperature was employed to prepare a core-shell silver nanoparticle with controllable particle size. N,N'-methylenebisacrylamide (MBA and potassium peroxydisulfate (KPS were used as a crosslinker, and as redox initiator system, respectively for crosslinking polymerization. The structure and morphology of the silver nanogels were characterized by Fourier transform infrared spectroscopy (FTIR, transmission and scanning electron microscopy (TEM and SEM. The effectiveness of the synthesized compounds as corrosion inhibitors for steel in 1 M HCl was investigated by various electrochemical techniques such as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS. Monolayers of silver nanoparticle were self-assembled on the fresh active surface of the steel electrode and have been tested as a corrosion inhibitor for steel in 1 M HCl solution. The results of polarization measurements showed that nanogel particles act as a mixed type inhibitor.

  13. Incorporation of Fe3O4/CNTs nanocomposite in an epoxy coating for corrosion protection of carbon steel

    International Nuclear Information System (INIS)

    In this study Fe3O4/CNTs composite with magnetic property was prepared by attaching magnetic nanoparticles (Fe3O4) to carbon nanotubes (CNTs) by hydrothermal method. The obtained Fe3O4/CNTs composite was characterized by Fourier transform infrared (FTIR) spectroscopy, powder x-ray diffraction and transmission electron microscopy. The Fe3O4/CNTs composite was then incorporated into an epoxy coating at concentration of 3 wt%. Corrosion protection of epoxy coating containing Fe3O4/CNTs composite was evaluated by electrochemical impedance spectroscopy and adhesion measurement. The impedance measurements show that Fe3O4/CNTs composite enhanced the corrosion protection of epoxy coating. The corrosion resistance of the carbon steel coated by epoxy coating containing Fe3O4/CNTs composite was significantly higher than that of carbon steel coated by clear epoxy coating and epoxy coating containing CNTs. FE-SEM photographs of fracture surface of coatings showed good dispersion of Fe3O4/CNTs composite in the epoxy matrix. (paper)

  14. Incorporation of Fe3O4/CNTs nanocomposite in an epoxy coating for corrosion protection of carbon steel

    Science.gov (United States)

    Pham, Gia Vu; Truc Trinh, Anh; To, Thi Xuan Hang; Duong Nguyen, Thuy; Trang Nguyen, Thu; Hoan Nguyen, Xuan

    2014-09-01

    In this study Fe3O4/CNTs composite with magnetic property was prepared by attaching magnetic nanoparticles (Fe3O4) to carbon nanotubes (CNTs) by hydrothermal method. The obtained Fe3O4/CNTs composite was characterized by Fourier transform infrared (FTIR) spectroscopy, powder x-ray diffraction and transmission electron microscopy. The Fe3O4/CNTs composite was then incorporated into an epoxy coating at concentration of 3 wt%. Corrosion protection of epoxy coating containing Fe3O4/CNTs composite was evaluated by electrochemical impedance spectroscopy and adhesion measurement. The impedance measurements show that Fe3O4/CNTs composite enhanced the corrosion protection of epoxy coating. The corrosion resistance of the carbon steel coated by epoxy coating containing Fe3O4/CNTs composite was significantly higher than that of carbon steel coated by clear epoxy coating and epoxy coating containing CNTs. FE-SEM photographs of fracture surface of coatings showed good dispersion of Fe3O4/CNTs composite in the epoxy matrix.

  15. Multilayer graphene for long-term corrosion protection of stainless steel bipolar plates for polymer electrolyte membrane fuel cell

    DEFF Research Database (Denmark)

    Stoot, Adam Carsten; Camilli, Luca

    2015-01-01

    Abstract Motivated by similar investigations recently published (Pu et al., 2015), we report a comparative corrosion study of three sets of samples relevant as bipolar plates for polymer electrolyte fuel cells: stainless steel, stainless steel with a nickel seed layer (Ni/SS) and stainless steel with Ni seed layer coated by a multi-layered graphene thin film (G/Ni/SS). The graphene film, synthesized by chemical vapour deposition (CVD), has a moderate amount of defects according to Raman spectroscopy. Short/medium-term corrosion test shows no significant advantage of using G/Ni/SS rather than Ni/SS, both samples exhibiting a similar trend, thus questioning the short-term positive effect of graphene coatings. However, partial immersion in boiling seawater for three weeks reveals a clear superiority of the graphene coating with respect to steel just protected by Ni. After the test, the graphene film is still intact with unchanged defect density. Our results show that even non-perfect multilayer graphene films can considerably increase the lifetime of future-generation bipolar plates for fuel cells.

  16. In-Situ AFM and EIS Study of Waterborne Acrylic Latex Coatings for Corrosion Protection of Carbon Steel

    OpenAIRE

    LI, Jing; Ecco, Luiz; Delmas, Gregory; Whitehouse, Nigel; Collins, Peter; Deflorian, Flavio; Pan, Jinshan

    2015-01-01

    Corrosion protection for carbon steel by three waterborne styrene-acrylic latex coatings with different glass transition temperature (Tg) and levels of hydrophobicity has been studied by in-situ atomic force microscope (AFM) and electrochemical impedance spectroscopy (EIS) measurements in 3.0 wt% NaCl solution. The AFM images reveal the micro-and nano-structure of and pinholes in the coatings as well as their changes during exposure in the solution, whereas the EIS spectra vs. time of exposur...

  17. Galvanic Liquid Applied Coating System For Protection of Embedded Steel Surfaces from Corrosion

    Science.gov (United States)

    Curran, Joseph; Curran, Jerome; Voska, N. (Technical Monitor)

    2002-01-01

    Corrosion of reinforcing steel in concrete is an insidious problem facing Kennedy Space Center (KSC), other Government Agencies, and the general public. These problems include KSC launch support structures, highway bridge infrastructure, and building structures such as condominium balconies. Due to these problems, the development of a Galvanic Liquid Applied Coating System would be a breakthrough technology having great commercial value for the following industries: Transportation, Infrastructure, Marine Infrastructure, Civil Engineering, and the Construction Industry. This sacrificial coating system consists of a paint matrix that may include metallic components, conducting agents, and moisture attractors. Similar systems have been used in the past with varying degrees of success. These systems have no proven history of effectiveness over the long term. In addition, these types of systems have had limited success overcoming the initial resistance between the concrete/coating interface. The coating developed at KSC incorporates methods proven to overcome the barriers that previous systems could not achieve. Successful development and continued optimization of this breakthrough system would produce great interest in NASA/KSC for corrosion engineering technology and problem solutions. Commercial patents on this technology would enhance KSC's ability to attract industry partners for similar corrosion control applications.

  18. Nanocomposite films for corrosion protection

    OpenAIRE

    Sababi, Majid

    2013-01-01

    This thesis describes technical and scientific aspects of new types of composite films/coatings for corrosion protection of carbon steel, composite films with nanometer thickness consisting of mussel adhesive protein (Mefp?1) and ceria nanoparticles, and polymeric composite coatings with micrometre thickness consisting of conducting polymer and ceria nanoparticles in a UV?curing polyester acrylate (PEA) resin. The influence of microstructure on corrosion behaviour was studied for a Fe?Cr?V?N ...

  19. Corrosion of metallic materials. Dry corrosion, aqueous corrosion and corrosion by liquid metal, methods of protection

    International Nuclear Information System (INIS)

    This book is based on a course on materials given in an engineering school. The author first gives an overview of metallurgy issues: metallic materials (pure metals, metallic alloys), defects of crystal lattices (point defects, linear defects or dislocations), equilibrium diagrams, steels and cast, thermal processing of steels, stainless steels, aluminium and its alloys, copper and its alloys. The second part addresses the properties and characterization of surfaces and interfaces: singularity of a metal surface, surface energy of a metal, energy of grain boundaries, adsorption at a material surface, metal-electrolyte interface, surface oxide-electrolyte interface, techniques of surface analysis. The third chapter addresses the electrochemical aspects of corrosion: description of the corrosion phenomenon, free enthalpy of a compound and free enthalpy of a reaction, case of dry corrosion (thermodynamic aspect, Ellingham diagram, oxidation mechanisms, experimental study, macroscopic modelling), case of aqueous corrosion (electrochemical thermodynamics and kinetics, experimental determination of corrosion rate). The fourth part addresses the different forms of aqueous corrosion: generalized corrosion (atmospheric corrosion, mechanisms and tests), localized corrosion (galvanic, pitting, cracking, intergranular, erosion and cavitation), particular cases of stress cracking (stress corrosion, fatigue-corrosion, embrittlement by hydrogen), and bi-corrosion (of non alloyed steels, of stainless steels, and of aluminium and copper alloys). The sixth chapter addresses the struggle and the protection against aqueous corrosion: methods of prevention, scope of use of main alloys, geometry-based protection of pieces, use of corrosion inhibitors, use of organic or metallic coatings, electrochemical protection. The last chapter proposes an overview of corrosion types in industrial practices: in the automotive industry, in the oil industry, in the aircraft industry, and in the electronuclear industry

  20. Failure mechanism of thin Al2O3 coatings grown by atomic layer deposition for corrosion protection of carbon steel

    International Nuclear Information System (INIS)

    Combined analysis by electrochemical impedance spectroscopy (EIS), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and field emission scanning electron microscopy (FESEM) of the corrosion protection provided to carbon steel by thin (50 nm) Al2O3 coatings grown by atomic layer deposition (ALD) and its failure mechanism is reported. In spite of excellent sealing properties, the results show an average dissolution rate of the alumina coating of ?7 nm h-1 in neutral 0.2 M NaCl and increasing porosity of the remaining layers with increasing immersion time. Alumina dissolution is triggered by the penetration of the solution via cracks/pinholes through the coating to the substrate surface where oxygen reduction takes place, raising the pH. At defective substrate surface sites of high aspect ratio and concentrated residual mechanical stress (along scratches) presumably exposing a higher steel surface fraction, localized dissolution of the coating is promoted by a more facile access of the solution to the substrate surface enhancing oxygen reduction. De-adhesion of the coating is also promoted in these sites by the ingress of the anodic dissolution trenching the steel surface. Localized corrosion of the alloy (i.e. pitting) is triggered prior to complete dissolution of the alumina film on the elsewhere still coated surface matrix.

  1. Aminophosphonate corrosion inhibitors for steel

    International Nuclear Information System (INIS)

    The protective properties of the aminophosphonate acids and their complexes with the magnesium and calcium cations in the soft water relative to the rotating steel cylinder are studied. Only two of the seven studied acids, namely the 1.1-oxycarboxypropane-3-amino-di(methylene-phosphonate) and hexamethylenediamine-N,N-tetra (methylenephosphonate acids - are able completely to suppress the steel corrosion in the water. As a rule the complexonates of the studied acids proved to be more efficient, whereby the stability constants by the similar complexing agent (Cs) are the determining factor. The dependence of the protective concentration on the Cs for the Mg2+ and Ca2+ phosphonates, usually less stable as the analogous iron complexonates has the maximum, whereby the complexonates of those acids are more effective, wherein the inherent protective properties are weaker

  2. Corrosion protection of 316 L stainless steel by a TiO2 nanoparticle coating prepared by sol-gel method

    International Nuclear Information System (INIS)

    A uniform and TiO2 nanoparticle coating on steels has been prepared using sol-gel method and hydrothermal post-treatments. The morphology and structure of the coatings were analysed using atomic force microscopy and X-ray diffraction. The anticorrosion performances of the coatings in dark and under ultraviolet illumination have been evaluated by using electrochemical techniques. The influences of coating thickness, pH and NaCl concentration on corrosion protection have been examined as well. The results indicate that the TiO2 nanoparticle coatings on steels exhibit an excellent corrosion resistance due to a ceramic protective barrier on metal surface in dark, and a photo-generated cathodic protection current under UV illumination. The electrochemical impedance spectroscopy measurements provide an explanation to the increased resistance of nano TiO2 particles coated 316 L stainless steel against corrosion

  3. Effect of zinc phosphate chemical conversion coating on corrosion behaviour of mild steel in alkaline medium: protection of rebars in reinforced concrete

    Directory of Open Access Journals (Sweden)

    Florica Simescu and Hassane Idrissi

    2008-01-01

    Full Text Available We outline the ability of zinc phosphate coatings, obtained by chemical conversion, to protect mild steel rebars against localized corrosion, generated by chloride ions in alkaline media. The corrosion resistance of coated steel, in comparison with uncoated rebars and coated and uncoated steel rebars embedded in mortar, were evaluated by open-circuit potential, potentiodynamic polarization, cronoamperometry and electrochemical impedance spectroscopy. The coated surfaces were characterized by x-ray diffraction and scanning electron microscopy. First, coated mild steel rebars were studied in an alkaline solution with and without chloride simulating a concrete pore solution. The results showed that the slow dissolution of the coating generates hydroxyapatite Ca10(PO46(OH2. After a long immersion, the coating became dense and provided an effective corrosion resistance compared with the mild steel rebar. Secondly, the coated and uncoated steel rebars embedded in mortar and immersed in chloride solution showed no corrosion or deterioration of the coated steel. Corrosion rate is considerably lowered by this phosphate coating.

  4. Effect of zinc phosphate chemical conversion coating on corrosion behaviour of mild steel in alkaline medium: protection of rebars in reinforced concrete

    International Nuclear Information System (INIS)

    We outline the ability of zinc phosphate coatings, obtained by chemical conversion, to protect mild steel rebars against localized corrosion, generated by chloride ions in alkaline media. The corrosion resistance of coated steel, in comparison with uncoated rebars and coated and uncoated steel rebars embedded in mortar, were evaluated by open-circuit potential, potentiodynamic polarization, cronoamperometry and electrochemical impedance spectroscopy. The coated surfaces were characterized by x-ray diffraction and scanning electron microscopy. First, coated mild steel rebars were studied in an alkaline solution with and without chloride simulating a concrete pore solution. The results showed that the slow dissolution of the coating generates hydroxyapatite Ca10(PO4)6(OH)2. After a long immersion, the coating became dense and provided an effective corrosion resistance compared with the mild steel rebar. Secondly, the coated and uncoated steel rebars embedded in mortar and immersed in chloride solution showed no corrosion or deterioration of the coated steel. Corrosion rate is considerably lowered by this phosphate coating.

  5. Adsorption rate and protective effect of tributyl(cyclohexyl)ammonium chloride inhibitor on the acidic corrosion of steel

    Energy Technology Data Exchange (ETDEWEB)

    Magerramov, A.M.; Aliyev, I.A.; Khalilova, F.I. [Faculty of Chemistry, Baku State University (Azerbaijan); Rzayev, Z.M.O. [Chemical Engineering Department, Faculty of Engineering, Hacettepe University, Beytepe, Ankara (Turkey)

    2010-08-15

    The inhibition of corrosion of a steel surface by an inhibitor, tributyl(cyclohexyl)ammonium chloride (TBCA), was investigated by gravimetric and electrochemical polarization measurements in various aqueous solutions of HCl and H{sub 2}SO{sub 4} acids. It is known that the most extensive corrosive destruction proceeds during the initial stage of contact between the metallic surface and the aggressive surroundings. The change from H{sub 2}SO{sub 4} to HCl considerably decreases the time for formation of an adsorption layer. The high adsorption of the surface-active cationic TBCA on the steel electrode surface can be explained by the specific adsorption of Cl{sup -} anions increasing the negative charge on the electrode surface. It was observed that the value of the polarizing current can be increased from time to time by addition of more TBCA inhibitor. This fact can be explained by the low stability of the film-forming layer on the steel. A similar decrease of the protective effect was also observed in HCl solution. The inhibitor provides at least a slowing of the corrosion process ({tau}=21 min). It was found that an increase in H{sub 2}SO{sub 4} concentration from 1.0 to 0.2 N did not change the protective action of the inhibitor and had rather high values ({theta}=283 ma/h, {psi}=84%, and {tau}=14 min at [I]=3.5 x 10{sup -4} mol/L). It was shown that the attraction constant has a negative value (A=-1.5 and K{sub a}=22.3) for the inhibitor, which relates to a high value for the adsorption ability of TBCA in HCl solution and therefore with the intermolecular repulsive force between adsorption molecules having similar charges. The protective action of TBCA increases with an increase in temperature, which is correlated with the chemical nature of its adsorption on the steel surface. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  6. Corrosion of steel in concrete

    OpenAIRE

    Tuutti, Kyösti

    1982-01-01

    The research work that is presented in this thesis aims at mapping out the various mechanisms which control the process of steel corrosion in concrete. The process of corrosion is illustrated with a schematic model where the service life is divided into a period of initiation and a period of propagation. The time up to the initiation of the corrosion process is determined by the flow of penetrating substances into the concrete cover and by the threshold concentration for corrosion to start. T...

  7. New sol-gel formulations to increase the barrier effect of a protective coating against the corrosion of steels

    OpenAIRE

    Certhoux, Elise; Ansart, Florence; Turq, Viviane; Bonino, Jean-Pierre; Sobrino, Jean-Michel; Garcia, Julien; Reby, Jean

    2013-01-01

    Films were deposited onto AISI 430 stainless steel substrates by dip-coating technique. The aim is to reach the AISI 304L stainless steel anti-corrosion properties by a coated AISI 430 stainless steel system. Sol formulation is done from the starting precursors tetraethylorthosilicate (TEOS) and 3(trimethoxysilyl) propyl methacrylate (MAP). After the hydrolysis of these precursors, sol-gel reactions occur before the addition (or not) of a controlled quantity of cerium nitrate. The addition of...

  8. Corrosion protection of steel by thin coatings of starch-oil dry lubricants

    Science.gov (United States)

    Corrosion of materials is one of the most serious and challenging problems faced worldwide by industry. Dry lubricants reduce friction between two metal surfaces. This research investigated the inhibition of corrosive behavior a dry lubricant formulation consisting of jet-cooked corn starch and soyb...

  9. Electrodeposition of polyaniline, poly(2-iodoaniline), and poly(aniline- co-2-iodoaniline) on steel surfaces and corrosion protection of steel

    Science.gov (United States)

    Bereket, Gözen; Hür, Evrim; ?ahin, Yücel

    2005-12-01

    Polyaniline (PANi), poly(2-iodoaniline) (PIANi), and poly(aniline- co-2-iodoaniline) ( co-PIANi) were synthesized using cyclic voltammetry in acetonitrile solution containing tetrabuthylammonium perchlorate (TBAP) and perchloric acid (HClO 4) on 304-stainless steel electrodes. Adherent and black polymer films were obtained on the electrodes. The structure and properties of these polymer films were characterized by FTIR and UV-vis spectroscopy and electrochemical method. The corrosion performance of PANi, PIANi, and co-PIANi coated electrodes were investigated in 0.5 M hydrochloric acid (HCl) solutions by potentiodynamic polarization technique, open circuit potential-time curves and electrochemical impedance spectroscopy, EIS. It was found that the PANi film could provide much better protection than PIANi, and co-PIANi and PANi films have barrier property as well as acting as passivator. On the other hand PIANi and co-PIANi films are acting as barrier coatings which were related with the prevention of cathodic reaction taking place at metalelectrolyte interface. EIS measurement shows that every coating gives protection efficiency of greater than 75% after 48 h of immersion time in corrosive test solution.

  10. Acid Corrosion Inhibition of Steel by Lamotrigine

    OpenAIRE

    Nataraja, S. E.; B. M. Praveen; Venkatesha, T. V.; Shylesha, B. S.

    2012-01-01

    Corrosion inhibition effect of lamotrigine on steel in 1.0?M?HCl and 0.5?M?H2SO4 was studied by techniques like weight loss, polarisation, and electrochemical impedance spectroscopy. Results indicated that lamotrigine is more competent in HCl than in H2SO4 and is justified by scanning electron micrographs. Protection efficiency increased with the concentration of inhibitor and decreased with temperature. Adsorption study revealed the comprehensive adsorption of lamotrigine molecules on steel ...

  11. Layered double hydroxides as containers of inhibitors in organic coatings for corrosion protection of carbon steel

    OpenAIRE

    Hang, To Thi Xuan; Truc, Trinh Anh; Duong, Nguyen Thuy; Pébère, Nadine; Olivier, Marie-Georges

    2012-01-01

    The present work focuses on the use of layered double hydroxides (LDH) as containers for corrosion inhibitors in an epoxy coating. 2-Benzothiazolylthio-succinic acid (BTSA), used as corrosion inhibitor, was intercalated by co-precipitation in magnesium-aluminum layered double hydroxides. The obtained LDH-BTSA was characterized by infrared spectroscopy, X-ray diffraction and scanning electron microscopy. BTSA release from LDH-BTSA in NaCl solutions was investigated by UV-vis spectroscopy. The ...

  12. Effective corrosion protection

    International Nuclear Information System (INIS)

    The following methods have been developed to minimize corrosion in conventional and nuclear power plants, heating station equipment, and other heat generating installations and district heat distribution grids: (1) chemical cleaning of steam and water boilers by using a special active agent which forms compounds with multivalent metal ions and dissolves already existing deposits on the wall, (2) corrosion protection of steam and hot water boilers of all systems and types during shut down by the use of a film-forming substance, and (3) corrosion protection of warm and hot water grids during operation or shut down by introducing a corrosion inhibitor which forms a protective film on all metal surfaces upon which the warm or hot water impinges during routine operation. The technical and economical advantages of the methods are summarized

  13. Corrosion of Steel in Concrete, Part I – Mechanisms

    DEFF Research Database (Denmark)

    Küter, André; Møller, Per; Geiker, Mette Rica

    2006-01-01

    prematurely. Reinforcement corrosion is identified to be the foremost cause of deterioration. Steel in concrete is normally protected by a passive layer due the high alkalinity of the concrete pore solution; corrosion is initiated by neutralization through atmospheric carbon dioxide and by ingress of...... depassivation ions, especially chloride ions. The background and consequences of deterioration of reinforced concrete structures caused by steel corrosion are summarized. Selected corrosion mechanisms postulated in the literature are briefly discussed and related to observations. The key factors controlling...... initiation and propagation of corrosion of steel in concrete are outlined....

  14. Development of Nb2O5|Cu composite as AISI 1020 steel thermal spray coating for protection against corrosion by soil in buried structures

    International Nuclear Information System (INIS)

    An Nb2O|Cu corrosion-resistant coating was developed and applied onto AISI 1020 steel substrate by Powder Flame Spray. A galvanostatic electrochemical technique was employed, with and without ohmic drop, in four different soils (two corrosively aggressive and two less aggressive). Behavior of coatings in different soils was compared using a cathodic hydrogen reduction reaction (equilibrium potential, overvoltage and exchange current density) focusing on the effect of ohmic drop. Results allow recommendation of Nb2O5|Cu composite for use in buried structure protection. (author)

  15. Evaluation of the protection behaviour of reinforcement steel against corrosion induced by chlorides in reinforced mortar specimens; Avaliacao do comportamento frente a corrosao pelo ataque de cloreto de argamassa armada apos varios tratamentos protetores

    Energy Technology Data Exchange (ETDEWEB)

    Crivelaro, Marcos

    2002-07-01

    In this work various treatments for protecting reinforcing steels against corrosion induced by chlorides have been evaluated. Additives to mortars and surface treatments given to reinforcing steels were evaluated as corrosion protection measures. In the preliminary tests the corrosion resistance of a CA 50 steel treated by immersion in nearly 50 different solutions, was determined. The solutions were prepared with tannins (from various sources) and/or benzotriazole, and during immersion, a surface film formed on the steel. The corrosion resistance of the coated steels was evaluated in a saturated Ca(OH){sub 2} solution with 5% (wt) NaCl. Preliminary tests were also carried out with mortars reinforced with uncoated steel to which tannin or lignin was added. Two organic coatings, a monocomponent and a bicomponent type, formulated specially for this investigation, with both tannin and benzotriazole, were also tested in the preliminary tests to select the coating with better corrosion protection property. The bicomponent type (epoxy coating) showed better performance than the monocomponent type coating, and the former was therefore chosen to investigate the corrosion performance on CA 50 steel inside mortar specimens. From the preliminary tests, two solutions with tannin from two sources, Black Wattle (Acacia mearnsii) and Brazilian tea (Ilex paraguariensis St. Hill), to which benzotriazole and phosphoric acid were added, were chosen. Mortar specimens reinforced with CA50 steel treated by immersion in these two solutions were prepared. Also, epoxy coated CA50 steel was tested as reinforcement inside mortar specimens. Mortars reinforced with uncoated CA50 steel were also prepared and corrosion tested for comparison. The effect of tannin and lignin as separate additives to the mortar on the corrosion resistance of uncoated steel was also studied. The reinforced mortar specimens were tested with various cycles of immersion for 2 days in 3.5% (wt) NaCl followed by with air drying for 5 days. The corrosion tests used in this investigation were gravimetric and electrochemical tests. The results showed satisfactory corrosion performance for all kinds of protection measures. However, the performance depended on the type of protection used. The best performance was obtained with tannin containing epoxy coated steel, followed by the steel treated by immersion in tannin containing solutions and finally by the addition of tannin (Black Wattle) or lignin to the mortar. All the protection measures evaluated in this study are economically viable and environmentally friendly and can therefore be considered for protecting reinforcement steels against corrosion. (author)

  16. Corrosion fatigue of steel in concrete structures

    International Nuclear Information System (INIS)

    The basic objective of this research programme was to clarify to what extent the traditional alkaline protection is sufficient also under cyclic actions in chloride environments or under which conditions more protection efforts (coating, cathodic protection) would be required. As a measure of the efficiency of the protection the fatigue strength of the prestressing steel under simultaneous action of different corrosive environments has been investigated. Corrosion fatigue tests on 3 series of 3-point-loaded beams post-tensioned with a 7-wire monostrand tendon according to German standard specifications have been performed. The corrosive environment was produced for the beams of the first two series by wetting their surface with salt water in regular intervals. For the third series of beams chloride has been added to the concrete and the grouting mortar and the beams have been wetted with water at proper intervals. Constant amplitude load cycles have been applied. (orig./MM)

  17. Tantalum oxide nanocoatings prepared by atomic layer and filtered cathodic arc deposition for corrosion protection of steel: Comparative surface and electrochemical analysis

    International Nuclear Information System (INIS)

    Highlights: ? 50 nm Ta2O5 coatings grown by ALD at 160 °C and FCAD for protection of steel. ? Combined analysis by ToF-SIMS, XPS, polarization curves and EIS. ? Relation between chemical architecture and corrosion protection properties studied. ? Localized corrosion by pitting with absence of coating dissolution demonstrated. ? Origin and role of spurious interfacial oxide promoting coating breakdown emphasized. -- Abstract: A comparative study by Time-of-Flight Secondary Ions Mass Spectrometry and X-ray Photoelectron Spectroscopy, i–E polarization curves and Electrochemical Impedance Spectroscopy of the corrosion protection of low alloy steel by 50 nm thick tantalum oxide coatings prepared by low temperature Atomic Layer Deposition (ALD) and Filtered Cathodic Arc Deposition (FCAD) is reported. The data evidence the presence of a spurious oxide layer mostly consisting of iron grown by transient thermal oxidation at the ALD film/substrate interface in the initial stages of deposition and its suppression by pre-treatment in the FCAD process. Carbonaceous contamination (organic and carbidic) resulting from incomplete removal of the organic precursor is the major cause of the poorer sealing properties of the ALD film. No coating dissolution is demonstrated in neutral or acid 0.2 M NaCl solutions. In acid solution localized corrosion by pitting proceeds faster with the ALD than with the FCAD coating. The roles of the pre-existing channel defects exposing the substrate surface and of the spurious interfacial oxide promoting coating breakdown and/or delamination are emphasized

  18. LongerLife products increase the sustainability. Is corrosion protection ecologically useful for steel components?; LongerLife-Produkte erhoehen die Nachhaltigkeit. Ist Korrosionsschutz von Stahlbauteilen oekologisch sinnvoll?

    Energy Technology Data Exchange (ETDEWEB)

    Rogall, Armin Dietmar [Fachhochschule Dortmund (Germany). Fachbereich Architektur

    2011-07-01

    The installation of hot-dip galvanized construction units means sustainable acting. Since corrosion protection by hot-dip galvanizing can be particularly named sustainable due to its longevity, its environmental careful production, its recycling ability and life extension of steel components. Particularly the reduction of the maintenance cycles and utilization costs accompanying with a slightly higher initial investment makes the hot-dip galvanizing a sustainable system. Steel components which are treated with galvanization and colour coating, have a maintenance-free life span of more than 80 years.

  19. Marine corrosion of mild steel at Lumut, Perak

    Science.gov (United States)

    Ting, Ong Shiou; Potty, Narayanan Sambu; Liew, Mohd. Shahir

    2012-09-01

    The corrosion rate of structural steels in the adverse marine and offshore environments affects the economic interest of offshore structures since the loss of steel may have significant impact on structural safety and performance. With more emphasis to maintain existing structures in service for longer time and hence to defer replacement costs, there is increasing interest in predicting corrosion rate at a given location for a given period of exposure once the protection coating or cathodic protection is lost. The immersion depth, salinity, steel composition and water pollution will be taken into account. Various corrosion allowances are prescribed for structural members by different standards. There are no studies to determine the appropriate corrosion allowance for steel structures in marine environment in Malaysia. The objectives of the research are to determine the nature and rate of corrosion in mm/year for steel structures in marine environment. It also tries to identify whether the corrosion rate is affected by differences in the chemical composition of the steels, and microalgae. Two sets of corrosion coupons of Type 3 Steel consisting of mild steel were fabricated and immersed in seawater using steel frames. The corrosion rate of the coupon in mm/ per year is estimated based on the material weight loss with time in service. The results are compared with recommendations of the code.

  20. Corrosion protection of cold-rolled steel with alkyd paint coatings composited with submicron-structure types polypyrrole-modified nano-size alumina and carbon nanotubes

    International Nuclear Information System (INIS)

    Highlights: ? Alumina/carbon nanotube (CNT) supported polypyrrole (PPy) particles were prepared. ? Various paint compositions with alkyd binder were immersion tested. ? Alumina-supported PPy based coating provided steel protection in NaCl solution. ? Polyelectrolyte modified CNT embedded coating afforded long-term stable protection. ? sulphonated CNT loaded coating indicated firm corrosion resistance in HCL solution. ? Results are interpreted on the basis of nano and microstructure of the particles. - Abstract: This paper is focused on studying corrosion protection of cold-rolled steel with alkyd paint coatings comprising nano-size alumina and either polystyrene-sulphonate (PSS) modified or sulphonated multi-walled carbon nanotube (MWCNT) supported polypyrrole (PPy). Single layer coatings (in thickness of 40 ± 5 ?m) comprising PPy deposited alumina and PSS modified MWCNT supported PPy afforded viable protection during the 1 M sodium chloride test. The coatings containing PSS modified and weakly sulphonated MWCNTs (at volume fractions of 9.9 × 10?4 and 2.5 × 10?4) with PPy volume fractions of 3.5 × 10?3 and 2.5 × 10?3 provided effective corrosion prevention during the 1 M sodium chloride and hydrochloric acid solution tests. While inhibitor particles were characterised by infrared spectroscopy, corrosion products formed at the paint–steel interface were studied by X-ray photoelectron spectroscopy. Apart from the electron microscopy observations, rheology study of three-dimensional structure of the inhibitor particles was performed in dispersions at similar compositions to those used for the paint formulations. Thus, protection mechanism relating to both types of immersion tests is discussed in terms of properties of the inhibitor particles and their microstructure in the coatings.

  1. Protection of Mild Steel Against Sulphides Corrosion In Petroleum Oil Industry

    International Nuclear Information System (INIS)

    The aggressive properties of the media encountered when drilling for oil derive from the fact that they contain an abundance of mineralized water, as well as hydrogen sulphide and carbon dioxide. Particularly vulnerable to corrosion and installation of old deposits, where highly mineralized water or sometimes even sea water, is pumped into the bed so as to increase the oil yield, and where acid treatment is also carried out, the injection of such water into the bed creates favourable conditions for the development of microbiological processes promoting the life activity of sulphate-reducing bacteria and contributing to the appearance of hydrogen sulphide in the system

  2. Alumina nanostructured coating for corrosion protection of 316L stainless steel

    OpenAIRE

    P. Doodman; M. A. Faghihi-Sani; N. Barati; Afshar, A.

    2014-01-01

    Nanostructured alumina thin films were coated on stainless steel by Sol-Gel dip coating method. In order to prevent crack formation, Al2O3 films were kept in a solvent bath immediately after coating to reduce the rate of drying. Effects of calcination temperature and withdrawal speed on structural properties were analyzed using XRD and SEM. Topography and thickness of coatings were analyzed by AFM. Effects of the above parameters on anticorrosion performance of coats have been evaluated throu...

  3. Corrosion fatigue of steels

    International Nuclear Information System (INIS)

    Corrosion fatigue phenomena can be classified into two main groups according to the electrochemical state of the metal surface in the presence of electrolytes: the active and the passive state with an important sub-group of corrosion fatigue in the unstable passive state. The allowable stress for structures exposed to the conjoint action of corrosion and fatigue is influenced by many factors: kind of media, number of cycles, frequency, mean stress, size, notches, loading mode, alloy composition and mechanical strength. A critical literature review shows contradictory results if a classification by the electrochemical surface state is not applied. Case histories and counter measures illustrate the practical importance of corrosion fatigue in many branches of industry as well as the urgent need for a better knowledge about the mutual influence of the phenomena to get rules by which the engineer can appraise the risk of corrosion fatigue. (orig.)

  4. Silica-based hybrid coatings for corrosion protection of carbon steel. Part I: Effect of pretreatment with phosphoric acid

    OpenAIRE

    Santana, Ianina; Pepe, Andrés; Jiménez Piqué, Emilio; Pellice, Sergio; Ceré, Silvia

    2012-01-01

    This work studies the synthesis and characterization of hybrid organic–inorganic coatings based on silica to improve the corrosion resistance of carbon steel. Hybrid organic–inorganic silica sol–gel coatings were obtained by dipping in an organically modified silica sol synthesized through hydrolysis and condensation of 3-glicidoxipropyl-trimetoxisilano (GPTMS) and tetraethoxysilane (TEOS) in acidic catalysis. The coatings were doped with a cerium salt (Ce(NO3)3·6H2O) and loaded w...

  5. Electrochemical and analytical study of some organic inhibitors used for carbon steel corrosion protection in water cooling systems

    International Nuclear Information System (INIS)

    Water is the main cooling fluid in most industrial applications due to its wide existence in nature and its high specific heat capacity and its thermal conductivity. If pure water was used in cooling systems no problems will occur. However, due to the presence of suspended matter and dissolved solids and gases in water three main problems are encountered in industrial cooling systems; corrosion, scale, and growth of microorganisms which all badly affect the heat transfer efficiency of such system. This study is concerned with utilizing organic inhibitors to control corrosion of mild steel. Three inhibitors were used; 1-hydroxyethylene-1,1- diphosphonic acid (HEDP) as an example of phosphonates, sodium octanoate (C7H15-COONa)as an examples of carboxylates, and 2- phosphono-butane -1,2,4-tricarboxylic acid (PBTC) as an example of a compound having two effective groups: carboxylate and phosphonate (PBTC). City water available at site was used in the present study as a large number of cooling systems utilize water available at site together with mechanical and chemical treatment methods to control corrosion among the two other problems. Two experimental techniques were utilized, potentiodynamic polarization technique and gravimetric technique. The gravimetric technique included a flow loop to simulate the flowing condition of a cooling circuit and a one-day immersion test. Carbon steel specimens, polished to 120 and 600 grit size were used to investigate the effect of surface roughness on the corrosion inhibition efficiency.

  6. Atmospheric corrosion of mild steel

    Directory of Open Access Journals (Sweden)

    Morcillo, M.

    2011-10-01

    Full Text Available The atmospheric corrosion of mild steel is an extensive topic that has been studied by many authors in different regions throughout the world. This compilation paper incorporates relevant publications on the subject, in particular about the nature of atmospheric corrosion products, mechanisms of atmospheric corrosion and kinetics of the atmospheric corrosion process, paying special attention to two matters upon which relatively less information has been published: a the morphology of steel corrosion products and corrosion product layers; and b long-term atmospheric corrosion ( > 10 years.

    La corrosión atmosférica del acero suave es un tema de gran amplitud que ha sido tratado por muchos autores en numerosas regiones del mundo. Este artículo de compilación incorpora publicaciones relevantes sobre esta temática, en particular sobre la naturaleza de los productos de corrosión atmosférica, mecanismos y cinética de los procesos de corrosión atmosférica, prestando una atención especial a dos aspectos sobre los que la información publicada ha sido menos abundante: a morfología de los productos de corrosión del acero y capas de productos de corrosión, y b corrosión atmosférica a larga duración (> 10 años.

  7. Some peculiarities of corrosion of wheel steel

    OpenAIRE

    Alexander SHRAMKO; Alfred KOZLOWSKY; Elena BELAJA; Yuriy PROIDAK; Pinchuk, Sofia; Gubenko, Svetlana

    2009-01-01

    Corrosion mechanism and rate of different chemical composition and structural condition of wheel steel were investigated. It was shown that “white layers”, variation in grain size and banding of wheel steel structure results in corrosion rate. Microstructure of steel from different elements of railway wheels after operation with corrosion was investigated. Wheel steel with addition of vanadium corroded more quickly than steel without vanadium. Non-metallic inclusions are the centre of corrosi...

  8. Corrosion protection of galvanized steel and electroplating steel by decanoic acid in aqueous solution: Electrochemical impedance spectroscopy, XPS and ATR-FTIR

    International Nuclear Information System (INIS)

    The inhibiting action of decanoic acid towards the corrosion behaviour of galvanized steel and electroplating steel in aqueous solution has been studied using electrochemical impedance spectroscopy (EIS) techniques. Data obtained from EIS show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPE) has been used. Results obtained revealed that decanoic acid is an effective inhibitor. The better performance was obtained in the case of electroplating steel. X-ray photoelectron spectroscopy surface analysis shows that, decanoic acid is chemisorbed on surface of galvanized steel and electroplating steel. These studies have shown that the active site for binding the film on metal surface is the anionic carboxylate head. Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy was used to identify the nature of the deposits on the metal surface.

  9. Cathodic protection to control microbiologically influenced corrosion

    International Nuclear Information System (INIS)

    Information about the cathodic protection performance in environments with microbiologically influenced corrosion (MIC) effects is very fragmented and often contradictory. Not enough is known about the microbial effects on cathodic protection effectiveness, criteria, calcareous deposits, corrosion rates and possible hydrogen embrittlement of titanium and some stainless steel condenser tubes. This paper presents a review of cathodic protection systems, describes several examples of cathodic protection in environments with MIC effects and provides preliminary conclusions about cathodic protection design parameters, criteria and effectiveness in MIC environments. 30 refs

  10. Microbial corrosion and cracking in steel. A concept for evaluation of hydrogen-assisted stress corrosion cracking in cathodically protected high-pressure gas transmission pipelines

    DEFF Research Database (Denmark)

    Nielsen, Lars Vendelbo

    An effort has been undertaken in order to develop a concept for evaluation of the risk of hydrogen-assisted cracking in cathodically protected gas transmission pipelines. The effort was divided into the following subtasks: A. Establish a correlation between the fracture mechanical properties of...... high-strength pipeline steel and the concentration of hydrogen present in the steel. B. Determine the degree hydrogen absorption by cathodically protected steel exposed in natural soil sediment, which include activity of sulphate-reducing bacteria (SRB). C. Compare the above points with fracture...

  11. Steel corrosion in radioactive waste storage tanks

    International Nuclear Information System (INIS)

    A collaborative study is being conducted by CNEA and USDOE (Department of Energy of the United States of America) to investigate the effects of tank waste chemistry on radioactive waste storage tank corrosion. Radioactive waste is stored in underground storage tanks that contain a combination of salts, consisting primarily of sodium nitrate, sodium nitrite and sodium hydroxide. The USDOE, Office of River Protection at the Hanford Site, has identified a need to conduct a laboratory study to better understand the effects of radioactive waste chemistry on the corrosion of waste storage tanks at the Hanford Site. The USDOE science need (RL-WT079-S Double-Shell Tanks Corrosion Chemistry) called for a multi year effort to identify waste chemistries and temperatures within the double-shell tank (DST) operating limits for corrosion control and operating temperature range that may not provide the expected corrosion protection and to evaluate future operations for the conditions outside the existing corrosion database. Assessment of corrosion damage using simulated (non-radioactive) waste is being made of the double-shell tank wall carbon steel alloy. Evaluation of the influence of exposure time, and electrolyte composition and/or concentration is being also conducted. (author)

  12. BWR steel containment corrosion

    International Nuclear Information System (INIS)

    The report describes regulatory actions taken after corrosion was discovered in the drywell at the Oyster Creek Plant and in the torus at the Nine Mile Point 1 Plant. The report describes the causes of corrosion, requirements for monitoring corrosion, and measures to mitigate the corrosive environment for the two plants. The report describes the issuances of generic letters and information notices either to collect information to determine whether the problem is generic or to alert the licensees of similar plants about the existence of such a problem. Implementation of measures to enhance the containment performance under severe accident conditions is discussed. A study by Brookhaven National Laboratory (BNL) of the performance of a degraded containment under severe accident conditions is summarized. The details of the BNL study are in the appendix to the report

  13. Development of low-temperature galvanizing and its application for corrosion protection of high-strength steels; Entwicklung einer niedrigschmelzenden Legierung und deren Applikation zum Korrosionsschutz hochfester Staehle

    Energy Technology Data Exchange (ETDEWEB)

    Wielage, B.; Lampke, T.; Steinhaeuser, S. [Technische Universitaet Chemnitz (Germany). Institut fuer Werkstoffwissenschaft und Werkstofftechnik; Strobel, C. [Fachhochschule Ingolstadt (Germany); Merklinger, V.

    2008-12-15

    Apart from reliability and quality, vehicle safety and cost efficiency are the decisive criteria for automobile manufacturers. Corrosion protection plays a decisive role because it increases the service life. The ultra-high-strength steels are materials which exhibit high lightweight potential as well as a very good energy absorption capacity because of their mechanical properties. In connection with the possibility of hot forming, they are predestined for the fabrication of complicated, load-compatible shapes in the crash-relevant frame and body construction. The application of these steel qualities has been carried out in structural parts which are protected from corrosion by a hot-dip coat of FeAl7 - the so-called Usibor. However, at the moment there is no ready-for-production solution for later corrosion protection of already hot-formed parts. Therefore, a corrosion protection system on the basis of conventional low-temperature galvanizing processes has been developed and utilized. First, the softening behavior of the highly-resistant 22MnB5 substrate was analyzed. Afterwards, a galvanizing system was developed and applied. The corrosion protection coatings were characterized with regard to their structure and corrosion protection potential. As a result, a significant improvement of the corrosion behaviour has occurred. (Abstract Copyright [2008], Wiley Periodicals, Inc.) [German] Neben Zuverlaessigkeit und Qualitaet sind vor allem Fahrzeugsicherheit und Wirtschaftlichkeit entscheidende Kriterien fuer den Automobilhersteller. Der Korrosionsschutz spielt dabei eine herausragende Rolle, da hierdurch die Lebens- und Gebrauchsdauer erhoeht wird. Mit der Bereitstellung hoechstfester Stahlqualitaeten stehen Werkstoffe zur Verfuegung, die auf Grund ihrer mechanischen Eigenschaften ein hohes Leichtbaupotenzial sowie ein sehr gutes Energieabsorptionsvermoegen aufweisen. In Verbindung mit der Moeglichkeit der Warmformgebung sind sie damit praedestiniert fuer die Herstellung komplizierter, beanspruchungsgerechter Formen im crashrelevanten Karosseriebereich. Der Einsatz dieser Stahlqualitaeten erfolgt bislang in Strukturbauteilen, die mit einem Schmelztauchueberzug aus FeAl7, sog. Usibor, vor Korrosion geschuetzt sind. Jedoch besteht zurzeit keine serienreife Loesung fuer den nachtraeglichen Korrosionsschutz von bereits warmumgeformten Bauteilen. Deshalb wurde ein Korrosionsschutzsystem auf Basis des herkoemmlichen Schmelztauchverzinkungsprozesses entwickelt und appliziert. Zunaechst wurde das Entfestigungsverhalten des hoechstfesten Substrats 22MnB5 analysiert. Anschliessend wurde ein Legierungssystem entwickelt und appliziert. Die so entstandenen Korrosionsschutzschichten wurden hinsichtlich ihrer Struktur und des Korrosionsschutzpotenzials charakterisiert. Im Ergebnis tritt eine deutliche Verbesserung des Korrosionsverhaltens ein. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  14. Volatile corrosion inhibitor film formation on carbon steel surface and its inhibition effect on the atmospheric corrosion of carbon steel

    Science.gov (United States)

    Zhang, Da-quan; An, Zhong-xun; Pan, Qing-yi; Gao, Li-xin; Zhou, Guo-ding

    2006-11-01

    A novel volatile corrosion inhibitor (VCI), bis-piperidiniummethyl-urea (BPMU), was developed for temporary protection of carbon steel. Its vapor corrosion inhibition property was evaluated under simulated operational conditions. Electrochemical impedance spectroscopy was applied to study the inhibition effect of BPMU on the corrosion of carbon steel with a thin stimulated atmospheric corrosion water layers. Adsorption of BPMU on carbon steel surfaces was investigated by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The results indicate that BPMU can form a protective film on the metal surface, which protects the metal against further corrosion. The structure of the protective film was suggested as one BPMU molecule chelated with one Fe atom to form a complex with two hexa-rings.

  15. Volatile corrosion inhibitor film formation on carbon steel surface and its inhibition effect on the atmospheric corrosion of carbon steel

    International Nuclear Information System (INIS)

    A novel volatile corrosion inhibitor (VCI), bis-piperidiniummethyl-urea (BPMU), was developed for temporary protection of carbon steel. Its vapor corrosion inhibition property was evaluated under simulated operational conditions. Electrochemical impedance spectroscopy was applied to study the inhibition effect of BPMU on the corrosion of carbon steel with a thin stimulated atmospheric corrosion water layers. Adsorption of BPMU on carbon steel surfaces was investigated by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The results indicate that BPMU can form a protective film on the metal surface, which protects the metal against further corrosion. The structure of the protective film was suggested as one BPMU molecule chelated with one Fe atom to form a complex with two hexa-rings

  16. Corrosion inhibition performance of 2-mercaptobenzimidazole and 2-mercaptobenzoxazole compounds for protection of mild steel in hydrochloric acid solution

    Energy Technology Data Exchange (ETDEWEB)

    Mahdavian, M., E-mail: mahdavian@aut.ac.i [Department of Surface Coatings and Corrosion, Institute for Color Science and Technology, P.O. Box 16765-654, Tehran (Iran, Islamic Republic of); Ashhari, S. [Department of Surface Coatings and Corrosion, Institute for Color Science and Technology, P.O. Box 16765-654, Tehran (Iran, Islamic Republic of)

    2010-02-01

    The effect of some mercapto functional azole compounds on the corrosion of mild steel in 1 M hydrochloric acid solution was studied by polarization and electrochemical impedance spectroscopy (EIS). Polarization studies showed depression of cathodic and anodic polarization curves in the presence of mercapto functional azole compounds, indicating mixed type corrosion inhibition of the compounds. Double layer capacitance and charge transfer resistance values were derived from EIS results. Changes in impedance parameters are indicative of adsorption of these compounds on the metal surface. Surface analysis SEM/EDX showing presence of sulfur on the surface confirmed the adsorption of the azole compounds on the mild steel surface as showed by electrochemical methods. Both compounds contain a pyridine-like nitrogen atom and a sulfur atom in their molecular structure, while they differ in only one heteroatom: oxygen in the oxazole ring and pyrrole-like nitrogen in the imidazole ring. The results of the electrochemical techniques revealed that changing the pyrrole like nitrogen atom to oxygen atom in the azole ring results in a decrease of corrosion inhibition performance in hydrochloric acid solution, which could be related to more negative charge on pyrrole-like nitrogen atom in comparison to oxygen atom as depicted by quantum chemical calculations.

  17. Corrosion inhibition performance of 2-mercaptobenzimidazole and 2-mercaptobenzoxazole compounds for protection of mild steel in hydrochloric acid solution

    International Nuclear Information System (INIS)

    The effect of some mercapto functional azole compounds on the corrosion of mild steel in 1 M hydrochloric acid solution was studied by polarization and electrochemical impedance spectroscopy (EIS). Polarization studies showed depression of cathodic and anodic polarization curves in the presence of mercapto functional azole compounds, indicating mixed type corrosion inhibition of the compounds. Double layer capacitance and charge transfer resistance values were derived from EIS results. Changes in impedance parameters are indicative of adsorption of these compounds on the metal surface. Surface analysis SEM/EDX showing presence of sulfur on the surface confirmed the adsorption of the azole compounds on the mild steel surface as showed by electrochemical methods. Both compounds contain a pyridine-like nitrogen atom and a sulfur atom in their molecular structure, while they differ in only one heteroatom: oxygen in the oxazole ring and pyrrole-like nitrogen in the imidazole ring. The results of the electrochemical techniques revealed that changing the pyrrole like nitrogen atom to oxygen atom in the azole ring results in a decrease of corrosion inhibition performance in hydrochloric acid solution, which could be related to more negative charge on pyrrole-like nitrogen atom in comparison to oxygen atom as depicted by quantum chemical calculations.

  18. Sol-gel deposition of ZrO2 films in air and in oxygen-free atmospheres for chemical protection of 304 stainless steel : a comparative corrosion study

    OpenAIRE

    Aegerter, Michel A.; P. De Lima-Neto; Perdomo, L. F.; Avaca, Luis A.

    1999-01-01

    ZrO2 coatings for corrosion protection were deposited on 304 stainless steel by sol-gel method using zirconium propoxide as precursor and densified in air and in oxygen-free (argon or nitrogen) atmospheres. XRD and IR data of the films were practically independent of the atmosphere used in the densification step showing that the ceramic oxide is properly formed from the precursor. The corrosion behavior of the stainless steel substrate was studied by potentiodynamic polarization curves in the...

  19. Inhibition of the Corrosion of Mild Steel in Acid Media by Naturally Occurring Acacia Senegal

    OpenAIRE

    Urvija Garg; R. K. Tak

    2010-01-01

    The inhibition of corrosion of mild steel in HCl solution by naturally occurring Acacia Senegal has been studied in relation to the concentration of inhibitor and concentration of corrosive medium. It has been observed that the Acacia Senegal alcoholic extract acts as a good corrosion inhibitor in hydrochloric acid solution and the adsorption of the extract provides a good protection against mild steel corrosion.

  20. MECHANICAL PROPERTIES AND CORROSION PROTECTION OF CARBON STEEL COATED WITH AN EPOXY BASED POWDER COATING CONTAINING MONTMORILONITE FUNCTIONALIZED WITH SILANE

    Directory of Open Access Journals (Sweden)

    Paula Tibola Bertuoli

    2014-06-01

    Full Text Available In the present work the MMT-Na+ clay was functionalized with 3-aminopropyltriethoxysilane (?-APS and incorporated in a commercial formulation epoxy-based powder coating in a proportion of 8 wt% and applied on 1008 carbon steel panels by electrostatic spray. Adhesion, flexibility, impact and corrosion performance in salt spray chamber tests were performed to evaluate the coatings. The presence of clay did not affect the mechanical properties of the film, however greater subcutaneous migration was assessed after the completion of salt spray testing, which can compromise the use of paints obtained as primers.

  1. The Corrosion Protection of Metals by Ion Vapor Deposited Aluminum

    Science.gov (United States)

    Danford, M. D.

    1993-01-01

    A study of the corrosion protection of substrate metals by ion vapor deposited aluminum (IVD Al) coats has been carried out. Corrosion protection by both anodized and unanodized IVD Al coats has been investigated. Base metals included in the study were 2219-T87 Al, 7075-T6 Al, Titanium-6 Al-4 Vanadium (Ti-6Al-4V), 4130 steel, D6AC steel, and 4340 steel. Results reveal that the anodized IVD Al coats provide excellent corrosion protection, but good protection is also achieved by IVD Al coats that have not been anodized.

  2. Corrosion behavior of 2205 duplex stainless steel.

    Science.gov (United States)

    Platt, J A; Guzman, A; Zuccari, A; Thornburg, D W; Rhodes, B F; Oshida, Y; Moore, B K

    1997-07-01

    The corrosion of 2205 duplex stainless steel was compared with that of AISI type 316L stainless steel. The 2205 stainless steel is a potential orthodontic bracket material with low nickel content (4 to 6 wt%), whereas the 316L stainless steel (nickel content: 10 to 14 wt%) is a currently used bracket material. Both stainless steels were subjected to electrochemical and immersion (crevice) corrosion tests in 37 degrees C, 0.9 wt% sodium chloride solution. Electrochemical testing indicates that 2205 has a longer passivation range than 316L. The corrosion rate of 2205 was 0.416 MPY (milli-inch per year), whereas 316L exhibited 0.647 MPY. When 2205 was coupled to 316L with equal surface area ratio, the corrosion rate of 2205 reduced to 0.260 MPY, indicating that 316L stainless steel behaved like a sacrificial anode. When 316L is coupled with NiTi, TMA, or stainless steel arch wire and was subjected to the immersion corrosion test, it was found that 316L suffered from crevice corrosion. On the other hand, 2205 stainless steel did not show any localized crevice corrosion, although the surface of 2205 was covered with corrosion products, formed when coupled to NiTi and stainless steel wires. This study indicates that considering corrosion resistance, 2205 duplex stainless steel is an improved alternative to 316L for orthodontic bracket fabrication when used in conjunction with titanium, its alloys, or stainless steel arch wires. PMID:9228844

  3. Synthesis and application of hybrid polymer composites based on silver nanoparticles as corrosion protection for line pipe steel.

    Science.gov (United States)

    Atta, Ayman M; El-Mahdy, Gamal A; Al-Lohedan, Hamad A; Ezzat, Abdurrahman O

    2014-01-01

    A facile method was developed to synthesize in high yield dispersed silver nanoparticles (AgNPs) with small particle sizes of less than 10 nm. Silver nitrate was reduced to silver nanoparticles by p-chloroaniline in the presence of polyoxyethylene maleate 4-nonyl-2-propylene-phenol (NMA) as a stabilizer. The produced AgNPs were used to prepare hybrid polymer based on N-isopropylacrylamide (NIPAm), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), N,N-methylenebisacrylamide (MBA) and potassium persulfate (KPS) using a semi-batch solution polymerization method. The prepared AgNPs and hybrid polymer were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) patterns and transmission electron microscopy (TEM). The corrosion inhibition activity of the AgNPs and hybrid polymer towards steel corrosion in the presence of hydrochloric acid has been investigated by polarization and electrochemical impedance spectroscopy (EIS) methods. Polarization measurements indicate that the AgNPs and hybrid polymer acts as a mixed type-inhibitor and the inhibition efficiency increases with inhibitor concentration. The results of potentiodynamic polarization and EIS measurements clearly showed that the inhibition mechanism involves blocking of the steel surface by inhibitor molecules via adsorption. PMID:24840897

  4. Next generation corrosion protection for the automotive industry

    OpenAIRE

    Hosking, Niamh C.

    2008-01-01

    Vehicle bodies are generally constructed from galvanized steel, which, together with phosphate and e-coat paint treatments, ensures corrosion resistance. The use of these materials alone cannot provide adequate corrosion protection to certain features that are inherent to vehicle body construction but are also vulnerable to corrosion, such as cut edges of panels and creviced joints. The use of further corrosion protection measures, (e.g. sealers, lacquers and waxes), is undesirable because th...

  5. Pitting corrosion protection of low nickel stainless steel by electropolymerized conducting polymer coating in 0.5 M NaCl solution

    Indian Academy of Sciences (India)

    T Dhanabal; G Amirthaganesan; J Ravichandran

    2011-06-01

    Conducting polymers of polyaniline (PANi) and poly(o-phenylenediamine) (PoPD) were electropolymerized by cyclic voltammetric technique on low nickel stainless steel (LN SS) in H2SO4 solution containing aniline and -phenylenediamine monomers. The coatings were characterized by Fourier transform infrared spectroscopy, UV-visible and scanning electron microscopic techniques and the results are discussed. The corrosion protective properties of PANi and PoPD coatings on LN SS in 0.5 M NaCl were evaluated using potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) techniques. The potentiodynamic polarization and electrochemical impedance spectroscopic results indicate that the PoPD coating inhibits the corrosion of LN SS in 0.5 M NaCl solution more effectively than PANi.

  6. Electrodeposition of polyaniline–carbon nanotubes composite films and investigation on their role in corrosion protection of austenitic stainless steel by SNIFTIR analysis

    International Nuclear Information System (INIS)

    Composite films of polyaniline (PANI) and carbon nanotubes (CNTs) were prepared by electrochemical co-deposition from solutions of the corresponding monomer containing two different kinds of CNTs. The first type was commercial (diameter = 110–170 nm, length = 5–9 ?m) and the second one was home-made (diameter = 30 nm, length = 5–20 ?m). The electrochemical behaviour of PANI–CNTs composite films was investigated with Cyclic Voltammetry and the surface morphology was analysed by Scanning Electron Microscopy (SEM). Subtractively Normalised Interfacial FT-IR procedure was used to investigate the presence of corrosion products when the films were deposited on stainless steel substrates and exposed to acid environment. The spectral investigations were utilised to understand the role of composite films in the corrosion protection and to discriminate the best performance CNTs.

  7. Complex Protection of Vertical Stainless Steel Tanks

    Directory of Open Access Journals (Sweden)

    Fakhrislamov Radik Zakievich

    2014-03-01

    Full Text Available The authors consider the problem of fail-safe oil and oil products storage in stainless steel tanks and present the patented tank inner side protection technology. The latter provides process, ecological and fire safety and reducing soil evaporation of oil products, which is a specific problem. The above-mentioned technology includes corrosion protection and heat insulation protection providing increase of cover durability and RVS service life in general. The offered technological protection scheme is a collaboration of the author, Steel Paint GmbH firm and JSC “Koksokhimmontazhproyekt”. PU foam unicomponent materials of Steel Paint GmbH firm provide the protection of tank inner side and cover.

  8. Assessing resistance of stabilized corrosion resistant steels to intergranular corrosion

    International Nuclear Information System (INIS)

    Resistance to intergranular corrosion was determined for four types of titanium-stabilized steels from the coefficients of stabilization efficiency according to the degree the chemical composition was known. The ATA SUPER steel showed the highest resistance parameter value. The resistance of this type of steel of a specific composition, showing a relatively low value of mean nitrogen content was compared with steel of an optimized chemical composition and with low-carbon niobium stabilized, molybdenum modified steels. The comparison showed guarantees of a sufficient resistance of the steel to intergranular corrosion. The method of assessing the resistance to intergranular corrosion using the calculation of the minimum content of Cr', i.e., the effective chromium content, and the maximum effective carbon content C' giving the resistance parameter k seems to be prospective for practical use in the production of corrosion resistant steels. (author). 1 tab., 5 figs., 15 refs

  9. Thermally Sprayed Aluminum (TSA) with Cathodic Protection as Corrosion Protection for Steel in Natural Seawater : Characterization of Properties on TSA and Calcareous Deposit

    OpenAIRE

    Egtvedt, Solveig

    2011-01-01

    Cathodic protection is an effective corrosion protection for structures submerged in seawater. In addition to applying the current need to lower the metal below the protection potential, a resulting increase in interfacial pH leads to precipitation of calcareous deposit. This deposited layer act as a barrier against oxygen diffusion on the surface, hence lowering the current demand of the structure. However, this layer will also hinder the thermal conductivity, and is therefore unwanted at th...

  10. AC-Induced Corrosion of Underground Steel Pipelines. Faradaic Rectification under Cathodic Protection: I. Theoretical Approach with Negligible Electrolyte Resistance

    Scientific Electronic Library Online (English)

    Ibrahim, Ibrahim; Bernard, Tribollet; Hisasi, Takenouti; Michel, Meyer.

    2015-01-01

    Full Text Available Tubulações subterrâneas protegidos por um revestimento grosso e por polarização catódica podem sofrer danos externos sérios por corrosão na presença de tensão de corrente alternada (AC) dispersa induzida por sistemas industriais de transporte elétrico de [...] alta tensão, como linhas de tensão ou ferrovias eletrizadas. A origem do aumento da corrosão vem da não-linearidade das características corrente-potencial da interface metal-solo. Neste trabalho, avaliaremos teoricamente o aumento da densidade de corrente de corrosão e o deslocamento de potencial induzido por um sinal AC de alta amplitude a modelos de sistemas sofrendo corrosão: curvas de polarização anódicas obedecendo uma lei exponencial em relação ao potencial, e processo catódico sob a cinética de ativação-difusão mista. A originalidade do presente trabalho se encontra no uso de um número relativamente pequeno de variáveis sem dimensão para descrever a retificação faradaica no deslocamento do potencial e no aumento da corrente de corrosão. Neste artigo, o efeito da resistência do eletrólito foi negligenciado. Abstract in english Underground pipelines protected with a thick coating and by cathodic polarisation may suffer a serious external corrosion damage in the presence of stray alternating current (AC) voltage induced by high voltage industrial electric transport system, such a [...] s power lines or electrified railroads. The origin of the corrosion enhancement comes from the nonlinearity of the currentpotential characteristics of the metal-soil interface. In this paper, we will theoretically evaluate the increase of the corrosion current density and the potential shift induced by a high amplitude AC signal to models of corroding systems: anodic polarisation curves obeying an exponential law with respect to the potential, and cathodic process under the mixed activation-diffusion kinetics. The originality of the present work lies in the use of a relatively small number of dimensionless variables to describe the faradaic rectification for the corrosion potential shift and the corrosion current enhancement. In this article, the effect of the electrolyte resistance was neglected.

  11. Effect of cathodic protection on the state of steel reinforcement

    International Nuclear Information System (INIS)

    Damage of reinforced concrete structures is mainly caused by chloride or carbonation induced corrosion of steel. Cathodic protection is a very effective measure for corrosion control of steel in concrete, especially in chloride contaminated concrete. In this paper, effect of cathodic protection on the state of steel reinforcement is presented. Cathodic polarization of reinforcements in concrete was done under different submerged conditions. Cyclic potentiodynamic tests were used to determine the effect of cathodic protection on the behavior of the steel. Pitting appeared on the non-protected steel, but was not observed on the cathodically protected steel. microscopic photographs show that a close film exists on the protected steel, while the non-protected steel's film is loose. Investigated results have proved the effect of cathodic protection in restoring or strengthening passive film on the steel reinforcement

  12. Natural Corrosion Inhibitors for Steel Reinforcement in Concrete — a Review

    Science.gov (United States)

    Raja, Pandian Bothi; Ghoreishiamiri, Seyedmojtaba; Ismail, Mohammad

    2015-04-01

    Reinforced concrete is one of the widely used construction materials for bridges, buildings, platforms and tunnels. Though reinforced concrete is capable of withstanding a large range of severe environments including marine, industrial and alpine conditions, there are still a large number of failures in concrete structures for many reasons. Either carbonation or chloride attack is the main culprit which is due to depassivation of reinforced steel and subsequently leads to rapid steel corrosion. Among many corrosion prevention measures, application of corrosion inhibitors play a vital role in metal protection. Numerous range of corrosion inhibitors were reported for concrete protection that were also used commercially in industries. This review summarizes the application of natural products as corrosion inhibitors for concrete protection and also scrutinizes various factors influencing its applicability.

  13. A STUDY OF CORROSION AND STRESS CORROSION CRACKING OF CARBON STEEL NUCLEAR WASTE STORAGE TANKS

    International Nuclear Information System (INIS)

    The Hanford reservation Tank Farms in Washington State has 177 underground storage tanks that contain approximately 50 million gallons of liquid legacy radioactive waste from cold war plutonium production. These tanks will continue to store waste until it is treated and disposed. These nuclear wastes were converted to highly alkaline pH wastes to protect the carbon steel storage tanks from corrosion. However, the carbon steel is still susceptible to localized corrosion and stress corrosion cracking. The waste chemistry varies from tank to tank, and contains various combinations of hydroxide, nitrate, nitrite, chloride, carbonate, aluminate and other species. The effect of each of these species and any synergistic effects on localized corrosion and stress corrosion cracking of carbon steel have been investigated with electrochemical polarization, slow strain rate, and crack growth rate testing. The effect of solution chemistry, pH, temperature and applied potential are all considered and their role in the corrosion behavior will be discussed

  14. Cathode protection for underground steel tanks

    International Nuclear Information System (INIS)

    Cathodic protection of underground petroleum storage tanks and piping systems is acceptable for both economic and ecological reasons. With out the cathodic protection of underground steel reservoirs, short time after the exploitation, there was a bore as a result of underground corrosion. The bore causes ecological consequences and at the same time its repair needs big investments. Furthermore, there are great number of tanks placed near cities, so in the future this problem needs a special attention in order to preserve ecological surrounding. The topic of this paper is underground corrosion as well as cathodic protection of steel tanks for oil derivatives storage. (author)

  15. PROTECCIÓN CONTRA LA CORROSIÓN POR SALES FUNDIDAS DE UN ACERO AL CARBONO POR ROCIADO TERMICO / (PROTECTION AGAINST THE HOT CORROSION OF CARBON STEEL BY THERMAL SPRAYING)

    Scientific Electronic Library Online (English)

    JOSE, MARULANDA; ANDRÉS, GARCÍA; JOSE, VITOLA.

    2009-06-01

    Full Text Available Se evaluó la corrosión por sales fundidas mediante la técnica gravimétrica en un acero de bajo carbono rociado térmicamente con una aleación de acero inoxidable, en una mezcla de sal con 20% Na2SO4 - 80% V2O5, entre 700ºC - 850ºC. Los resultados de las pruebas gravimétricas mostraron una deficiente [...] protección de la capa rociada térmicamente y se presentó alta degradación en el recubrimiento protector, debido a que las temperaturas de exposición fueron mayores que las temperaturas de fusión de las sales. Se concluyó que la velocidad de corrosión aumenta con la temperatura y disminuye con el tiempo de exposición. Abstract in english The hot corrosion was evaluated by gravimetric techniques in a low carbon steel protected by thermal spraying with a stainless alloy, in a mixture of salt 20% Na2SO4 - 80% V2O5, between 700ºC - 850ºC.. The gravimetric tests showed a weak protection of the layer thermal spraying. The test results sho [...] wed a weak protection of the layer thermally sprayed and presented high degradation in the protective coatings because the exposure temperatures were higher than merging temperatures of the salts. It was concluded that the rate of corrosion increases with temperature and decreases with time of exposure.

  16. Characteristics of Corrosion Product Layer Formed on Weathering Steel Exposed to the Tropical Climate of Vietnam

    OpenAIRE

    Le Thi Hong Lien; Hoang Lam Hong

    2013-01-01

    The weathering steel (Corten B) was exposed to out-door atmosphere of Hanoi (urban site) and Donghoi (marine site). The results showed the protective ability of corrosion product layer formed on weathering steel in the initial stage. The SEM-EDX analysis detected the presence of chromium and copper in the inner layers of corrosion product formed on weathering steel. These elements improved corrosion resistance of corrosion product layers. In addition, the dense ?-FeOOH phase were appeared ea...

  17. Corrosion of Steel in Concrete, Part I – Mechanisms

    DEFF Research Database (Denmark)

    Küter, André; MØller, Per

    2006-01-01

    Throughout the world reinforced concrete is the most widely used construction material for buildings and civil engineering structures. Most reinforced concrete structures have performed satisfactory over many decades, but there still is an unacceptable large number of structures that deteriorate prematurely. Reinforcement corrosion is identified to be the foremost cause of deterioration. Steel in concrete is normally protected by a passive layer due the high alkalinity of the concrete pore solution; corrosion is initiated by neutralization through atmospheric carbon dioxide and by ingress of depassivation ions, especially chloride ions. The background and consequences of deterioration of reinforced concrete structures caused by steel corrosion are summarized. Selected corrosion mechanisms postulated in the literature are briefly discussed and related to observations. The key factors controlling initiation and propagation of corrosion of steel in concrete are outlined.

  18. Corrosion pitting of stainless steels

    International Nuclear Information System (INIS)

    The work presented elucidates the problem of distinguishing between anodic and cathodic sites of pitting corrosion in standard stainless steels 304 and 316. In the present work pitting has been formed by the immersion of samples in magnesium chloride solution (MgCl2) for a given time and this was confirmed by Scanning Auger Microscope (SAM) study. These results show the presence of the elements at the pits and surrounding pits. The following conclusion was obtained from the result: the resistivity of the passive film in MgCl2 solution increases with increasing amount of chromium content in the film. (author)

  19. Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    2000-01-01

    control the corrosion. A number of monitoring techniques is industrially used today, and the applicability and reliability of these for monitoring MIC is evaluated. Coupons and ER are recommended as necessary basic techniques even though localised corrosion rate cannot be measured. FSM measures general...... might be used for detection of MIC. EN is a suitable technique to characterise the type of corrosion attack, but is unsuitable for corrosion rate estimation. The concentric electrodes galvanic probe arrangement initiates localised corrosion on the anode and seems applicable to evaluate the risk of MIC......Microbially influenced corrosion (MIC) of carbon steel may occur in media with microbiological activity of especially sulphate-reducing bacteria, e.g. on pipelines buried in soil and on marine structures. MIC of carbon steel must be monitored on-line in order to provide an efficient protection and...

  20. Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    2000-01-01

    Microbially influenced corrosion (MIC) of carbon steel may occur in media with microbiological activity of especially sulphate-reducing bacteria, e.g. on pipelines buried in soil and on marine structures. MIC of carbon steel must be monitored on-line in order to provide an efficient protection and control the corrosion. A number of monitoring techniques is industrially used today, and the applicability and reliability of these for monitoring MIC is evaluated. Coupons and ER are recommended as necessary basic techniques even though localised corrosion rate cannot be measured. FSM measures general corrosion and detects localised corrosion, but the sensitivity is not high enough for monitoring initiation of pitting and small attacks. Electrochemical techniques as LPR and EIS give distorted data and unreliable corrosion rates, when biofilm and corrosion products cover the steel surface. However, EIS might be used for detection of MIC. EN is a suitable technique to characterise the type of corrosion attack, but is unsuitable for corrosion rate estimation. The concentric electrodes galvanic probe arrangement initiates localised corrosion on the anode and seems applicable to evaluate the risk of MIC. Hydrogen permeation measurements are very useful to monitor hydrogen induced cracking accelerated by MIC.

  1. Corrosion protection with eco-friendly inhibitors

    Science.gov (United States)

    Shahid, Muhammad

    2011-12-01

    Corrosion occurs as a result of the interaction of a metal with its environment. The extent of corrosion depends on the type of metal, the existing conditions in the environment and the type of aggressive ions present in the medium. For example, CO3-2 and NO-3 produce an insoluble deposit on the surface of iron, resulting in the isolation of metal and consequent decrease of corrosion. On the other hand, halide ions are adsorbed selectively on the metal surface and prevent formation of the oxide phase on the metal surface, resulting in continuous corrosion. Iron, aluminum and their alloys are widely used, both domestically and industrially. Linear alkylbenzene and linear alkylbenzene sulfonate are commonly used as detergents. They have also been found together in waste water. It is claimed that these chemicals act as inhibitors for stainless steel and aluminum. Release of toxic gases as a result of corrosion in pipelines may lead in certain cases to air pollution and possible health hazards. Therefore, there are two ways to look at the relationship between corrosion and pollution: (i) corrosion of metals and alloys due to environmental pollution and (ii) environmental pollution as a result of corrosion protection. This paper encompasses the two scenarios and possible remedies for various cases, using 'green' inhibitors obtained either from plant extracts or from pharmaceutical compounds. In the present study, the effect of piperacillin sodium as a corrosion inhibitor for mild steel was investigated using a weight-loss method as well as a three-electrode dc electrochemical technique. It was found that the corrosion rate decreased as the concentration of the inhibitor increased up to 9×10-4?M 93% efficiency was exhibited at this concentration.

  2. Corrosion protection with eco-friendly inhibitors

    International Nuclear Information System (INIS)

    Corrosion occurs as a result of the interaction of a metal with its environment. The extent of corrosion depends on the type of metal, the existing conditions in the environment and the type of aggressive ions present in the medium. For example, CO3−2 and NO−3 produce an insoluble deposit on the surface of iron, resulting in the isolation of metal and consequent decrease of corrosion. On the other hand, halide ions are adsorbed selectively on the metal surface and prevent formation of the oxide phase on the metal surface, resulting in continuous corrosion. Iron, aluminum and their alloys are widely used, both domestically and industrially. Linear alkylbenzene and linear alkylbenzene sulfonate are commonly used as detergents. They have also been found together in waste water. It is claimed that these chemicals act as inhibitors for stainless steel and aluminum. Release of toxic gases as a result of corrosion in pipelines may lead in certain cases to air pollution and possible health hazards. Therefore, there are two ways to look at the relationship between corrosion and pollution: (i) corrosion of metals and alloys due to environmental pollution and (ii) environmental pollution as a result of corrosion protection. This paper encompasses the two scenarios and possible remedies for various cases, using 'green' inhibitors obtained either from plant extracts or from pharmaceutical compounds. In the present study, the effect of piperacillin sodium as a corrosion inhibitor for mild steel was investigated using a weight-loss method as well as a three-electrode dc electrochemical technique. It was found that the corrosion rate decreased as the concentration of the inhibitor increased up to 9×10−4 M; 93% efficiency was exhibited at this concentration. (review)

  3. Galvanic Corrosion of a Carbon Steel-Stainless Steel Couple in Sulfide Solutions

    Science.gov (United States)

    Dong, C. F.; Xiao, K.; Li, X. G.; Cheng, Y. F.

    2011-12-01

    The galvanic corrosion behavior of carbon steel-stainless steel couples with various cathode/anode area ratios was investigated in S 2--containing solutions, which were in equilibrium with air, by electrochemical measurements, immersion test, and surface characterization. It is found that the galvanic corrosion effect on carbon steel anode increases with the cathode/anode area ratios, and decreases with the increasing concentration of S2- in the solution. A layer of sulfide film is formed on carbon steel surface, which protects it from corrosion. When the cathode/anode area ratio is 1:1, the potentiodynamic polarization curve measurement and the weight-loss determination give the identical measurement of the galvanic corrosion effect. With the increase of the cathode/anode area ratio, the electrochemical method may not be accurate to determine the galvanic effect. The anodic dissolution current density of carbon steel cannot be approximated simply with the galvanic current density.

  4. METHOD FOR ARRANGEMENT OF HIGH-STRENGTH CORROSION-RESISTANT FOR EFFICIENT PROTECTION OF STEEL PIPELINES OPERATED IN THE EXTREME NORTH

    Directory of Open Access Journals (Sweden)

    I. S. Surovtsev

    2011-11-01

    Full Text Available Problem statement. At present, the problem of main pipeline protection from corrosion is extremelyimportant. Principal gas-transport routes have the biggest length in the North areas whereclimatic and geotechnical conditions are adverse. Scientists of Voronezh State University of Architectureand Civil Engineering have developed new material, rubber concrete. This material isbased on liquid oligodienes and has unique set of operational characteristics. The material can beefficiently used as insulation material for metal pipe in the conditions of the Extreme North.Results. The method for arrangement of protective coating of metal pipe is developed on the basisof rubber concrete. The method is patented. Laboratory device which allows one to perform structuresformation of rubber mastic on the surface of metal pipe is constructed. Physicomechanicalproperties of rubber concrete as insulation material for steel pipes are determined.Conclusions. The results of experiments allow us to draw a conclusion on the expediency of the useof rubber concrete as a protection coating material for steel pipes operated in the Extreme North.

  5. Influence of corrosion on the light steel gauge framing

    Directory of Open Access Journals (Sweden)

    Maria Vladimirovna Ananina

    2014-07-01

    Full Text Available Construction technology based on the light steel gauge construction is a frame technology, allowing erecting houses in a short time. The essence of this technology is using panels of light steel galvanized perforated and non-perforated profile, which form the metal frame of the building. There are many characteristics of LSGF that have been explored for nowadays. One of the main such characteristics is corrosion resistance. Corrosion protection of light steel structures are extremely important. For the construction of steel structures, electrochemical corrosion has the main importance. Electrochemical corrosion processes take place in aqueous solutions. When the metal surface in contact with the electrolyte solution there is an interaction of the metal with charged particles of solution and the transition metal ions into the solution. It is known that stress corrosion cracking occurs under the action of tensile stresses, which cause dilation of cracks. Compressive stresses counteract cracking, causing the closure of cracks. Growth of carbon content in steel leads to growth of its resistance to stress corrosion including in environments of nitrides and hydroxides. Reducing the grain size of steel increases its resistance to cracking, which is associated with the increase of cracking of path and strength increase. In a high risk of corrosion, it is better to use solid, closed sections than lattice. Greater consumption of steel will pay off as a result of increasing physical strength of the structure. Currently, the most common method of corrosion protection is the application of coatings in a layer of paint. They concede superiority in terms of stability, plated and metal coatings, but more are available.

  6. Microbial corrosion inhibition of mild steel in salty water environment

    International Nuclear Information System (INIS)

    The use of antimicrobial corrosion inhibitor is increasingly being curtailed by recent corrosion restrictions. This paper represents the results of the study of new biocide, antimicrobial corrosion inhibitor named 8-hydroxy-N'-(2-(quinolin-8-yloxy)acetyl)quinoline-5-sulfonohydrazide (HQS) was used to inhibit corrosion causing sulphate reducing bacteria (SRB). The effects of the inhibitor on mild steel dissolution in salty water environment were studied through weight loss measurements, electrochemical and microorganism tests. The results obtained from this study show that, the new inhibitor can decrease corrosion and microbial growth under the conditions tested. The mass loss for the protected mild steel coupons shows lower corrosion rate compared to the unprotected once. Cyclic polarization test reveals that, the biocide minimizes the pitting area (hysteresis). The nature of protective film formed on mild steel was studied by scanning electron microscopy (SEM). SEM images revealed that, the corrosion inhibition by the HQS on the mild steel surface significantly improved in the presence of biocide

  7. Low-temperature atomic layer deposition of Al2O3 thin coatings for corrosion protection of steel: Surface and electrochemical analysis

    International Nuclear Information System (INIS)

    Highlights: ? 10-100 nm Alumina coatings grown by ALD at 160 oC for protection of steel. ? Al2O3 stoichiometry of the coating and trace contamination by growth precursors. ? Iron oxide and siloxane presence at the buried coating/steel interface. ? Exponential decay of coating porosity over four orders of magnitude with thickness increase. ? Coating thickness increase required to seal the defective first deposited 10 nm. - Abstract: ToF-SIMS, XPS, voltammetry and EIS investigation of the anti-corrosion properties of thin (10, 50 and 100 nm) alumina coatings grown by atomic layer deposition at 160 oC on steel is reported. Surface analysis shows a thickness-independent Al2O3 stoichiometry of the coating and trace contamination by the growth precursors. The buried coating/alloy interface has iron oxide formed in ambient air and/or resulting from the growth of spurious traces in the initial stages of deposition. Electrochemical analysis yields an exponential decay of the coating porosity over four orders of magnitude with increasing thickness, achieved by sealing of the more defective first deposited 10 nm.

  8. Low-temperature atomic layer deposition of Al{sub 2}O{sub 3} thin coatings for corrosion protection of steel: Surface and electrochemical analysis

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, Belen [Laboratoire de Physico-Chimie des Surfaces, CNRS (UMR 7045) - Chimie-ParisTech (ENSCP), 11 rue Pierre et Marie Curie, F-75005 Paris (France); Haerkoenen, Emma [Laboratory of Inorganic Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki (Finland); Swiatowska, Jolanta [Laboratoire de Physico-Chimie des Surfaces, CNRS (UMR 7045) - Chimie-ParisTech (ENSCP), 11 rue Pierre et Marie Curie, F-75005 Paris (France); Maurice, Vincent, E-mail: vincent-maurice@chimie-paristech.f [Laboratoire de Physico-Chimie des Surfaces, CNRS (UMR 7045) - Chimie-ParisTech (ENSCP), 11 rue Pierre et Marie Curie, F-75005 Paris (France); Seyeux, Antoine [Laboratoire de Physico-Chimie des Surfaces, CNRS (UMR 7045) - Chimie-ParisTech (ENSCP), 11 rue Pierre et Marie Curie, F-75005 Paris (France); Marcus, Philippe, E-mail: philippe-marcus@chimie-paristech.f [Laboratoire de Physico-Chimie des Surfaces, CNRS (UMR 7045) - Chimie-ParisTech (ENSCP), 11 rue Pierre et Marie Curie, F-75005 Paris (France); Ritala, Mikko, E-mail: Mikko.Ritala@Helsinki.f [Laboratory of Inorganic Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki (Finland)

    2011-06-15

    Highlights: {yields} 10-100 nm Alumina coatings grown by ALD at 160 {sup o}C for protection of steel. {yields} Al{sub 2}O{sub 3} stoichiometry of the coating and trace contamination by growth precursors. {yields} Iron oxide and siloxane presence at the buried coating/steel interface. {yields} Exponential decay of coating porosity over four orders of magnitude with thickness increase. {yields} Coating thickness increase required to seal the defective first deposited 10 nm. - Abstract: ToF-SIMS, XPS, voltammetry and EIS investigation of the anti-corrosion properties of thin (10, 50 and 100 nm) alumina coatings grown by atomic layer deposition at 160 {sup o}C on steel is reported. Surface analysis shows a thickness-independent Al{sub 2}O{sub 3} stoichiometry of the coating and trace contamination by the growth precursors. The buried coating/alloy interface has iron oxide formed in ambient air and/or resulting from the growth of spurious traces in the initial stages of deposition. Electrochemical analysis yields an exponential decay of the coating porosity over four orders of magnitude with increasing thickness, achieved by sealing of the more defective first deposited 10 nm.

  9. Corrosion protection at Crimean NPP

    International Nuclear Information System (INIS)

    Coal-epoxide compositions modified by adsorption-active additions as well as reinforced coatings of the same type for pipeline protection against soil corrosion are investigated to provide for corrosion protection of water-supply systems at the Crimean NPP. Laboratory test in the Asov Sea water at 50-90 deg C confirmed the reliability of the coatings proposed. Works on NPP pipeline protection are performed using the coatings recommended which appeared to be quite efficient for construction and assemling works and as a result of corrosion prevention a sufficient economic effect (1.16 millions of roubles) is abtained

  10. Corrosion protection of 13CrMo 44 heat-resistant ferritic steel by silicon and cerium ion implantation for high-temperature applications

    Energy Technology Data Exchange (ETDEWEB)

    Perez, F.J.; Otero, E.; Hierro, M.P.; Gomez, C.; Pedraza, F. [Universidad Complutense de Madrid (Spain). Dept. de Ciencia de los Materiales; Segovia, J.L. de [Consejo Superior de Investigaciones Cientificas, Inst. Torres Quevedo, Madrid (Spain); Roman, E. [Consejo Superior de Investigaciones Cientificas, Inst. de Ciencia de los Materiales, Canto Blanco, Madrid (Spain)

    1998-10-10

    The influence of the ion implantation of 1 x 10{sup 15} ions/cm{sup 2} of silicon and 1 x 10{sup 14} ions/cm{sup 2} of cerium at 150 keV on the oxidation behaviour of a 0.80%Cr-0.40%Mo heat-resistant 13CrMo 44 ferritic steel was studied at 973 K in air for 144 h under isothermal conditions. The implanted surfaces and the corrosion products formed on the surface were characterized by means of AES, SEM and XRD. Theoretical calculations were performed by TRIM96 computational code. From the present study it was concluded that silicon enhances selective oxidation of chromium and a more protective oxide scale was found to grow. However, cerium confers a detrimental effect by cracking and spalling of the oxide layers formed at high temperature. (orig.) 13 refs.

  11. Characterization of iron oxides and atmospheric corrosion of steel

    Science.gov (United States)

    Oh, Sei Jin

    Research has been performed on steel coupons exposed to the atmosphere in order to improve the understanding of the formation and development of iron oxides which control atmospheric corrosion, and to establish data for predicting corrosion behavior taking place under specific atmospheric conditions. Improving the analytical techniques required for studying corrosion behavior was another goal of this research. Then, different analytical techniques can provide additional information, such as identification, fractions and layering of iron oxides formed on steels. The study of corrosion behavior was performed using three different analytical techniques, which provided information on the formation, development and layering of iron oxides on the corrosion products as a function of atmospheric conditions, exposure time and type of steel. In particular, the protective layer formed on weathering steel was investigated as a function of different amounts of alloying elements in the steel, atmospheric conditions and exposure times. Combined together, the results provided a better understanding of the atmospheric corrosion behavior of steel, and formed a part of database of the atmospheric corrosion characteristics. Accurate characterization of the iron oxides often formed on steel surfaces was one of the aims for this research. Seven iron oxides, goethite (?-FeOOH), akaganeite (?-FeOOH), lepidocrocite (?-FeOOH), ?-FeOOH, hematite (/alpha- F2O3), maghemite (?- F2O3) and magnetite (F3O4), which are often found in corrosion products present on steel, were characterized by Mossbauer spectroscopy, Raman spectrometry and x-ray diffraction analysis. Complete identification of the corrosion products formed on steel required more than one and most often three of the analytical techniques. In particular, the Mossbauer characterization of the iron oxides included measuring the relative recoilless fraction (F-value), which was defined as the ratio of recoil-free fractions of two different materials. The relative recoilless fractions of the iron oxides allowed the conversion of Mossbauer subspectral areas to the relative atomic, molecular, or weight fraction of each present in a mixed iron oxide sample. The characterization of the iron oxides was used to study the atmospheric corrosion behavior of weathering, copper bearing and carbon steels as a function of environmental condition, exposure time and type of steel. Goethite, akaganeite, lepidocrocite, maghemite and magnetite were identified in the corrosion products formed on the steel coupons. The formation of superparamagnetic goethite showed a correlation with the corrosion rate for seven types of steels. After long term exposure, superparamagnetic goethite on weathering steel, was the final iron oxide formed in the corrosion products. The conosion products typically formed in two layers. The protective layer, the inner layer, was formed by goethite and superparamagnetic maghemite. Increased amounts silicon and smaller amounts of phosphorus in the steel substrate increased the relative fraction of superparamagnetic goethite, in marine and rural environments. However, different amounts of nickel did not affect the formation of the iron oxides even after long term exposure. Increasing the silicon content in steel would be helpful in enhancing corrosion resistance for the long term lifetime of steel structures under atmospheric conditions.

  12. Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    2000-01-01

    carbon steel must be monitored on-line in order to provide an efficient protection and control the corrosion. A number of monitoring techniques is industrially used today, and the applicability and reliability of these for monitoring MIC is evaluated. Coupons and ER are recommended as necessary basic...... initiates localised corrosion on the anode and seems applicable to evaluate the risk of MIC. Hydrogen permeation measurements are very useful to monitor hydrogen induced cracking accelerated by MIC.......Abstract Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel Microbially influenced corrosion (MIC) of carbon steel may occur in media with microbiological activity of especially sulphate-reducing bacteria, e.g. on pipelines buried in soil and on marine structures. MIC of...

  13. Corrosion of Electrogalvanized Steel in 0.1 M NaCl Studied by SVET

    OpenAIRE

    Bastos, A. C.; Simões, A. M.; Ferreira, M.G.

    2003-01-01

    The corrosion of electrogalvanized steel exposed to 0.1 M NaCl was studied using the SVET. Situations of localized corrosion, cathodic protection and corrosion protection due to surface pre-treatment were analyzed, putting in evidence the possibilities of the technique.

  14. Corrosion of Electrogalvanized Steel in 0.1 M NaCl Studied by SVET

    Directory of Open Access Journals (Sweden)

    A.C. Bastos

    2003-01-01

    Full Text Available The corrosion of electrogalvanized steel exposed to 0.1 M NaCl was studied using the SVET. Situations of localized corrosion, cathodic protection and corrosion protection due to surface pre-treatment were analyzed, putting in evidence the possibilities of the technique.

  15. The Corrosion of High Performance Steel in Adverse Environments

    International Nuclear Information System (INIS)

    The corrosion products that have formed on weathering steel bridges exposed to different weather conditions in the United States have been evaluated. They have been analyzed by spectroscopic techniques to determine the relationship between protective and non-protective rust coatings, and their relationship to the exposure conditions. Bridges constructed recently using High Performance Steel, as well as older bridges built with Type A588B weathering steel, were evaluated for corrosion performance of the rust coatings. In locations where the steel is subjected to regular wet-dry cycling, where the surface is wet for less than about 20% of the time, a protective patina starts to form after a few months exposure, and continues to an adherent, impervious coating after a decade. The protective patina is characterized by the formation of only goethite and lepidocrocite. The goethite makes up about 80% of the rust, and itself consists of a nanophase component, 40%, or infrequent drying cycles (regions close to waterways, fog or having high humidity), the weathering steel forms a rust coating that consists of a large amount of maghemite, and goethite that contains very little of the nanophase component. The rust coating ex-foliates from the steel and is not protective. Under exposure conditions in which chlorides are deposited onto the weathering steel surface (marine or de-icing salt locations), the protective patina also does not form. Instead, the rust coating consists of a large fraction of akaganeite that forms at the expense of the lepidocrocite and nanophase goethite. The bridges exposed to high chloride concentrations, 1.5 wt%, and therefore having no protective patina, have corrosion rates measured to be 6 times larger than expected for weathering steel with the protective patina

  16. Corrosion-protective coatings from electrically conducting polymers

    Science.gov (United States)

    Thompson, Karen Gebert; Bryan, Coleman J.; Benicewicz, Brian C.; Wrobleski, Debra A.

    1991-01-01

    In a joint effort between NASA Kennedy and LANL, electrically conductive polymer coatings were developed as corrosion protective coatings for metal surfaces. At NASA Kennedy, the launch environment consist of marine, severe solar, and intermittent high acid and/or elevated temperature conditions. Electrically conductive polymer coatings were developed which impart corrosion resistance to mild steel when exposed to saline and acidic environments. Such coatings also seem to promote corrosion resistance in areas of mild steel where scratches exist in the protective coating. Such coatings appear promising for many commercial applications.

  17. Localized Corrosion of Chromium Coated Steel :

    OpenAIRE

    Zhang, X.; Beentjes, P.; Mol, A.; Terryn, H.

    2006-01-01

    In this paper, we report on the studies of the local corrosion behaviour of chromium-coated ultra low carbon steel in NaCl solution using polarization, electrochemical impedance spectroscopy (EIS) and SVET.

  18. Hot corrosion of pack cementation aluminized carbon steel

    International Nuclear Information System (INIS)

    Low carbon steel was aluminized by the pack cementation technique at various aluminizing temperatures and times in or der to have different aluminide coatings. The aluminized specimens were sprayed at the beginning of the hot corrosion experiments with Na C 1+Na2 SO4 solution. The hot corrosion tests were carried out by thermal cycling at 850 degree C in air. The results were evaluated by, corrosion kinetics based on weight change measurements, scanning electron microscopy and energy dispersive X-ray analysis. It was found that the maximum corrosion resistance to this corrosive environment is achieved by aluminizing at 900 degree C for 19 h or 950 degree C for >4 h. These aliminizing conditions lead to formation of thick aluminide coatings with sufficient aluminium concentration (>15 wt%) at their outer surface necessary for continuous formation of protective Al2 O3 scale. The tested materials are used in protection of some components used in electric power stations (conventional or nuclear)

  19. Stainless steel acid corrosion inhibition by organic dyes

    International Nuclear Information System (INIS)

    Azobenzene dyes are effective inhibitors for austenitic 304 L and 316 L stainless steel corrosion in high acidic medium up to 7N. A good efficiency is obtained from weight loss and electrochemical Rsub(p) measurements in hydrochloric acid, while no inhibition is observed in sulfuric solutions. Transformation from the primarily azobenzene to other compounds give rise to enhanced protection of steel samples, and probable structures of the inhibiting species are proposed in view of our results

  20. Corrosion of an austenite and ferrite stainless steel weld

    Directory of Open Access Journals (Sweden)

    BRANIMIR N. GRGUR

    2011-07-01

    Full Text Available Dissimilar metal connections are prone to frequent failures. These failures are attributed to the difference in the mechanical properties across the weld, the coefficients of thermal expansion of the two types of steels and the resulting creep at the interface. For the weld analyzed in this research, it was shown that corrosion measurements can be used for a proper evaluation of the quality of weld material and for the prediction of whether or not the material, after the applied welding process, can be in service without failures. It was found that the corrosion of the weld analyzed in this research resulted from the simultaneous activity of different types of corrosion. In this study, electrochemical techniques including polarization and metallographic analysis were used to analyze the corrosion of a weld material of ferrite and austenitic stainless steels. Based on surface, chemical and electrochemical analyses, it was concluded that corrosion occurrence was the result of the simultaneous activity of contact corrosion (ferrite and austenitic material conjuction, stress corrosion (originating from deformed ferrite structure and inter-granular corrosion (due to chromium carbide precipitation. The value of corrosion potential of –0.53 V shows that this weld, after the thermal treatment, is not able to repassivate a protective oxide film.

  1. Corrosion Properties of Laser Welded Stainless Steel

    DEFF Research Database (Denmark)

    Weldingh, Jakob; Olsen, Flemmming Ove

    In this paper the corrosion properties of laser welded AISI 316L stainless steel are examined. A number of different welds has been performed to test the influence of the weld parameters of the resulting corrosion properties. It has been chosen to use the potential independent critical pitting...... temperature (CPT) test as corrosion test. The following welding parameters are varied: Welding speed, lsser power, focus point position and laser operation mode (CW or pulsed)....

  2. Corrosion of Steel in Concrete – Potential Monitoring and Electrochemical Impedance Spectroscopy during Corrosion Initiation and Propagation

    DEFF Research Database (Denmark)

    Küter, Andre; Mason, Thomas O.; Geiker, Mette Rica; Møller, Per

    investigation on the effect of the steel quality and the steel surface properties on initiation and propagation of chloride-induced reinforcement corrosion. Besides untreated (as received) carbon rebars and stainless rebars, selected surface treatments and galvanization were investigated. The surface treatments...... rebar appears to be protected throughout the experimental period to date (200 days), whereas active corrosion of the stainless steel appeared to be initiated after 100 days exposure....

  3. SYNERGIC MIXTURES PROTECTIVE ACTION AS THE FUNCTION OF WATER-SALINE MEDIUM COMPONENTS NATURE AND RATIO OF ITS CONCENTRATIONS AT CORROSION OF STEEL

    OpenAIRE

    ?????????, ????????? ??????????; ????????, ?????? ?????????????

    2012-01-01

    The relation between the ratio of concentrations of components in binary mixtures of adsorption and passivation effects inhibitors; its influence on the corrosion-electrochemical behavior in aqueous salt mediums (method of isomolar series) was studied. It was shown that this effect has an extremum character, where the most corrosion inhibition of anodic reaction is achieved at synergistic maximum where also achieved almost complete corrosion protection.

  4. Development of novel protective high temperature coatings on heat exchanger steels and their corrosion resistance in simulated coal firing environment; Developpement de revetements pour les aciers d'echangeurs thermiques et amelioration de leur resistance a la corrosion en environnement simulant les fumees de combustion et de charbon

    Energy Technology Data Exchange (ETDEWEB)

    Rohr, V.

    2005-10-15

    Improving the efficiencies of thermal power plants requires an increase of the operating temperatures and thus of the corrosion resistance of heat exchanger materials. Therefore, the present study aimed at developing protective coatings using the pack cementation process. Two types of heat exchanger steels were investigated: a 17% Cr-13% Ni austenitic steel and three ferritic-martensitic steels with 9 (P91 and P92) and 12% Cr (HCM12A). The austenitic steel was successfully aluminized at 950 C. For the ferritic-martensitic steels, the pack cementation temperature was decreased down to 650 C, in order to maintain their initial microstructure. Two types of aluminides, made of Fe{sub 2}Al{sub 5} and FeAl, were developed. A mechanism of the coating formation at low temperature is proposed. Furthermore, combining the pack cementation with the conventional heat treatment of P91 allowed to take benefit of higher temperatures for the deposition of a two-step Cr+Al coating. The corrosion resistance of coated and uncoated steels is compared in simulated coal firing environment for durations up to 2000 h between 650 and 700 C. It is shown that the coatings offer a significant corrosion protection and, thus, an increase of the component lifetime. Finally, the performance of coated 9-12% Cr steels is no longer limited by corrosion but by interdiffusion between the coating and the substrate. (author)

  5. Electrochemical study of polypyrrole/PW12O-340 coatings on carbon steel electrodes as protection against corrosion in chloride aqueous solutions

    OpenAIRE

    Bonastre Cano, José Antonio; Garcés Terradillos, Pedro; Huerta Arráez, Francisco; Quijada Tomás, César; García Andión, Luis; Cases Iborra, Francisco Javier

    2005-01-01

    Hybrid material polypyrrole/PW12O-340 was electrosynthesised on carbon steel electrodes in acetonitrile medium. Passivation pretreatment of carbon steel in acetonitrile/perchlorate medium was used to avoid electrodissolution of electrode during the polymerisation. These hybrid coatings were evaluated against corrosion in chloride-containing 0.05 M NaOH and solutions obtained by ?ltering Portland cement slurries. Cyclic voltammetry, polarisation resistance(Rp), and Fe2+ concentrations me...

  6. Rust and corrosion resistant cast steel

    International Nuclear Information System (INIS)

    An austenite-ferritic chromium-nickel (molybdenum) steel alloy is used to manufacture rust and corrosion-resistant, weldable casting steel without thermal treatment. The alloy exhibits a minimum yield strength of 35-45 kg/mm2 and tensile strength of between 55-65 kg/mm2 depending on the ferrite content. (IHOE)

  7. Atmospheric corrosion of mild steel. Pt. I. Rural and urban atmospheres

    International Nuclear Information System (INIS)

    This paper summarizes the results obtained in the MICAT project for mild steel specimens exposed for 1 to 4 years in 22 rural and urban atmospheres in the Ibero-American region. Test site characterization and chemical and morphological determination of the steel corrosion product layers (SCPLs) contributed to understanding the corrosion phenomena involved. It was observed how some climatological factors could affect steel corrosion rates and SCPL properties. Although the studied atmospheres were classified into different ISO groups, steel corrosion rates did not differ significantly between them. The only common characteristic of these atmospheres was an increase in SCPLs protectiveness with exposure time. (orig.)

  8. Corrosion behavior of carbon steel in wet Na-bentonite medium

    International Nuclear Information System (INIS)

    Corrosion behaviors of carbon steel in wet Na-bentonite medium were studied. Corrosion rate of carbon steel in wet bentonite was measured to be 20 ?m/yr at 25 deg C using the AC impedance technique. This value is agreed with that obtained by weight loss at 40 deg C for 1 year. The effect of bicarbonate ion on the corrosion of carbon steel in wet bentonite was also evaluated. The carbon steels in wet bentonite having 0.001, 0.01, and 0.1 M concentration of bicarbonate ion gave corrosion rates of 20, 8, and 0.2 ?m/yr, respectively. Corrosion potentials of specimens were also measured and compared with the AC impedance results. Both results indicated that bicarbonate ion could effectively reduce the corrosion rate of carbon steels in bentonite due to the formation of protective layer on the carbon steel. (author)

  9. Prevention of Crevice Corrosion of STS 304 Stainless Steel by a Mg-alloy Galvanic Anode

    International Nuclear Information System (INIS)

    Prevention of crevice corrosion was studied for STS 304 stainless steel using a Mg-alloy galvanic anode in solutions with various specific resistivity. The crevice corrosion and corrosion protection characteristics of the steel was investigated by the electrochemical polarization and galvanic corrosion tests. Experimental results show that the crevice corrosion of STS 304 stainless steel does not occur in solutions of high specific resistivity, but it occurs in solutions of low specific resistivity like in solutions with resistivities of 30, 60 and 115 ? · m. With decreasing specific resistivity of the solution, the electrode potential of STS 304 stainless steel in the crevice is lowered. The potential of STS 304 stainless steel in the crevice after coupling is cathodically polarized more by decreasing specific resistivity indicating that the crevice corrosion of STS 304 stainless steel is prevented by the Mg-alloy galvanic anode

  10. Marine atmospheric corrosion of carbon steels

    International Nuclear Information System (INIS)

    Basic research on marine atmospheric corrosion of carbon steels is a relatively young scientific field and there continue to be great gaps in this area of knowledge. The presence of akaganeite in the corrosion products that form on steel when it is exposed to marine atmospheres leads to a notable increase in the corrosion rate. This work addresses the following issues: (a) environmental conditions necessary for akaganeite formation; (b) characterisation of akaganeite in the corrosion products formed; (c) corrosion mechanisms of carbon steel in marine atmospheres; (d) exfoliation of rust layers formed in highly aggressive marine atmospheres; (e) long-term corrosion rate prediction; and (f) behaviour of weathering steels. Field research has been carried out at Cabo Vilano wind farm (Camarinas, Galicia) in a wide range of atmospheric salinities and laboratory work involving the use of conventional atmospheric corrosion techniques and near-surface and bulk sensitive analytical techniques: scanning electron microscopy (SEM)/energy dispersive spectrometry (EDS), X-ray diffraction (XRD), Mossbauer spectroscopy and SEM/?Raman spectroscopy. (Author)

  11. Marine atmospheric corrosion of carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    Morcillo, M.; Alcantara, J.; Diaz, I.; Chico, B.; Simancas, J.; Fuente, D. de la

    2015-07-01

    Basic research on marine atmospheric corrosion of carbon steels is a relatively young scientific field and there continue to be great gaps in this area of knowledge. The presence of akaganeite in the corrosion products that form on steel when it is exposed to marine atmospheres leads to a notable increase in the corrosion rate. This work addresses the following issues: (a) environmental conditions necessary for akaganeite formation; (b) characterisation of akaganeite in the corrosion products formed; (c) corrosion mechanisms of carbon steel in marine atmospheres; (d) exfoliation of rust layers formed in highly aggressive marine atmospheres; (e) long-term corrosion rate prediction; and (f) behaviour of weathering steels. Field research has been carried out at Cabo Vilano wind farm (Camarinas, Galicia) in a wide range of atmospheric salinities and laboratory work involving the use of conventional atmospheric corrosion techniques and near-surface and bulk sensitive analytical techniques: scanning electron microscopy (SEM)/energy dispersive spectrometry (EDS), X-ray diffraction (XRD), Mossbauer spectroscopy and SEM/?Raman spectroscopy. (Author)

  12. Corrosion behaviour of solution nitrided stainless steels

    International Nuclear Information System (INIS)

    The case of near net shape parts made from austenitic steel X2CrNiMo17-13-2 and austenitic-ferritic steels X2CrNiMoN22-5-3 (wrought) and G-X3CrNiMoCuN26-6-3-3 (cast) is interstitially enriched with nitrogen by the diffusion-based process ''solution nitriding''. In order to obtain good corrosion resistance and mechanical properties, the solution nitriding parameters and the applied cooling time are selected so, that precipitates are avoided (X2CrNiMo17-13-2, X2CrNiMoN22-5-3). However, in case of a superimposed hydroabrasive load, the presence of nitrides in the case is found to be beneficial. The solution nitrided and the solution annealed conditions of the steels are compared with respect to their susceptibility to corrosion by means of electrochemical polarisation curves. The erosion corrosion behaviour of the materials is analysed in pilot scale flow-loop tests using particle loaded corrosive and particle loaded non-corrosive media. It is shown that ''solution nitriding'' leads to improved corrosion behaviour and/or improved erosion corrosion resistance, in particular in the case of the duplex steels. (orig.)

  13. Stress corrosion of low alloy steel forgings

    International Nuclear Information System (INIS)

    The catastrophic failure of a steam turbine rotor disc at Hinkley Point 'A' Power station was shown to have been caused by the growth of a stress corrosion crack to critical dimensions. This failure has promoted great interest in the stress corrosion susceptibility of medium strength low alloy steel forgings in steam environments. Consequently, initiation and growth of stress corrosion cracks of typical disc steels have been investigated in steam and also in water at 950C. Cracking has been shown to occur, predominantly in an intergranular manner, with growth rates of between 10-9 and 10-7 mm sec.-1. It is observed that corrosion pitting and oxide penetration prior to the establishment of a stress corrosion crack in the plain samples. (author)

  14. Corrosion inhibition properties of TTA and phosphate on copper and stainless steel

    International Nuclear Information System (INIS)

    Based on the corrosion issue of cooling water system containing copper, the corrosion inhibition properties and protection mechanism of inhibition on copper and stainless steel were studied by performing the electrochemical test, immersion test and dynamic water simulation test. The results show that corrosion inhibitors have excellent corrosion inhibition efficiency on copper in the condition of either pure water or harsh water. The optimum inhibitor is the compound consisting of TTA and sodium orthophosphate. At the same time, the corrosion inhibitor elevates the breakdown potential of stainless steel and contributes to the enhancement of corrosion resistance. (authors)

  15. Structural factors conditioned steel stability under cavitation in corrosive environment

    International Nuclear Information System (INIS)

    The effect of cavitation on chromium steel 95Kh18, chromium-nickel steel 12Kh18N9T and maraging steel 03Kh10N5K5M3DTYuS is studied. The relation between the martensite content in steel and corrosion and cavitation stability is traced. It is shown that under static conditions corrosion is related to martensite dissolution, while cavitation-corrosion stability is higher for steels with higher martensite content. The conclusion is made that maraging steels are characterized by high corrosion stability, as well as high cavitation corrosion resistance, and they are recommended for application in static and dynamic contacts with corrosive environments

  16. Cathodic protection of steel framed masonry structures - experimental and numerical studies

    OpenAIRE

    Lambert, Paul; Mangat, Pal; O'Flaherty, Fin; Wu, You-Yo

    2008-01-01

    Many high-profile steel-framed masonry buildings are susceptible to extensive damage as a result of corrosion of the steel frame. This has resulted in serious consequences with respect to serviceability, safety, aesthetics and heritage. Cathodic protection (CP) is a proven method for preventing and protecting buried and submerged steel and reinforced concrete structures from corrosion. More recently, the method has been introduced to prevent and control corrosion in steel-framed masonry struc...

  17. Conducting polyaniline/multi-wall carbon nanotubes composite paints on low carbon steel for corrosion protection: electrochemical investigations.

    Czech Academy of Sciences Publication Activity Database

    Deshpande, P. P.; Vathare, S. S.; Vagge, S. T.; Tomšík, Elena; Stejskal, Jaroslav

    2013-01-01

    Ro?. 67, ?. 8 (2013), s. 1072-1078. ISSN 0366-6352 R&D Projects: GA ?R GA202/09/1626 Institutional support: RVO:61389013 Keywords : corrosion * polyaniline * conducting polymer Subject RIV: JI - Composite Materials Impact factor: 1.193, year: 2013

  18. Metallic corrosion of steels embedded in calcium aluminate cement mortars

    OpenAIRE

    García Andión, Luis; Garcés Terradillos, Pedro; Cases Iborra, Francisco Javier; García Andreu, César; Vázquez Picó, José Luis

    2001-01-01

    In the present paper, the corrosion levels of reinforcing steels embedded in Calcium Aluminate Cement (CAC) mortars have been studied. Experiments were designed to investigate the influence of the following factors in steel corrosion: cover thickness, type of steel (carbon steel (CS) and stainless steel (SS)), temperature at mixing and curing, influence of chloride concentration, nitrite ion as corrosion inhibitor and carbonation of mortar. The reinforcing steel bars do not become more corrod...

  19. Air crevice corrosion of stainless steels

    International Nuclear Information System (INIS)

    Test structures were used to study crevice corrosion of stainless steels, including high-strength ones, in salt fog. Test results enabled to range stainless steels according to their resistance to crevice corrosion in air: resistant steels-12Kh18N10T, 08Kh15N5D2T, 06Kh14N6D2MBT, 13Kh15N4AM3, 08Kh17N5AM3; low-resistant steels - 03Kh10N11M2T, 03Kh12N10MT, 03Kh9N9K5M3, 15Kh16N2AM; nonresistant steels -13Kh11N2V2MF, 20Kh13, 40Kh13, 95Kh18. 19 refs.; 5 tabs

  20. Crevice Corrosion of 321 Stainless Steel in Sodium Chloride Solutions

    International Nuclear Information System (INIS)

    Electrochemical techniques have been applied to study the crevice corrosion behaviour of stabilized 321 stainless steel in both 0.5, 1 and 2 M sodium chloride solutions at 25 and 80 degree . This type of stainless steel enjoys a good corrosion resistance especially in the heat affected zone (Haz) of welds. In this investigation the crevice corrosion of 321 stainless steel was studied in both bulk solution environments as well as in chloride solutions simulating those formed inside crevices. A metal-to-nonmetal crevice assembly, in which disc type specimens were faced to a PTFE crevice former, is used for bulk solution tests. Crevice-free specimens of solutions formed inside crevices (known as the critical crevice solutions, CCS). Cyclic potentiodynamic technique was used in evaluating the electrochemical corrosion performance of the alloy in bulk (0.5 and 1 M Nacl) environment. This revealed that both chloride ion concentration and temperature have a marked effect on the electrochemical parameters generally used for the evaluation of the crevice corrosion susceptibility. This included the corrosion potential. E corr. The passivity breakdown potential, Eb, and the protection potential, E p

  1. Research on atmospheric corrosion of steel using synchrotron radiation

    International Nuclear Information System (INIS)

    Correlation between local structure around Cr in the protective rust layer on weathering steel and protective performance of the rust layer is presented as an example of corrosion research using synchrotron radiation which has recently been applied in various research fields as a useful tool. In addition, in situ observation of initial process of rust formation on steel is also mentioned. It was pointed out by considering the X-ray absorption fine structure spectra that the nanostructure of the protective rust layer on weathering steel primarily comprises of small Cr-goethite crystals containing surface adsorbed and/or intergranular CrOx3-2X complex anions. This CrOx3-2X explains the protective performance of the rust layer originated by dense aggregation of fine crystals with cation selectivity of the Cr-goethite. It is very advantageous to employ white X-rays for in situ observation of rusting process of a carbon steel covered with electrolyte thin films because rust structure might change very quickly. This in situ observation revealed the effect of ion species on the change in rust phase during wet/dry repeating. It can be said that application of synchrotron radiation on corrosion research is so useful to understand the nanostructure of surface oxides which closely relate to corrosion behavior of metals and alloys. (author)

  2. POLYETHERSULFONE COATING FOR MITIGATING CORROSION OF STEEL IN GEOTHERMAL ENVIRONMENT.

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA, T.

    2005-06-01

    Emphasis was directed toward evaluating the usefulness of a polyethersulfone (PES)-dissolved N-methyl pyrrolidone (NMP) solvent precursor as a low-temperature film-forming anti-corrosion coating for carbon steel in simulated geothermal environments at brine temperatures up to 300 C. A {approx} 75 {micro}m thick PES coating performed well in protecting the steel against corrosion in brine at 200 C. However, at {>=} 250 C, the PES underwent severe hydrothermal oxidation that caused the cleavage of sulfone- and ether-linkages, and the opening of phenyl rings. These, in turn, led to sulfone {yields} benzosulfonic acid and ether {yields} benzophenol-type oxidation derivative transformations, and the formation of carbonyl-attached open rings, thereby resulting in the incorporation of the functional groups, hydroxyl and carbonyl, into the coating. The presence of these functional groups raised concerns about the diminutions in water-shedding and water-repellent properties that are important properties of the anti-corrosion coatings; such changes were reflected in an enhancement of the magnitude of susceptibility of the coatings surfaces to moisture. Consequently, the disintegration of the PES structure by hydrothermal oxidation was detrimental to the maximum efficacy of the coating in protecting the steel against corrosion, allowing the corrosive electrolytes to infiltrate easily through it.

  3. Corrosion and deposition of corrosion products on carbon steel and martensitic steel components of CANDU-6 reactor primary circuit

    International Nuclear Information System (INIS)

    Cernavoda NPP Unit 1 is a heavy water cooled and moderated CANDU 6 reactor, using natural uranium as fuel. To ensure a minimal degradation of structural materials by fluid contact and to achieve or exceed the design lifetime of the plant, a chemical control and corrosion monitoring program has been established. The corrosion of the Primary Heat Transport System (PHTS) components is minimized by carefully selecting and then controlling a set of chemical parameters to reduce the aggressiveness of the coolant to specific metals used in the system. Chemical control of PHTS and surveillance of structural materials corrosion is directed towards keeping chemical parameters within specified limits in order to minimize corrosion of equipment and related piping, to control the corrosion rate, impurities concentration and fission products and to minimize activity transport and heat transfer surfaces fouling. To monitor the effects of operating chemistry on the corrosion of the system's components and the build-up of activity on construction materials and to show up important effects in the activity transport, an Autoclave System is required. To determine corrosion and to characterize the superficial oxide films formed on carbon and martensitic steel, the following methods have been used: gravimetric, metallographic and electronic microscopy, electrochemical impedance spectroscopy (EIS), X-ray diffraction and XPS. The analysis of the samples exposed for different times in autoclaves (197, 371, 568 and 825 days), allowed us to determine the corrosion rate, the deposition and releasing of corrosion products, as well as the characteristics of the corrosive films formed. The results obtained by corrosion analysis of the carbon and martensitic steel coupons exposed in Y1-Y4 autoclaves, assembled in by-pass of CANDU-6 reactor primary circuit from Cernavoda NPP Unit 1 showed the following: - The continuous, adherent and protective oxide films were formed by generalized corrosion of structural materials. By increasing the exposure times better formation of more adherent oxides was evidenced but not any localized corrosion. The corrosion products were mainly magnetite crystalides. Their quantity increased with exposure time and was higher on samples exposed in autoclave circuits in the reactor inlet header, because the magnetite solubility is smaller, the temperature being smaller, and the coolant is probably still supersaturated in iron. The corrosion products release rate and the corrosion rate for carbon steel SA 106 gr.B decreased, while the exposure time increased. The higher values for these rates, especially at the beginning, were obtained on the samples exposed in autoclave circuits from the reactor inlet header

  4. Corrosion of steel tendons used in prestressed concrete pressure vessels

    International Nuclear Information System (INIS)

    The purpose of this investigation was to determine the corrosion behavior of a high strength steel (ASTM A416-74 grade 270), typical of those used as tensioning tendons in prestressed concrete pressure vessels, in several corrosive environments and to demonstrate the protection afforded by coating the steel with either of two commercial petroleum-base greases or Portland Cement grout. In addition, the few reported incidents of prestressing steel failures in concrete pressure vessels used for containment of nuclear reactors are reviewed. The susceptibility of the steel to stress corrosion cracking and hydrogen embrittlement and its general corrosion rate were determined in several salt solutions. Wires coated with the greases and grout were soaked for long periods in the same solutions and changes in their mechanical properties were subsequently determined. All three coatings appeared to give essentially complete protection but small flaws in the grease coatings were detrimental; flaws or cracks less than 1 mm wide in the grout were without effect

  5. Corrosion behavior of novel 3%Cr pipeline steel in CO2 Top-of-Line Corrosion environment

    International Nuclear Information System (INIS)

    Highlights: ? CO2 Top-of-Line Corrosion environment in wet gas pipelines was simulated. ? Compared with X70, the resistance to CO2 TLC of novel 3%Cr pipeline steel is better. ? The effect of Cr enrichment in the corrosion scale on CO2 TLC is confirmed. -- Abstract: CO2 Top-of-Line Corrosion (TLC) of carbon steel pipelines is a serious problem for wet gas transportation. We have studied the corrosion behavior of novel 3%Cr (3Cr) pipeline steel and conventional carbon steel (X70) in the simulated CO2 TLC environment. The composition and morphology of the corrosion scale are characterized by X-ray diffraction, energy dispersive X-ray spectroscopy and scanning electron microscopy analyses. The results indicate that 3Cr pipeline steel shows superior resistance to CO2 TLC, exhibiting uniform corrosion with duplex corrosion layer, while X70 suffers severe localized corrosion. It was suggested that the inner Cr enriched layer enhanced the protective ability of the scale to steel substrate and improved the resistance to localized corrosion in CO2 TLC environment.

  6. Corrosion of Steels in Steel Reinforced Concrete in Cassava Juice

    Science.gov (United States)

    Oluwadare, G. O.; Agbaje, O.

    The corrosion of two types of construction steels, ST60Mn and RST37-2?, in a low cyanide concentration environment (cassava juice) and embedded in concrete had been studied. The ST60 Mn was found to be more corrosion resistant in both ordinary water and the cassava juice environment. The cyanide in cassava juice does not attack the steel but it provides an environment of lower pH around the steel in the concrete which leads to breakdown of the passivating film provided by hydroxyl ions from cement. Other factors such as the curing time of the concrete also affect the corrosion rates of the steel in the concrete. The corrosion rate of the steel directly exposed to cassava juice i.e., steel not embedded in concrete is about twice that in concrete. Long exposure of concrete structure to cassava processing effluent might result in deterioration of such structures. Careful attention should therefore be paid to disposal of cassava processing effluents, especially in a country like Nigeria where such processing is now on the increase.

  7. Corrosion of steel in ionic liquids

    OpenAIRE

    Arenas M.F.; Reddy R.G.

    2003-01-01

    The corrosion behavior of 1018 carbon steel alloy has been investigated by electrochemical techniques. The ionic liquids studied were 1-butyl-3-methylimidazolium chloride ([C4mim]Cl), 1 hexyl-3-methylimidazolium hexafluorophosphate ([C6mim]PF6) 1-octyl-3-methylimidazolium hexafluorophosphate ([C8mim]PF6), and 1-butyl-3-methylimidazolium bis-(trifluoromethanesulfonyl) imide ([C4mim][Tf2N]). Potentiodynamic polarization and Tafel plots were used to determine the corrosion behavior of the carbon...

  8. Alternating Current Corrosion of Carbon Steel

    OpenAIRE

    Belland, Eirik

    2011-01-01

    The objective was to investigate if the established theory concerning corrosion calculations and electrochemical behavior of carbon is valid when steel is exposed to AC in an electrolyte consisting of 3,5 wt% NaCl and distilled water. The experimental work was divided in two main parts. The first part concerned corrosion testing, including weight loss measurements in stagnant conditions in combination with linear polarization resistance experiments. AC-current densities investigated was 0-, 5...

  9. Diamond smoothing effect on chloride corrosion cracking resistance of Kh17N15 steel

    International Nuclear Information System (INIS)

    Results of investigation into effect of the surface plastic deformation of metal using diamond smothing method on resistance of Kh17N15 steel to chloride corrosion cracking are presented. Peculiarities of thin-wall article treatment, effect of smothing conditions and conditions of steel charging for electrochemical and corrosion behaviour in high parameter chloride-containing water, are discussed. Application perspective of diamond smothing to protect articles working under loads lower than the conventional yield strength against corrosion cracking, is shown

  10. Corrosion of steel structures in sea-bed sediment

    Indian Academy of Sciences (India)

    Xiutong Wang; Jizhou Duan; Yan Li; Jie Zhang; Shide Ma; Baorong Hou

    2005-04-01

    Seabed sediment (SBS) is a special soil that is covered by seawater. With the developments in marine oil exploitation and engineering, more and more steel structures have been buried in SBS. SBS corrosion has now become a serious problem in marine environment and an important issue in corrosion science. In this paper, approach in the field of SBS corrosion is reviewed. Electrochemical and microbial corrosion factors, corrosion mechanism, measurement of metal corrosion rate, corrosion evaluation and prediction of corrosion are also discussed here.

  11. Kinetics and structural studies of the atmospheric corrosion of carbon steels in Panama

    International Nuclear Information System (INIS)

    The corrosion of a carbon steel was studied in different atmospheres at sites in the Republic of Panama. The weight loss (corrosion penetration) suffered by the carbon steel is related to time by a bilogarithmic law. Moessbauer spectroscopy indicated the rust was composed of non-stoichiometric magnetite (Fe3-xO4), maghemite (?-Fe2O3), goethite (?-FeOOH) of intermediate particle size, lepidocrocite (?-FeOOH) and superparamagnetic particles. Magnetite formation is related to the alternating dry-wet cycles. Goethite is related to corrosion penetration by a saturation type of behavior, following a Langmuir type of relationship. Goethite in rust protects steel against further atmospheric corrosion

  12. Kinetics and structural studies of the atmospheric corrosion of carbon steels in Panama

    Science.gov (United States)

    Jaén, Juan A.; de Villalaz, Mariela Sánchez; de Araque, Lilibeth; de Bósquez, Agnes

    1997-09-01

    The corrosion of a carbon steel was studied in different atmospheres at sites in the Republic of Panama. The weight loss (corrosion penetration) suffered by the carbon steel is related to time by a bilogarithmic law. Mössbauer spectroscopy indicated the rust was composed of non-stoichiometric magnetite (Fe3-xO4), maghemite (?-Fe2O3), goethite (?-FeOOH) of intermediate particle size, lepidocrocite (?-FeOOH) and superparamagnetic particles. Magnetite formation is related to the alternating dry--wet cycles. Goethite is related to corrosion penetration by a saturation type of behavior, following a Langmuir type of relationship. Goethite in rust protects steel against further atmospheric corrosion.

  13. Corrosion damage of welded steel 17247

    International Nuclear Information System (INIS)

    Corrosion effects arising from welded joints of austenitic steel CSN (Czechoslovak Standard) 17247 were studied. Test specimens were taken from two heats; the one had standard chemical composition, whereas the other had elevated titanium content, viz. nearly twelvefold the carbon content. The samples were welded without preheating by manual arc welding, and successively exposed to two corrosion media: 10% ferric chloride, and a solution of copper sulfate and sulfuric acid in distilled water containing copper filings. The corrosion effect depended substantially on the previous surface finishing. Conventionally finished samples exhibited the highest corrosion resistance, electrolytically polished samples followed, whereas samples treated by cast iron grit blasting displayed the lowest resistance. Neither the base material nor the weld material exhibited tendency to intergranular corrosion in sulfuric acid. In ferric chloride solution, the weld material was only slightly affected with respect to the base material. (Z.M.). 11 refs

  14. A Comparative Study on causes of corrosion of steel reinforcement in RC structures at Bangalore, India and Kigali, Rwanda

    Directory of Open Access Journals (Sweden)

    Abaho G

    2015-06-01

    Full Text Available Premature failure of reinforced concrete structures occurs primarily due to early corrosion of steel reinforcement. This paper intends to uplift the awareness of people about the role of structure maintenance to prevent or control corrosion in steel reinforced concrete structures. Some data collected using a designed questionnaire were distributed in Bangalore, India and Kigali, Rwanda, about corrosion of steel reinforcement which actually motivated this research. The research finds that without corrosion in steel reinforced concrete structures is just a matter of time. However corrosion map for Kigali is not available. Hence the survey has been conducted in Rwanda. Based on survey corrosion map will be prepared so that vulnerable areas for corrosion can be identified. This map will enable for protective design of structures against corrosion. The new steel RC structures corrosion monitoring systems should be incorporated for future less costly, timely maintenance for their reliable service life.

  15. Influence of temperature on corrosion rate and porosity of corrosion products of carbon steel in anoxic bentonite environment

    Energy Technology Data Exchange (ETDEWEB)

    Stoulil, J., E-mail: jan.stoulil@vscht.cz [Department of Metals and Corrosion Engineering, Institute of Chemical Technology, Prague (Czech Republic); Ka?ok, J.; Kou?il, M. [Department of Metals and Corrosion Engineering, Institute of Chemical Technology, Prague (Czech Republic); Parschová, H. [Department of Power Engineering, Institute of Chemical Technology, Prague (Czech Republic); Novák, P. [Department of Metals and Corrosion Engineering, Institute of Chemical Technology, Prague (Czech Republic)

    2013-11-15

    Highlights: •The corrosion rate is not significantly dependent on temperature. •Corrosion products at higher temperatures have different color. •Corrosion products at higher temperatures are more compact. •The change in corrosion products nature is reversible. -- Abstract: The study focuses on the porosity of layers of corrosion products and its impact on corrosion rate of carbon steel in moist bentonite. Measurements were performed in an aggressive Czech type of bentonite – Rokle B75 at temperatures of 90 and 40 °C. Aggressiveness of B75 bentonite consists in low content of chlorides. Presence of chlorides in pore solution allows formation of more protective magnetite. The evaluation was made by electrochemical techniques (red/ox potential, open circuit potential, linear polarization resistance, impedance spectroscopy) and resistometric sensor measurements. The result imply that the higher the temperature the more compact is the layer of corrosion products that slightly decelerates corrosion rate compared to the state at 40 °C. The state of corrosion products at both temperatures is reversible.

  16. Valuation of surfactant Phosphonates synthesized in the protection of metal surfaces against corrosion of mild steel in 0.5M H2SO4 media

    Directory of Open Access Journals (Sweden)

    R. Ghibate

    2015-12-01

    Full Text Available In this article, we are interesting to investigate the corrosion inhibition of mild steel in sulfuric acid by two surfactants phospohonates already synthesized namely sodium methyldodecylphosphonate (Pho1 and sodium methyl (11-methacryloyloxyundecyl phosphonate (Pho2. The inhibition performances of Pho1 and Pho2 on mild steel corrosion in 0,5M H2SO4 solution were studied using the electrochemical impedance spectroscopy (EIS, weight loss, and Tafel polarization technics. The experimental results suggest that those surfactants are effective corrosion inhibitors and the inhibition efficiency increases with the increase surfactants concentrations. Polarization measurements proved that the inhibitors behave as mixed-type. EIS diagram appears a large capacitive loop at high frequencies (HF followed by a small inductive loop at low frequencies (LF for Pho2, and the addition of this surfactant inhibitor increases the impedance of electrode. The adsorption of each surfactant on steel surface obeys Langmuir adsorption isotherm. The thermodynamic and kinetic parameters were calculated and discussed. Values of inhibition efficiency calculated from weight loss, Tafel polarization curves, and EIS are in good agreement.

  17. Polyaspartic acid as a green corrosion inhibitor for carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Cui, R. [Department of Chemistry, Hebei Normal University, Shijiazhuang 050016 (China); Department of Chemistry and Materials Engineering, Changshu Institute of Technology, Changshu 215500 (China); Gu, N.; Li, C. [Department of Chemistry, Hebei Normal University, Shijiazhuang 050016 (China)

    2011-04-15

    The inhibitor effect of the environmentally friendly corrosion inhibitor polyaspartic acid (PASP) on the corrosion of carbon steel in 0.5 M H{sub 2}SO{sub 4} was investigated by weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). Polarization curve results clearly reveal the fact that PASP is a good anode-type inhibitor. EIS results confirm its corrosion inhibition ability. The inhibition efficiency increases with increasing PASP concentration, and the maximum inhibition efficiency was 80.33% at 10 C. SEM reveals that a protective film forms on the surface of the inhibited sample. The adsorption of this inhibitor is found to follow the Freundlich adsorption isotherm. A mechanism is proposed to explain the inhibitory action of the corrosion inhibitor. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Space Shuttle Corrosion Protection Performance

    Science.gov (United States)

    Curtis, Cris E.

    2007-01-01

    The reusable Manned Space Shuttle has been flying into Space and returning to earth for more than 25 years. The launch pad environment can be corrosive to metallic substrates and the Space Shuttles are exposed to this environment when preparing for launch. The Orbiter has been in service well past its design life of 10 years or 100 missions. As part of the aging vehicle assessment one question under evaluation is how the thermal protection system and aging protective coatings are performing to insure structural integrity. The assessment of this cost resources and time. The information is invaluable when minimizing risk to the safety of Astronauts and Vehicle. This paper will outline a strategic sampling plan and some operational improvements made by the Orbiter Structures team and Corrosion Control Review Board.

  19. Materials corrosion and protection from first principles

    Science.gov (United States)

    Johnson, Donald F.

    Materials erode under environmental stresses such as high temperature, high pressure, and mechanical shock/stress, but erosion is often exacerbated by chemical corrosion. In this dissertation, periodic density functional theory (DFT) is employed to simulate interfacial adhesion, absorption kinetics, bulk diffusion, and other material phenomena (e.g., hydrogen-enhanced decohesion and shock-induced phase changes) with the intention of understanding corrosion and subsequent failure processes and guiding the design of new protective coatings. This work examines corrosion and/or protection of materials ( i.e., Fe, Ni, W) with important applications: structural steel, gun tubes, high-pressure oil recovery vessels, jet engine turbine blades, and fusion reactor walls. We use DFT to model the pressure-induced, bcc-to-hcp phase transformation in Fe, in which a new low energy pathway is predicted exhibiting nonadiabatic behavior coupling magnetic and structural changes. Protection of steel is addressed in two aspects: interfacial adhesion of protective coatings and assessment of corrosion resistance provided by a surface alloy. First, the current chrome-coated steel system is examined where extremely strong adhesion is predicted at the Cr/Fe interface originating in strong spin correlations. A ceramic coating, SiC, is considered as a possible replacement for Cr. Strong adhesion is predicted, especially for C-Fe interfacial bonds. To assess corrosion resistance, we model ingress of two common corrosive elements, H and C, into two Fe alloys, FeAl and Fe3Si. Adsorption and absorption thermodynamics and kinetics, as well as bulk dissolution and diffusion are calculated in order to determine whether these two alloys can inhibit uptake of H and C. Relative to pure Fe, dissolved H and C are less stable in the alloys, as the dissolution enthalpy is predicted to be more endothermic. Overall, the energy barriers and rate constants for adsorbed H/C diffusing into Fe3Si subsurface layers suggests that alloying Fe with Si can be an effective means to limit uptake of these elements into steel. Spallation of protective layers on jet engine turbine blades is a problem that arises during thermal cycling. An alternative thermal barrier coating system involving MoSi2 is considered and calculations predict strong adhesion at the MoSi2/Ni interface. The interfacial bonding structure reveals a mixture of metallic and covalent cross-interface bonds. The adhesion energy is similar across all three MoSi2 facets studied. Upon exposure to oxygen, this MoSi2 alloy will form a strongly adhered oxide scale, which in turn may strongly adhere the heat shield material (yttria-stabilized zirconia), thereby potentially extending the lifetime of the barrier coating. Lastly, the interaction of hydrogen isotopes (fusion fuel) with tungsten (a proposed fusion reactor wall material) is examined. Exothermic dissociative adsorption is predicted, along with endothermic absorption and dissolution. Surface-to-subsurface diffusion energy barriers for H incorporation into bulk W are large and the corresponding outward diffusion barriers are very small. In bulk W, deep energetic traps (trapping multiple H atoms) are predicted at vacancy defects. Thus, under high neutron fluxes that will produce vacancies in W, H are predicted to collect at these vacancies. In turn, locally high concentrations of H at such vacancies will enhance decohesion of bulk W, consistent with observed blistering under deuterium implantation. Limiting vacancy formation may be key to the survival of W as a fusion reactor wall material.

  20. Corrosion of martensitic and ferritic steels in nuclear power plants

    International Nuclear Information System (INIS)

    In nuclear reactor operation martensite or ferritic corrosion resistant steels come in contact with solutions used for desactivation prior to dismantling, repairs, etc. The most frequent type of corrosion is stress corrosion cracking. For achieving good corrosion resistance material heating should be avoided in mechanical treatment. Low-resistance corrosion centres may also result from the penetration of common steel particles, eg., in grinding. The corrosion resistance test can be effected by placing filter paper soaked with the said solution on the steel surface. Corrosion centres will be evident by their blue colouring after 10 minutes. (J.B.)

  1. Microbial Corrosion and Cracking in Steel

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    1998-01-01

    recommendations in regards to electrochemical monitoring of MIC. The work presented here and further studies are also planned to lead to a Ph.D. thesis on "MIC monitoring based on mechanisms of corrosion".The results of laboratory experiments conducted in the period 1995 to 1997 are summarised. Conclusions will...... be based on results from the entire 3 year period, but only selected experimental data primarily from the latest experiments will be presented in detail here.Microbial corrosion of carbon steel under influence of sulphate-reducing bacteria (SRB) is characterised by the formation of both biofilm and...... corrosion products (ferrous sulphides) on the metal surface. Experiments have been conducted on carbon steel exposed in near neutral (pH 6 to 8.5) saline hydrogen sulphide environment (0 to 100 mg/l total dissolved sulphide) for a period of 14 days. Furthermore coupons have been exposed in a bioreactor for...

  2. 49 CFR 193.2625 - Corrosion protection.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Corrosion protection. 193.2625 Section 193.2625...: FEDERAL SAFETY STANDARDS Maintenance § 193.2625 Corrosion protection. (a) Each operator shall determine which metallic components could, unless corrosion is controlled, have their integrity or...

  3. Internal corrosion of carbon steel piping in hot aquifers service

    OpenAIRE

    Simi?i? Miloš V.; Govedarica Dragan D.

    2011-01-01

    Internal corrosion of carbon steel pipelines is a major problem encountered in water service. In terms of prediction of the remaining lifetime for water pipelines based on the corrosion allowance, the three main approaches are corrosion modelling, corrosion inhibitor availability, and corrosion monitoring. In this study we used two theoretical corrosion models, CASSANDRA and NORSOK M-506 of quite different origin in order to predict uniform corrosivity of hot aquifers in eight different...

  4. Corrosion protection and control using nanomaterials

    CERN Document Server

    Cook, R

    2012-01-01

    This book covers the use of nanomaterials to prevent corrosion. The first section deals with the fundamentals of corrosion prevention using nanomaterials. Part two includes a series of case studies and applications of nanomaterials for corrosion control.$bCorrosion is an expensive and potentially dangerous problem in many industries. The potential application of different nanostructured materials in corrosion protection, prevention and control is a subject of increasing interest. Corrosion protection and control using nanomaterials explores the potential use of nanotechnology in corrosion control. The book is divided into two parts. Part one looks at the fundamentals of corrosion behaviour and the manufacture of nanocrystalline materials. Chapters discuss the impact of nanotechnology in reducing corrosion cost, and investigate the influence of various factors including thermodynamics, kinetics and grain size on the corrosion behaviour of nanocrystalline materials. There are also chapters on electrodeposition ...

  5. Corrosion Behavior of Copper-Steel Particulate Composite

    OpenAIRE

    J. T. AL-Haidary; Emad Al-Hassani; Sheelan R. Areef

    2011-01-01

    This work was conducted to study the corrosion behavior of the steel particle reinforced copper matrix composites, under different conditions; namely heat treatment, concentration of corrosion media, and different weight percent of steel particles.The density, corrosion rate, micro-structure, and Vickers micro-hardness, were investigated. The results showed that composites with limited steel particle contents can be used. The microstructure of the composites showed severe corrosion of the ste...

  6. Corrosion and Stress Corrosion Behaviors of Low and Medium Carbon Steels in Agro-Fluid Media

    OpenAIRE

    Ayo Samuel AFOLABI

    2007-01-01

    Investigations were carried out to study critically the corrosion behaviour and Stress Corrosion Cracking (SCC) of low and medium carbon steels in cassava and cocoa extracts by weight loss measurement and constant extension to fracture method respectively. The results obtained showed that medium carbon steel is more susceptible to corrosion than low carbon steel in both media. SCC is also more in medium carbon steel than low carbon steel in the two media under study. These deductions are due ...

  7. Investigation of Carbon steel corrosion in water base drilling mud

    OpenAIRE

    Fadhil Sarhan Kadhim

    2011-01-01

    Carbon steel, the most widely used engineering material, accounts for approximately 85%, of the annual steel production worldwide. Despite its relatively limited corrosion resistance, carbon steel is used in large tonnages in marine applications, nuclear power and fossil fuel power plants, transportation, chemical processing, petroleum production and refining, pipelines, mining, construction and metal-processing equipment. This paper Investigate Carbon steel corrosion in water. The corrosion ...

  8. Interaction between Cathodic Protection and Microbially Influenced Corrosion.

    OpenAIRE

    Bujang Masli, Azlan Bin

    2011-01-01

    The present work studied the interaction between cathodic protection and microbiallyinfluenced corrosion (MIC) on the surface of mild steel. Potential trending wasobserved when the currents were held constant, and current trending was observedwhen potentials were held constant. Scanning electron microscopy and energydispersive x-ray spectroscopy were used to study surface deposits on the samples andfurther understand the result of the interaction. Sul...

  9. Reinforcement steel corrosion in passive state and by carbonation: Consideration of galvanic currents and interface steel - concrete defaults

    International Nuclear Information System (INIS)

    This thesis aims to study the durability of nuclear waste deep storage structures. The work carried out is essentially an experimental study, and focuses on the corrosion of steel in the passive state with aerated or non-aerated conditions on the one hand, and the corrosion of steel in carbonated concrete during the propagation phase on the other hand. Indeed, the pore solution of concrete in contact with the metal is alkaline (pH between 12 and 13). Under these conditions, steel reinforced concrete remains passive by forming a stable and protective oxide layer (corrosion of steel in the passive state). This passive layer limits the steel corrosion rate at very low values (negligible on a short life time) but not null. For the nuclear waste storage structures due to a very long life time (up to several hundred years), this low corrosion rate can become a risk. Therefore, it is necessary to study the evolution of the oxide layer growth over time. The objectives of the thesis are to study the influence of the steel-concrete interface quality on reinforcement corrosion in passive and active state, and the possible occurrence of galvanic corrosion currents between different reinforcement steel areas. (author)

  10. Protect nuclear plant fasteners from boric acid corrosion

    International Nuclear Information System (INIS)

    Boric acid corrosion of pump and valve fasteners in pressurized water reactor (PWR) power plants can be prevented by implementing appropriate fastener steel replacement and extended inspections to detect and correct the cause of leakage. In this paper a three-phase corrosion protection program based on system operability, outage-related accessibility, and cost of fastener replacement versus maintenance frequency increase is presented. A selection criteria for fastener material is also presented. Degradation or failure of pressure retaining fasteners at pumps and valves has been reported in several areas exposed to leakage of closures in long-term service. The resulting boric acid corrosion experienced in PWR systems is defined as an accelerated process produced when water evaporates from leaking coolant. The primary detrimental effect of boric acid leakage is wastage (or general dissolution corrosion) of low-alloy carbon steel fasteners

  11. Steel corrosion in hot brine

    International Nuclear Information System (INIS)

    In the framework of the research project, the electrochemical examinations of the corrosion rate and the kinetics of the formation of oxides on iron in dependence on temperatures of up to 3000C, on the corrosion potential and the solvent composition were continued under pressures of less than 100 bar generated by a medium-pressure apparatus. A high-pressure apparatus for electrochemical measurements of the equilibrium potential of the iron electrode and the corresponding equilibrium partial pressure of the hydrogen at system pressures of up to 4 kbar and at high temperatures, and a corresponding medium-pressure apparatus for the determination of the solubility of iron oxides were completed and first measurements with this apparatus were taken. (orig./RB)

  12. The assessment of corrosion type and corrosion rate of carbon steel in compacted bentonite

    International Nuclear Information System (INIS)

    Carbon steel is one of the candidate materials for overpacks for high-level radioactive waste disposal in Japan. The estimation of corrosion allowance of carbon steel overpack needs to clarify the type of corrosion and the corrosion rate under repository conditions. The type of the corrosion occurring on overpacks depends on whether carbon steel is passivated or not. If carbon steel is passivated under repository conditions, localized corrosion such as pitting, crevice corrosion and stress corrosion cracking may occur under some conditions. On the other hand, if carbon steel is not passivated under repository conditions, general corrosion will occur. Passivation behavior and corrosion rate of carbon steel were investigated by electrochemical measurements under simulated repository conditions. The results of the measurements showed that carbon steel was hard to passivate in highly compacted bentonite. The immersion tests were carried out in compacted bentonite and average corrosion rates were measured from weight loss and the AC impedance of carbon steel specimens. The database of average corrosion rate were made from the data obtained by the weight loss technique. Based on the database of average corrosion rate in compacted bentonite, the relationship between average corrosion rates and test conditions were investigated. The average corrosion depth for 1000years was also estimated to be less than 5 mm. In order to simulate the accumulation of corrosion products after long term, the external current were supplied to carbon steel specimens. After the formation of corrosion products, corrosion rates were measured using AC impedance technique. The results of the measurements showed that the corrosion rate of carbon steel did not increase in the presence of corrosion products formed by external current supply. (author)

  13. Corrosion of carbon steel in the stagnant cooling water

    International Nuclear Information System (INIS)

    In the cooling water system treated with zinc-polyphosphate inhibitor, the relationship between inhibitor performance and corroded conditions of heat exchangers was studied. When cooling water system was kept in wet lay-up state, inhibitor concentration in the water jucket of heat exchangers decreased 15 ? 30 percent per week, and turbidity increased 30 ? 150 percent per week. These results show that corrosion rate of shell-plate in stagnant cooling water is more rapid than in flowing cooling water. Applied trouble discrimination method based on SiO2 ratio to the chemical composition of corrosion products, corrosion trouble was observed in shell-plates of heat exchangers. When cooling water system is kept in wet lay-up state, cooling water in the water jucket of heat exchangers is isolated for mouter system. In this perfectly closed system, zinc-polyphosphate inhibitor was not effective for protection of corrosion of carbon steel, and metal (carbon steel) dissolution occurred. However, in the perfectly closed system, since the dissolved oxygen content of the system was reduced with lapse of time, reduction process at cathodic region was stopped, so corrosion of metals seemed to be inhibited. (author)

  14. Corrosion of two kinds of cast steels containing chromium in hot concentrated alkaline

    Directory of Open Access Journals (Sweden)

    LI Wei

    2007-02-01

    Full Text Available A typical hot concentrated alkaline corrosion environment exists in alumina metallurgical industry, so that steel materials with outstanding alkaline corrosion resistance are strongly demanded for its processing equipment. In this paper, the corrosion resistance of two kinds of martensitic cast steels containing chromium in static 303g/L NaOH alkaline solution at 85? was studied through polarization and potential-time curves, corrosion weight loss and corrosion morphology analysis. Experimental results showed that protection effect by passive film of cast steel containing Cr was temporary. The low carbon steel without Cr content also exhibited chemical passivity in the same solution. The corrosion mode of the tested Cr-containing cast steel was composed of active dissolving corrosion and caustic embrittlement cracking. Dissolving corrosion was the primary mechanism for the induced weight loss, while severe caustic embrittlement cracking was secondary. With the increase of chromium content in the cast steel, the tendency of the caustic embrittlement cracking decreased, while the active dissolving corrosion increased.

  15. Corrosion behaviour of carbon steel in contact with bentonite under anaerobic condition

    International Nuclear Information System (INIS)

    Full text of publication follows: The geological disposal system of high-level radioactive waste (HLW) consists of vitrified waste, overpack, buffer material and surrounding rock. In this system, overpack is required to prevent the contact of groundwater from vitrified waste for 1000 years. The main factor limiting this function is corrosion due to the contact with groundwater infiltrated to buffer material which is the mixture of bentonite and sand. Carbon steel is selected as one of the candidate materials for overpacks in Japan as a corrosion allowance metal. The deep underground environment for geological disposal of HLW is expected to be relatively oxidizing condition at the initial stage of repository, but it will be returned to reducing as the consumption of oxygen by the corrosion of overpack and the redox reactions with the minerals in buffer material. It is necessary to understand the corrosion behaviour of carbon steel under such anaerobic condition for the lifetime prediction of carbon steel overpack. In this study, immersion tests of carbon steel in buffer material were performed in nitrogen atmosphere in which oxygen gas concentration was controlled less than 1 ppm. The corrosion rates of carbon steel were measured by weight loss of the specimens and the corrosion products were analysed by SEM, XRD and EPMA. For investigating the influence of welding of overpack, welded samples by electron-beam welding (EBW) were used in some of the tests. Synthetic sea water (SSW) and aqueous solutions containing bicarbonate ion and chloride ion were chosen as simulated groundwater. The results indicated that the corrosion form of carbon steel under anaerobic condition was uniform corrosion and no localised corrosion such as pitting, crevice corrosion was found within our experimental conditions. Ferrous carbonate such as FeCO3 or Fe2(OH)2CO3 was identified as crystalline corrosion products by XRD. Although the corrosion rate was affected by test solution and buffer material design, the corrosion products film formed on the surface at 353 K were tight and very small corrosion rates less than 1?m/y was obtained in any cases. While, the corrosion product at 323 K was not protective and larger corrosion rate of 2?m/y was estimated. There was no influence of steel type and welding on the corrosion rate of carbon steel up to 3 years of immersion period. The average corrosion depth of carbon steel overpack was calculated to be ? 2 mm by extrapolating the obtained corrosion rate of ? 2?m/y to 1000 years, and this estimation was well agreed with natural analogue data. (authors)

  16. The behaviour of praseodymium 4-hydroxycinnamate as an inhibitor for carbon dioxide corrosion and oxygen corrosion of steel in NaCl solutions

    International Nuclear Information System (INIS)

    Highlights: •Praseodymium 4-hydroxycinnamate (Pr(4OHCin)3) highly effective corrosion inhibitor. •Mechanism of inhibition different in CO2-saturated solutions compared to aerated system. •In natural aerated solutions a continuous protective film forms on the steel surface. •In CO2-saturated solutions inhibiting deposits form at active corrosion sites. -- Abstract: Praseodymium 4-hydroxycinnamate (Pr(4OHCin)3) was investigated as a novel corrosion inhibitor for steel in NaCl solutions, and found to be effective at inhibiting corrosion in both CO2-containing and naturally-aerated systems. Surface analysis results suggest that the corrosion inhibition ability of Pr(4OHCin)3 in the naturally-aerated corrosion system could be attributed to the formation of a continuous protective film. For the CO2-containing system, the corrosion inhibition efficiency of Pr(4OHCin)3 was predominantly because of formation of protective inhibiting deposits at the active electrochemical corrosion sites, in addition to a thinner surface film deposit

  17. On the inhibition of hydrogen sulfide corrosion of steel with Schiff Bases

    International Nuclear Information System (INIS)

    The number of the Schiff bases(above 20 compounds) is synthesized. Their impact on the kinetics of electrochemical reactions and steel corrosion behaviour in the two-phase systems electrolyte - hydrocarbon containing H2S, is studied. It is shown, that azomethines, synthesized by the Schiff reaction from aldehydes and aliphatic amines, may serve as water-soluble inhibitors in these systems. The efficiency of steel corrosion protection against hydrogen sulfide corrosion through azomethines depends on their chemical structure and pH media. The effective water-soluble inhibitor of the hydrogen sulfide corrosion - IFKhAN-62 - is developed

  18. Development of ion-plated aluminide diffusion coatings for thermal cyclic oxidation and hot corrosion protection of a nickel-based superalloy and a stainless steel

    Science.gov (United States)

    Elsawy, Abdel Raouf

    This project was carried out at the University of Toronto and Cametoid Ltd of Whitby, Ontario. Ohno continuous casting; a novel net shape casting technique, was used to generate, Al-Y, Al-Ce, Al-La, and Al-Si-Y, in form of 1.6 to 1.7 mm diameter alloy wires. These alloy wires exhibited suitable properties for use as feed materials to an Ion Vapor Deposition facility. The deposition parameters were optimized to provide coatings with a compact and cohesive columnar structure with reduced porosity and diffusion barriers that were essential to ensure the success of the diffusion process in the subsequent stage. Solid-state diffusion heat treatment processes were developed in order to form the stable aluminide phases, AlNi and FeAl, on IN738 and S310 substrates, respectively. Experiments simulating the coating service conditions and environments encountered during the prospective aerospace and fuel cell applications were conducted to evaluate the performance of each aluminide coating developed during this study. Thermal cyclic oxidation and molten sulfate corrosion studies were performed on coated IN738 pins at 1050°C and 900°C, respectively, simulating the service environment of turbine engine blades and other hot section components. Molten carbonate corrosion behavior was investigated for coated S310 coupons that were immersed in, or covered with a thin film of molten carbonate, at 650°C, in air plus 30%CO2, to simulate the operating conditions of the cathode-side separator plates of molten carbonate fuel cells. The behavior of the reactive elements, yttrium, cerium, lanthanum, and silicon in enhancing the adhesion of the protective aluminum oxide scale was determined by weight variation experiments, structural examination and compositional analysis. The influence of the base material elements, nickel, chromium, and iron, on the formation of protective oxides was investigated. All coatings were found to provide significant improvement for thermal cyclic oxidation and hot corrosion protection. For protection of IN738, Al-La coatings provided the greatest protection during oxidative thermal cycling, whereas Al-Ce coatings were found to be the most effective for protection against corrosive molten sulfate environments in aerospace applications. For protection of S310 against the corrosive environments of molten carbonate fuel cells, the effectiveness of the aluminide coatings were in the sequence, from the most to the least effective, Al-La, Al-Ce, Al-Y, and Al-Si-Y Mechanisms for Lanthanum and cerium protective behavior in high temperature aluminide diffusion coatings were suggested from the results of this study combined with literature information.

  19. Mechanism and degree of chemical elements effect on atmosphere corrosion resistance of steels

    International Nuclear Information System (INIS)

    It follows from the proposed regression equations that falourable effect of chemical elements on steel resistance to atmospheric corrosion is determined by their ability to increase interatom bond stability in iron crystal lattice and form corrosion products with high protection properties. Element positive influence on steel corrosion resistance decreases in the following order: S, P, Si, Mn, Cu, Cr, Ni, C in semiurban tropical atmosphere and S, Mn, Sr, Cu, Ni, Cr in coastal atmosphere. In the latter case C increases corrosion in a greater degree as compared to P. Small ammounts of Mo decrease steel resistance in semiurban atmosphere and almost do not influence it in the coastal one. Possible mechanisms of individual element influence on steel corrosion resistance are considered

  20. Production, properties and application of steels resistant to atmospheric corrosion

    International Nuclear Information System (INIS)

    Steels, resistant to atmospheric corrosion, applied in the USSR and abroad, are reviewed. The influence of alloying elements (Cu, P, Cr, Si, Ni, Mo, Mn, As etc) upon resistance against atmospheric corrosion and mechanical properties of rolled steel is discussed. Technological properties, fields of the above steels application as well as the data on the range of product, are presented

  1. Marine atmospheric corrosion of carbon steels

    Directory of Open Access Journals (Sweden)

    Morcillo, Manuel

    2015-06-01

    Full Text Available Basic research on marine atmospheric corrosion of carbon steels is a relatively young scientific field and there continue to be great gaps in this area of knowledge. The presence of akaganeite in the corrosion products that form on steel when it is exposed to marine atmospheres leads to a notable increase in the corrosion rate. This work addresses the following issues: (a environmental conditions necessary for akaganeite formation; (b characterisation of akaganeite in the corrosion products formed; (c corrosion mechanisms of carbon steel in marine atmospheres; (d exfoliation of rust layers formed in highly aggressive marine atmospheres; (e long-term corrosion rate prediction; and (f behaviour of weathering steels. Field research has been carried out at Cabo Vilano wind farm (Camariñas, Galicia in a wide range of atmospheric salinities and laboratory work involving the use of conventional atmospheric corrosion techniques and near-surface and bulk sensitive analytical techniques: scanning electron microscopy (SEM/energy dispersive spectrometry (EDS, X-ray diffraction (XRD, Mössbauer spectroscopy and SEM/?Raman spectroscopy.La investigación fundamental en corrosión atmosférica marina de aceros al carbono es un campo científico relativamente joven que presenta grandes lagunas de conocimiento. La formación de akaganeíta en los productos de corrosión que se forman sobre el acero cuando se expone a atmósferas marinas conduce a un incremento notable de la velocidad de corrosión. En el trabajo se abordan las siguientes cuestiones: (a condiciones ambientales necesarias para la formación de akaganeíta, (b caracterización de la akaganeíta en los productos de corrosión formados, (c mecanismos de corrosión del acero al carbono en atmósferas marinas, (d exfoliación de las capas de herrumbre formadas en atmósferas marinas muy agresivas, (e predicción de la velocidad de corrosión a largo plazo, y (f comportamiento de aceros patinables. La investigación se ha llevado a cabo en campo, en el Parque Eólico de Cabo Vilano (Camariñas, Galicia en un amplio rango de salinidades atmosféricas, y a nivel de laboratorio acudiendo a técnicas convencionales de corrosión atmosférica y diversas técnicas analíticas de caracterización de superficies: microscopía electrónica de barrido (MEB/ espectrometría de dispersión de energía (EDE, difracción de rayos-X (DRX, espectroscopía Mössbauer y MEB/espectroscopía ?Raman

  2. Microbial corrosion and cracking in steel. Assessment of soil corrosivity using an electrochemical soil corrosion probe

    Energy Technology Data Exchange (ETDEWEB)

    Vendelbo Nielsen, L.

    1998-08-01

    An electrochemical soil corrosion probe has been designed, manufactured, and tested at five different locations in the field. The probe includes facilities for hydrogen permeation measurements, local soil resistivity measurements by the Wenner fourpoint method, and open circuit potential measurements on carbon steel- and high-alloyed (SMO-254) stainless steel electrodes. The carbon steel electrodes were arranged as two sets of three-electrode arrangements. Using these arrangements, electrochemical impedance spectroscopy (EIS), galvanostatic pulse (GP) measurements, and DC polarisation scans were applied for characterisation of the corrosion conditions present in the soil. (au) EFP-95. 21 refs.

  3. Atmospheric corrosion of mild steel in Oman

    International Nuclear Information System (INIS)

    A systematic study has been made of the initial corrosion products which form on mild steel capons exposed near the coastal region of Oman and at some industrial areas. The phases and compositions of the products formed at different periods of exposure were examined by using Moessbauer spectroscopy (295 and 78 K) and X-ray diffraction (XRD) techniques. The results show that lepidocorcite and maghemite are early corrosion products and goethite starts to form after 2 months of metal exposure to the atmosphere. Akaganeite is an early corrosion product but it forms in marine environments only, which reflects the role of chlorine effect in the atmosphere. The 12 months coupons showed the presence of goethite, lepidocorcite and maghemite, but no akaganeite being seen in the products of one of the studied areas.

  4. Phenomenological investigation of the influence of Cathodic protection on corrosion fatigue crack propagation behaviour, in a BS 4360 50D type structural steel and associated weldment microstructures, in a marine environment.

    OpenAIRE

    Thompson, J. W. C.

    1984-01-01

    The influence of Cathodic Protection potential upon corrosion fatigue crack propagation rates in a medium7strength ferritic-pearlitic structural steel (ES 4360 grade 50D) and associated weldment microstructures in simulated sea-water was studied and the results were presented in bi-modal da/dN vs AK curves. Above transition propagation rate data was satisfactorily described by the Paris relationship da/dN = C. AKm and a relationship of the formin = Aln C+D between Paris e...

  5. Corrosion behavior of low alloy steels containing Cr, Co and W in synthetic potable water

    International Nuclear Information System (INIS)

    The corrosion behavior of new alloy steels was investigated using potentiodynamic (PD) tests, electrochemical impedance spectroscopy (EIS) and galvanostatic test in synthetic potable water. PD test results showed that all specimens exhibited active corrosion behavior, and corrosion rate tended to decrease as a result of adding alloying elements. The EIS measurements were taken to determine the polarization resistance (RP) of the rust layer. The RP values of the new alloy steel were much larger than that of carbon steel. Furthermore, more alloying elements led to a remarkable increase in the RP values. The chemical state of alloying elements (Cr, Co and W) in the rust layer of new alloy steels was analyzed by electron probe microanalysis (EPMA) and X-ray photoelectron spectroscopy (XPS). EPMA and XPS results showed that alloying elements existed in protective compounds in the rust layer. Corrosion of the new alloy steels was suppressed by insoluble compound formed near the surface

  6. Galvanic corrosion between carbon steel 1018 and Alloy 600 in crevice with boric acid solution

    International Nuclear Information System (INIS)

    This work dealt with the evaluation of galvanic corrosion rate in a corrosion cell having annular gap of 0.5 mm between carbon steel 1018 and alloy 600 as a function of temperature and boron concentration. Temperature and boron concentration were ranged from 110 to 300 .deg. C and 2000?10000 ppm, respectively. After the operating temperature of the corrosion cell where the electrolyte was injected was attained at setting temperature, galvanic coupling was made and at the same time galvanic current was measured. The galvanic corrosion rate decreased with time, which was described by corrosion product such as protective film as well as boric acid deposit formed on the carbon steel with time. From the galvanic current obtained as a function of temperature and boron concentration, it was found that the galvanic corrosion rate decreased with temperature while the corrosion rate increased with boron concentration. The experimental results obtained from galvanic corrosion measurement were explained by adhesive property of corrosion product such as protective film, boric acid deposit formed on the carbon steel wall and dehydration of boric acid to be slightly soluble boric acid phase. Moreover the galvanic corrosion rate calculated using initial galvanic coupling current instead of steady state coupling current was remarked, which could give us relatively closer galvanic corrosion rate to real pressurized water reactor

  7. Corrosion aspects of steel radioactive waste containers in cementitious materials

    International Nuclear Information System (INIS)

    Nick Smart from Serco, UK, gave an overview of the effects of cementitious materials on the corrosion of steel during storage and disposal of various low- and intermediate-level radioactive wastes. Steel containers are often used as an overpack for the containment of radioactive wastes and are routinely stored in an open atmosphere. Since this is an aerobic and typically humid environment, the steel containers can start to corrode whilst in storage. Steel containers often come into contact with cementitious materials (e.g. grout encapsulants, backfill). An extensive account of different steel container designs and of steel corrosion mechanisms was provided. Steel corrosion rates under conditions buffered by cementitious materials have been evaluated experimentally. The main conclusion was that the cementitious environment generally facilitates the passivation of steel materials. Several general and localised corrosion mechanisms need to be considered when evaluating the performance of steel containers in cementitious environments, and environmental thresholds can be defined and used with this aim. In addition, the consequences of the generation of gaseous hydrogen by the corrosion of carbon steel under anoxic conditions must be taken into account. Discussion of the paper included: Is crevice corrosion really significant in cementitious systems? Crevice corrosion is unlikely in the cementitious backfill considered because it will tend to neutralise any acidic conditions in the crevice. What is the role of microbially-induced corrosion (MIC) in cementitious systems? Microbes are likely to be present in a disposal facility but their effect on corrosion is uncertain

  8. Corrosion and Corrosion Protection of AZ31 Mg Alloy

    OpenAIRE

    Moon, Sungmo

    2015-01-01

    Corrosion behavior of AZ31 Mg alloy was studied in chloride and alkaline solutions, and two different surface treatments of chemical conversion coatings and plasma electrolytic oxidation (PEO) coatings were prepared on AZ31 Mg alloy for corrosion protection. Fe-containing impurity particles were found to be present at the positions where continuous gas evolution occurs in chloride and alkaline solutions. Corrosion of AZ31 Mg alloy was not initiated around the cathodic particles but occurred p...

  9. Graphene Nanoplatelets Based Protective and Functionalizing Coating for Stainless Steel.

    Science.gov (United States)

    Mondal, Jayanta; Kozlova, Jekaterina; Sammelselg, Väino

    2015-09-01

    Stainless steel is the most widely used alloy for many industrial and everyday applications, and protection of this alloy substrate against corrosion is an important industrial issue. Here we report a promising application of graphene oxide and graphene nanoplatelets as effective corrosion inhibitors for AISI type 304 stainless steel alloy. The graphene oxide and graphene coatings on the stainless steel substrates were prepared using spin coating techniques. Homogeneous and complete surface coverage by the graphene oxide and graphene nanoplatelets were observed with a high-resolution scanning electron microscope. The corrosion inhibition ability of these materials was investigated through measurement of open circuit potential and followed by potentiodymamic polarization analysis in aqueous sodium chloride solution before and after a month of immersion. Analyzed result exhibits effective corrosion inhibition for both substrates coated with graphene oxide or graphene nanoplatelets by increasing corrosion potential, pitting potential and decreasing passive current density. The corrosion inhibition ability of the coated substrates has not changed even after the long-term immersion. The result showed both graphene materials can be used as an effective corrosion inhibitor for the stainless steel substrates, which would certainly increase lifetime the substrate. However, long-term protection ability of the graphene coated susbtsrate showed somewhat better inhibition performance than the ones coated with graphene oxide. PMID:26716239

  10. Electrochemical Studies of Stainless Steel Corrosion in Peroxide Solutions

    OpenAIRE

    Singh, Ajay K; Vipin Chaudhary; Sharma, A.

    2012-01-01

    Pollution control measures have resulted in replacement of chlorine by peroxide as bleaching chemical. Change of chemical affects corrosion aspects, the suitability of existing plant metallurgy and materials of construction of bleach plants. Accordingly long term immersion and electrochemical corrosion tests were conducted on stainless steel 304L, 316L, 2205 and 6% Mo and mild steel in peroxide solutions of pH 10. The materials were tested for uniform corrosion, pitting and crevice corrosion ...

  11. Increasing of corrosion resistance of nitrided stainless steels

    International Nuclear Information System (INIS)

    The influence of C, Cr, Ni, V, Mo, Co, Al, Ti, Cu and Si on the corrosion resistance of the nitrided stainless steels has been studied alloying that ensures the post-nitriding corrosion resistance have been established. A lit-par-lit phase analysis of the nitrided 03Kh11N10M2T steel has been carried out; the reasons for the increased corrosion resistance of the low-carbon Cr-Ni steels following the nitriding are interpreted

  12. Crevice corrosion resistances of stainless steels in marine environments

    International Nuclear Information System (INIS)

    This paper studies the effects of minor elements on crevice corrosion resistances of stainless steels ranging from AISI 316 to the 6% molybdenum austenitic stainless steels in order to define an alloy composition suitable for seawater service and, in particular, for resistance to crevice corrosion. Overall, the results indicate the feasibility of significantly improving the corrosion resistance of the high-alloy austenitic stainless steels to the point where they would be suitable for seawater service

  13. Corrosion product release into sodium from austenitic stainless steel

    International Nuclear Information System (INIS)

    The results of radioactive and non-radioactive corrosion product release from austenitic stainless steel are discussed. Some release mechanism are described. It was found that corrosion of austenitic stainless steel in sodium is a complex process involving several mechanisms for the different alloy constituents. Many of the hypotheses of J.R. Weeks and H.S. Isaacs concerning the role of oxygen in corrosion of steels by sodium are confirmed

  14. Tribological and corrosion behaviors of carburized AISI 4340 steel

    Science.gov (United States)

    Thong-on, Atcharawadi; Boonruang, Chatdanai

    2016-01-01

    AISI 4340 steel is widely used in automotive and aircraft industries as gear components. In such applications, surface hardening processes such as carburizing are required in order to improve the life time of the components. There are many studies showing the tribological behavior of the carburized steel, but the corrosion behavior has not yet been clarified. This paper reports on both tribological and corrosion behaviors of the carburized AISI 4340 steel. Factor associated with carburizing, such as the quantities of deposited carbon, dissolved carbon, and formed Cr23C6 and Fe3C, affect the tribological and corrosion behaviors of the steel by improving hardness, friction, lubrication, and wear resistance; but corrosion resistance is reduced. The dissolved carbon affects the formation of the oxide layer of the carburized steel, by obstructing the continuous oxide layer formation and by decreasing the chromium content of the steel, leading to the decrease in the corrosion resistance of the steel.

  15. Corrosion and protection of aluminum alloys in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Nisancioglu Kemal [Department of Materials Technology, Norwegian University of Science and Technology, N-7491 Trondheim (Norway)

    2004-07-01

    The paper deals with pitting and uniform corrosion and effectiveness of cathodic protection in reducing these corrosion forms. In stagnant waters or presence of low flow rates, pitting may occur. However, pitting corrosion, driven by the Fe-rich cathodic intermetallic compounds, is often of superficial nature. The pits tend to passivate as a result of etching or passivation of the intermetallics with time. Cathodic protection is an effective way of preventing pitting. It also requires low current densities since the cathodic area, defined by the Fe-rich intermetallics, is small in contrast to steel, which is uniformly accessible to the cathodic reaction. Although thermodynamic calculations suggest possible instability of the oxide in slightly alkaline solutions, such as seawater, protective nature of the oxide in practice is attributed to the presence of alloying elements such as Mg and Mn. Thus, the passivity of both the aluminum matrix alloy (the anode) and the intermetallics (cathodes) have to be considered in evaluating the corrosion and protection of aluminum alloys. With increasing flow rate, the possibility of pitting corrosion reduces with increase in the rate of uniform corrosion, which is controlled by the flow dependent chemical dissolution of the oxide. Cathodic protection does not stop this phenomenon, and coatings have to be used. (authors)

  16. Influence of alloying elements on the corrosion properties of shape memory stainless steels

    International Nuclear Information System (INIS)

    Highlights: ? The corrosion properties of three Fe–Mn–Si–Cr–Ni–(Co) shape-memory stainless steels (SMSSs) were compared with those of a type 304 (SS 304) austenitic stainless steel. ? A considerably high Si content (about 40 at%) is present in the anodic passive films formed on SMSSs in 0.5 M H2SO4 solution. ? The high protectiveness of the anodic passive film formed on SMSSs in 0.5 M H2SO4 solution results from a protective film consisting of a (Fe, Cr)–mixed silicate. ? The SMSSs exhibited higher corrosion resistance than SS 304 in highly oxidizing environments. ? The SMSSs showed poor corrosion resistance in 3.5% NaCl solution compared to that of SS 304. - Abstract: The corrosion properties of three Fe–Mn–Si–Cr–Ni–(Co) shape memory stainless steels were studied based on X-ray photoelectron spectroscopy (XPS) analyses, immersion and polarization tests. The test results were compared with those of a type 304 austenitic stainless steel. The XPS analyses indicated substantial Si content in the anodic passive films formed on shape memory stainless steels in sulfuric acid solution and that the high protectiveness of these films results from a protective film consisting of a (iron, chromium)–mixed silicate. The corrosion rate of the shape memory stainless steels in boiling nitric acid solution was lower than that of austenitic stainless steel. The high silicon content was found to play an important role in the corrosion behavior of these shape memory alloys in highly oxidizing environments. Due to their high manganese content, the shape memory stainless steels showed poor corrosion behavior in 3.5% sodium chloride solution when compared with austenitic stainless steel.

  17. Corrosion of steel in concrete in cooling water walls. Report part 3 - Corrosion of steel in water saturated concrete

    International Nuclear Information System (INIS)

    It is a well known fact that for concrete structures exposed to water the splash zone exhibit the greatest risk for corrosion on the reinforcement. Chloride ions are enriched and the supply of oxygen is good. Below the water table reported corrosion damages are few. The threshold for chloride content is in most cases exceeded but the propagation rate is low due to slow diffusion rate of oxygen in water saturated concrete. Despite this, ongoing corrosion of reinforcement has been observed in cooling water systems at the Swedish nuclear power plants. The aim of this project has been to identify and qualitatively quantify the importance of different possible mechanisms involved in corrosion of reinforcement in water saturated concrete. This has been achieved by collecting experiences, literature survey, modelling, theoretical calculations, experimental investigations as well as field measurements. The investigations have resulted in several new findings. The following have been concluded: In water saturated concrete, without the existence of macro cells, the reinforcement corrodes in an active state but with a very low rate. This active corrosion proceeds independently of the chloride content of the concrete. The corrosion rate is low even with thin concrete cover and most probably even if the concrete has been leached. Nor does high velocity of the cooling water create serious attacks. Inspections have unveiled attacks of reinforcement corrosion in the splash zone, in walls externally exposed to air and in the vicinity to pumps. In the splash zone the attacks occur above the water level. The absence of a macro cell resulting in increased corrosion on parts below the water line is of subordinate importance and is judged being without practical influence. The corrosion takes place where the environmental conditions are optimal. The same is valid for walls externally exposed to air. The macro cell is of subordinate importance. In the vicinity of pumps, observed corrosion, is probably caused by galvanic corrosion as a consequence of incomplete cathodic protection of stainless steel surfaces within the pumps. Single rebar's being isolated from the rest of the reinforcement can be exposed to stray current corrosion if they are located close to a cathodically protected structure having a high demand for protective current. Concrete structures of greater extent can be exposed to stray current interference caused by high voltage direct current transmission lines located in the neighbourhood. Future installations of cathodic protection in extended culverts should not imply connection of separate parts to each other. The risk of alternating current corrosion is judged to be minimal. If it was not for the corrosion observed on reinforcement on the Oeland Bridge and in Gothenburg harbour, which until now has not been explained, corrosion should be possible to exclude in other positions than the splash zone, walls externally exposed to air and in the vicinity to unprotected structures of stainless steel

  18. Corrosion of the steel under thermal insulation - causes and means of prevention

    International Nuclear Information System (INIS)

    Corrosion problems of carbon and austenitic stainless steels under thermal insulation is discussed. Attention is paid to the high aggressiveness of environment especially with intermittent cycling down into hot water range due to frequent shutdowns. The availability of effective coatings protecting steel under thermal insulation is indicated, such as, epoxyphenolic, epoxy-novolac, inorganic zinc and aluminium aluminizing. (author)

  19. 78 FR 15376 - Determinations: Corrosion-Resistant Carbon Steel Flat Products From Germany and Korea

    Science.gov (United States)

    2013-03-11

    ...Determinations: Corrosion-Resistant Carbon Steel Flat Products From...countervailing duty order on corrosion-resistant carbon steel flat products from...antidumping duty orders on corrosion-resistant carbon steel flat products...

  20. Boric acid corrosion of low alloy steel

    International Nuclear Information System (INIS)

    In the last decade, the industry has been aware of a potential loss of coolant accident (LOCA) per the following scenario: primary water stress corrosion cracking (PWSCC) of a primary system component or weld leads to a coolant leak, the coolant corrodes a low alloy steel structural component (e.g., the reactor vessel (RV) or the reactor vessel head (RVH)), and corrosion degrades the pressure boundary leading to a loss of coolant accident. The industry has taken several steps to address this concern, including replacement of the most susceptible components (RVH replacement), enhanced inspection (both NDE of components and visual inspections for boric acid deposits), and safety analyses to determine appropriate inspection intervals. Although these measures are generally thought to have adequately addressed this issue, there have been some uncertainties in the safety analyses which the industry has sought to address in order to quantify the extent of conservatism in the safety analyses. Specifically, there has been some uncertainty regarding the rate of boric acid corrosion under various conditions which might arise due to a PWSCC leak and the extent to which boric acid deposits are retained near the leak under various geometries. This paper reviews the results of the Electric Power Research Institute (EPRI) Materials Reliability Program (MRP) boric acid corrosion (BAC) test programs conducted over the last 8 years, focusing on the most recent results of full-scale mockup testing of CRDM nozzle and bottom mounted nozzle (BMN) configurations. The main purpose of this presentation is to provide an overview of the latest understanding of the risk of boric acid corrosion as it is informed by the results of the testing conducted over the last eight years. The rate of boric acid corrosion has been found to be a function of many factors, including initial chemistry, the extent of concentration due to boiling, the temperature at which concentration takes place, the velocity of the coolant, and the concentration of dissolved oxygen. (author)

  1. Corrosion resistance of high-strength stainless maraging steels

    International Nuclear Information System (INIS)

    Investigated are corrosion resistance and electrochemical behaviour of low-carbon (0.03% C) steels of three groups: Fe-Cr-Ni, Fe-Cr-Co, Fe-Cr-Co-Ni additionally alloyed with one of the following elements: Mo, W, Si, Cu. The sample structure and character of corrosion fracture are evaluated metalographically. The steels have been subjected to heat treatment before testing. It is shown, that alloying of the steels investigated with molybdenum, tungsten, copper and silicon does not affect their resistance to corrosion cracking. In all the steels corrosion cracking takes place with formation of a great number of cracks, propagated along the grain boundaries or subboundaries of martensite grains. Copper and molybdenum increase effectively resistance to pitting corrosion, especially in cobalt-containing steels. Molybdenum also facilitates the steel passivation

  2. Influence of medium parameters and material parameters on the metal dissolution, the hydrogen consumption and the protective coating characteristics in the case of steel corrosion under increased CO sub 2 pressure. Zum Einfluss von Medien- und Werkstoffparametern auf die Metallaufloesung, Wasserstoffaufnahme und Deckschichteigenschaften bei der Stahlkorrosion unter erhoehten CO sub 2 -Druecken

    Energy Technology Data Exchange (ETDEWEB)

    Krieck-Defrain, M.

    1989-10-25

    The carbonic acid corrosion was studied against the background of material problems in natural gas production of steels with different crystalline structure and chemical composition (38Mn6, 34CrMo4, 30CrNiMo8, X10CrAl7, X10Cr13, X8Cr17) in the case of increased partial pressure. Experimental works handle three aspects: Effects on the composition, morphology and protective effect of corrosion product coatings of medium, material and phase-boundary parameters. In this way, boundary conditions and preconditions were to be determined for an increased susceptibility of the material to hole corrosion and flow-induced local corrosion. Hydrogen consumption of steels under the condition of CO{sub 2} high pressure corrosion, under mechanical load in particular. These works were related to the question of participation of corrosion hydrogen in the mechanism of CO{sub 2}-induced stress corrosion cracking. Determination of current density potential characteristics in steels with different alloy contents in the case of high CO{sub 2} partial-pressure. The effect of the chromium concentration on the electrochemical behavior of the materials was in the foreground of the interest. Cr-alloy steels are used increasingly under conditions of increased corrosiveness. (orig./MM).

  3. Evaluation of Performance of Grout Materials in Protection of Prestressing Steel

    Directory of Open Access Journals (Sweden)

    K. Kumar, M.S. Karthikeyan and N. Palaniswamy

    2008-03-01

    Full Text Available Prestressing cables are widely used in huge constructions like buildings and bridges. Corrosion of prestressing steel is more dangerous than the corrosion of reinforcing steel in concrete. Stress corrosion is propagated due to corrosion initiation in prestressing steel under stressed condition. Corrosion resistance of the prestressing steel depends upon the grout material. In this investigation three types of grout materials namely cement grout with non-shrinking admixture, polyurethane foam and epoxy grout were assessed for its suitability within the prestressing cable duct. The performance of grout materials to protect against prestressing steel corrosion was evaluated by different electrochemical techniques such as OCP measurements, anodic polarisation test and impressed voltage technique. The mechanical property of the different grout materials were test at room and elevated temperature. Among the three grouts, epoxy based grout system showed better corrosion resistance properties.

  4. Microbial-Influenced Corrosion of Corten Steel Compared with Carbon Steel and Stainless Steel in Oily Wastewater by Pseudomonas aeruginosa

    Science.gov (United States)

    Mansouri, Hamidreza; Alavi, Seyed Abolhasan; Fotovat, Meysam

    2015-07-01

    The microbial corrosion behavior of three important steels (carbon steel, stainless steel, and Corten steel) was investigated in semi petroleum medium. This work was done in modified nutrient broth (2 g nutrient broth in 1 L oily wastewater) in the presence of Pseudomonas aeruginosa and mixed culture (as a biotic media) and an abiotic medium for 2 weeks. The behavior of corrosion was analyzed by spectrophotometric and electrochemical methods and at the end was confirmed by scanning electron microscopy. The results show that the degree of corrosion of Corten steel in mixed culture, unlike carbon steel and stainless steel, is less than P. aeruginosa inoculated medium because some bacteria affect Corten steel less than other steels. According to the experiments, carbon steel had less resistance than Corten steel and stainless steel. Furthermore, biofilm inhibits separated particles of those steels to spread to the medium; in other words, particles get trapped between biofilm and steel.

  5. Activation of steel components for radiometric investigation of their corrosion resistance and of corrosion processes

    International Nuclear Information System (INIS)

    The method is described of using the activation of steel components by neutrons in a nuclear reactor for gamma spectrometric investigation of the kinetics of steel dissolution in a liquid corrosion medium. From the kinetic data (time dependence of the amount of dissolved steel components, time dependence of the rate of the dissolution of the different components, or the weight ratio of the dissolved components) it is possible to get an idea of the behavior of the investigated material in the given model corrosion conditions. Also presented are examples of the use of the method of the activation of steel components for investigation of the extraction process of the corrosion of alloy steels, for investigation of the effect of heat treatment on corrosion resistance of alloy steels and for investigation of the course of uneven steel corrosion. (author). 4 figs., 2 tabs

  6. Corrosion Protection of Electrically Conductive Surfaces

    Directory of Open Access Journals (Sweden)

    Jian Song

    2012-11-01

    Full Text Available The basic function of the electrically conductive surface of electrical contacts is electrical conduction. The electrical conductivity of contact materials can be largely reduced by corrosion and in order to avoid corrosion, protective coatings must be used. Another phenomenon that leads to increasing contact resistance is fretting corrosion. Fretting corrosion is the degradation mechanism of surface material, which causes increasing contact resistance. Fretting corrosion occurs when there is a relative movement between electrical contacts with surfaces of ignoble metal. Avoiding fretting corrosion is therefore extremely challenging in electronic devices with pluggable electrical connections. Gold is one of the most commonly used noble plating materials for high performance electrical contacts because of its high corrosion resistance and its good and stable electrical behavior. The authors have investigated different ways to minimize the consumption of gold for electrical contacts and to improve the performance of gold plating. Other plating materials often used for corrosion protection of electrically conductive surfaces are tin, nickel, silver and palladium. This paper will deal with properties and new research results of different plating materials in addition to other means used for corrosion protection of electrically conductive surfaces and the testing of corrosion resistance of electrically conductive surfaces.

  7. Improvement of barrier properties of a hybrid sol-gel coating by incorporation of synthetic talc-like phyllosilicates for corrosion protection of a carbon steel

    OpenAIRE

    Joncoux-Chabrol, Karine; Bonino, Jean-Pierre; Gressier, Marie; Menu, Marie-Joëlle; Pébère, Nadine

    2012-01-01

    Sol–gel coatings for corrosion protection of metals are a good alternative to toxic chromate treatments. The present work focussed on the incorporation of inorganic fillers in a sol–gel coating to improve the barrier properties of the film. Talc-like phyllosilicates obtained by hydrothermal synthesis at 160°C, 260°C and 350°C, called T160, T260 and T350 respectively, were selected as inorganic fillers. The synthetic materials showed talc lamellar structure but, in contrast with natural talc, ...

  8. Microbiological Corrosion in Low Carbon Steels

    Directory of Open Access Journals (Sweden)

    O. Medina–Custodio

    2009-01-01

    Full Text Available The Microbiologically Induced Corrosion affects several industries, such as oil industry where it is estimated that 20% to 30% pipes failures are related with microorganism . The chemical reactions generate ions transfer, this validate the use of electrochemical techniques for its analysis. Coupons submerged in a nutritional medium with presence and absence of three different microorganisms during two periods, 48 hours and 28 days we restudied. Polarization resistance (Rp and Electrochemical Impedance Spectroscopy (EIS techniques we re applied to determine the corrosivity of the systems. The results show a greater corrosive effect of abiotic system, this indicates a microorganisms protection effect to the metal, opposite to the first hypothesis. This result was ratified observing surfaces coupons by using Scanning Electron Microscopy (SEM technique. A possible mechanism based on Evans – Tafel graph is proposed to explain inhibitor microorganism effect.

  9. New Sol-gel Formulations to Increase the Barrier Effect of a Protective Coating Against the Corrosion and Wear of Galvanized Steel

    Scientific Electronic Library Online (English)

    Sandra Raquel, Kunst; Henrique Ribeiro Piaggio, Cardoso; Lilian Vanessa Rossa, Beltrami; Claúdia Trindade, Oliveira; Tiago Lemes, Menezes; Jane Zoppas, Ferreira; Célia de Fraga, Malfatti.

    2015-02-01

    Full Text Available This study proposes a new pretreatment method that uses alkoxide precursors with a plasticizing agent; the purpose of this study is to improve the electrochemical and mechanical properties of a galvanized steel surface. Galvanized steel was covered with a hybrid film obtained from a sol that consist [...] ed of two alkoxide precursors, 3 - (trimethoxysilylpropyl) methacrylate (TMSM) and tetraethoxysilane (TEOS), with nitrate cerium in a concentration of 0.01 M and a polyethylene glycol (PEG) plasticizer. The hybrid coatings were obtained by dip-coating method with various concentrations of plasticizer (0, 20, 40 and 60 g.L-1). The hybrid films were analyzed by scanning electron microscopy (SEM), profilometry, contact angle measurements, a tribometer with the type-setting ball on the plate and electrochemical tests. The addition of the plasticizer into the hybrid films improves the corrosion resistance behavior compared to the sample without the plasticizer. The addition of 20 g.L-1 of plasticizer showed the best performance in the electrochemical tests. The mechanical behavior results indicated that higher PEG concentrations resulted in films with enhanced durability.

  10. Influence of burnishing on stress corrosion cracking susceptibility of duplex steel

    Directory of Open Access Journals (Sweden)

    J. ?abanowski

    2006-09-01

    Full Text Available Purpose: of the current study was to investigate the usability of burnishing-inducted surface enhancement method for improve the stress corrosion cracking resistance of duplex stainless steel.Design/methodology/approach: The surface layers upon round in cross section specimens were performed through burnishing treatment. Corrosion tests were performed with the use of Slow Strain Rate Test technique in inert (glycerin and aggressive (boiling 35% MgCl2 solution environments.Findings: It was shown that burnishing treatment increases corrosion resistance of the steel. Stress corrosion cracking resistance depends on the magnitude of cold work at surface layers. High level of cold work decreases corrosion resistance.Research limitations/implications: This study does not indicate the optimum stress level and stress distribution in surface layers for the best corrosion resistance. It is necessary to continue the research to determine burnishing parameters for demanded properties of duplex steel surface layers.Practical implications: The burnishing treatment can significantly improve stress corrosion resistance of specified parts of chemical installations working in the contact with aggressive media. Such parts as valve parts or propeller shafts can be successfully protected against corrosion attack.Originality/value: Burnishing surface enhancement for constructional parts made of duplex stainless steels exposed to corrosive environments has not been reported in literature. Application of this technology can increase life-time of chemical installation devices and improve their reliability.

  11. Microbially induced corrosion of carbon steel in deep groundwater environment.

    Science.gov (United States)

    Rajala, Pauliina; Carpén, Leena; Vepsäläinen, Mikko; Raulio, Mari; Sohlberg, Elina; Bomberg, Malin

    2015-01-01

    The metallic low and intermediate level radioactive waste generally consists of carbon steel and stainless steels. The corrosion rate of carbon steel in deep groundwater is typically low, unless the water is very acidic or microbial activity in the environment is high. Therefore, the assessment of microbially induced corrosion of carbon steel in deep bedrock environment has become important for evaluating the safety of disposal of radioactive waste. Here we studied the corrosion inducing ability of indigenous microbial community from a deep bedrock aquifer. Carbon steel coupons were exposed to anoxic groundwater from repository site 100 m depth (Olkiluoto, Finland) for periods of 3 and 8 months. The experiments were conducted at both in situ temperature and room temperature to investigate the response of microbial population to elevated temperature. Our results demonstrate that microorganisms from the deep bedrock aquifer benefit from carbon steel introduced to the nutrient poor anoxic deep groundwater environment. In the groundwater incubated with carbon steel the planktonic microbial community was more diverse and 100-fold more abundant compared to the environment without carbon steel. The betaproteobacteria were the most dominant bacterial class in all samples where carbon steel was present, whereas in groundwater incubated without carbon steel the microbial community had clearly less diversity. Microorganisms induced pitting corrosion and were found to cluster inside the corrosion pits. Temperature had an effect on the species composition of microbial community and also affected the corrosion deposits layer formed on the surface of carbon steel. PMID:26257707

  12. Microbially induced corrosion of carbon steel in deep groundwater environment

    Science.gov (United States)

    Rajala, Pauliina; Carpén, Leena; Vepsäläinen, Mikko; Raulio, Mari; Sohlberg, Elina; Bomberg, Malin

    2015-01-01

    The metallic low and intermediate level radioactive waste generally consists of carbon steel and stainless steels. The corrosion rate of carbon steel in deep groundwater is typically low, unless the water is very acidic or microbial activity in the environment is high. Therefore, the assessment of microbially induced corrosion of carbon steel in deep bedrock environment has become important for evaluating the safety of disposal of radioactive waste. Here we studied the corrosion inducing ability of indigenous microbial community from a deep bedrock aquifer. Carbon steel coupons were exposed to anoxic groundwater from repository site 100 m depth (Olkiluoto, Finland) for periods of 3 and 8 months. The experiments were conducted at both in situ temperature and room temperature to investigate the response of microbial population to elevated temperature. Our results demonstrate that microorganisms from the deep bedrock aquifer benefit from carbon steel introduced to the nutrient poor anoxic deep groundwater environment. In the groundwater incubated with carbon steel the planktonic microbial community was more diverse and 100-fold more abundant compared to the environment without carbon steel. The betaproteobacteria were the most dominant bacterial class in all samples where carbon steel was present, whereas in groundwater incubated without carbon steel the microbial community had clearly less diversity. Microorganisms induced pitting corrosion and were found to cluster inside the corrosion pits. Temperature had an effect on the species composition of microbial community and also affected the corrosion deposits layer formed on the surface of carbon steel. PMID:26257707

  13. Crevice corrosion properties of stainless steels in diluted sea water

    International Nuclear Information System (INIS)

    Experiments of crevice corrosion occurrence condition, initiation rate and propagation rate were conducted for several kind of stainless steels used for feedwater-condenser system of boiling water reactor. The occurrence condition was obtained from comparison of crevice corrosion potential and corrosion potential as a function of kind of steel and chloride ion concentration is parameters. Threshold chloride concentration of crevice corrosion for SUS304L, SUS316L and SCS19A was 500ppm. The value for SUS403 was 15ppm. Constant potential test was conducted in order to obtain corrosion initiation time from current-time profile, corrosion depth from observation of the test specimen. Dependency of crevice corrosion initiation time on temperature was obtained in 6000ppm chloride diluted sea water. Maximum corrosion depth was obtained from inspection of each specimen then compared with corrosion propagation time. (author)

  14. Corrosion inhibition in 2.0 M sulfuric acid solutions of high strength maraging steel by aminophenyl tetrazole as a corrosion inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Sherif, El-Sayed M., E-mail: emsherif@gmail.com [Center of Excellence for Research in Engineering Materials (CEREM), Advanced Manufacturing Institute, King Saud University, PO. Box 800, Al-Riyadh 11421 (Saudi Arabia); National Research Centre (NRC), Electrochemistry and Corrosion Laboratory, Department of Physical Chemistry, National Research Centre (NRC), Dokki, 12622 Cairo (Egypt)

    2014-02-15

    The corrosion of high strength maraging steel after varied immersion times in concentrated solution, 2.0 M, of sulfuric acid has been investigated. The work was also extended to study the effect of 5-(3-aminophenyl)-tetrazole (APTA) on the inhibition of the steel corrosion. The study has been carried out using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and scanning electron microscope (SEM) along with energy dispersive X-ray analyzer (EDX) investigations. EIS spectra showed that the corrosion and polarization resistances decrease with increasing the immersion time of the steel before measurement and increase in the presence of APTA and the increase of its concentration. Polarization data agreed with the EIS measurements and indicated that the increase of immersion time increases the corrosion of steel by increasing its corrosion current and corrosion rate and lowering its polarization resistance. On the other hand, the addition of APTA and the increase of its concentration minimized the corrosion of steel through decreasing the corrosion current and corrosion rate and increasing the polarization resistance at all exposure test periods. SEM and EDX investigations confirmed that the inhibition of the maraging steel in the 2.0 M H{sub 2}SO{sub 4} solutions is achieved via the adsorption of the APTA molecules onto the steel protecting its surface from being dissolved easily.

  15. Corrosion inhibition in 2.0 M sulfuric acid solutions of high strength maraging steel by aminophenyl tetrazole as a corrosion inhibitor

    International Nuclear Information System (INIS)

    The corrosion of high strength maraging steel after varied immersion times in concentrated solution, 2.0 M, of sulfuric acid has been investigated. The work was also extended to study the effect of 5-(3-aminophenyl)-tetrazole (APTA) on the inhibition of the steel corrosion. The study has been carried out using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and scanning electron microscope (SEM) along with energy dispersive X-ray analyzer (EDX) investigations. EIS spectra showed that the corrosion and polarization resistances decrease with increasing the immersion time of the steel before measurement and increase in the presence of APTA and the increase of its concentration. Polarization data agreed with the EIS measurements and indicated that the increase of immersion time increases the corrosion of steel by increasing its corrosion current and corrosion rate and lowering its polarization resistance. On the other hand, the addition of APTA and the increase of its concentration minimized the corrosion of steel through decreasing the corrosion current and corrosion rate and increasing the polarization resistance at all exposure test periods. SEM and EDX investigations confirmed that the inhibition of the maraging steel in the 2.0 M H2SO4 solutions is achieved via the adsorption of the APTA molecules onto the steel protecting its surface from being dissolved easily.

  16. Thin film corrosion protecting coatings for high temperature fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Wind, J.; Nitschke, F.; Meyer, M. [Daimler-Benz AG, Berlin (Germany). Forschung Technikumfeld

    1997-12-31

    One of the major problems in high temperature fuel cells (molten carbonate fuel cells and solid oxide fuel cells) is the corrosion of metallic components. A method to solve this problem was proposed. Stainless steel components are usually protected by coatings which tend to diffuse into the substrate. This results in reduced protection or even a complete loss of protection. It was suggested that a diffusion barrier applied between the coating and substrate could solve this problem. The corrosion of steel sheet material coated with a diffusion layer and a corrosion protecting layer was studied. Materials studied included the refractory metals molybdenum, tungsten, chromium nitride and titanium nitride. Auger electron spectroscopy (AES) depth profiles were described for samples coated with each of these materials as a diffusion barrier and with a nickel layer on top before diffusion. AES revealed a very low diffusion of components from the coatings to the substrate and vice versa. Metallographic cross sections also showed that the system prevents corrosion almost completely. 9 refs., 9 figs.

  17. Fire protection of steel structures

    OpenAIRE

    Krivtcov, Artem

    2014-01-01

    The purpose of the work was to make a simple program for constructors to choose and check the different options of fire protection of steel structures and to analyze the results of it. The idea of the program was to include all the factors influencing the result: the fire resistant class of the structure, the load, the geo-metrical characteristics, the type of work of a structure and the type of steel. The calculation was made according to the Russian regulations: SP 16.13330.2011. “Steel ...

  18. Atmospheric Corrosion on Steel Studied by Conversion Electron Moessbauer Spectroscopy

    International Nuclear Information System (INIS)

    In order to investigate initial products on steel by atmospheric corrosion, conversion electron Moessbauer measurements were carried out at temperatures between 15 K and room temperature. From the results obtained at low temperatures, it was found that the corrosion products on steel consisted of ferrihydrite.

  19. Bimetallic corrosion of high-strength stainless steels

    International Nuclear Information System (INIS)

    Through the studied on corrosion of VNS-2, VNS-59, EhI961, EhP517, EhP866, 20Kh13, 40Kh13, 95Kh18 and EhI474 in salt fog and 3 % NaCl solution it is established that contact with titanium alloys does not intensify the corrosion; contact with copper alloys strengthens the corrosion of steels excluding the VNS-2 and VNS-59 steels. Contacts with titanium and copper alloys do not reduce the resistance of the steels under consideration against corrosion cracking

  20. Microstructure and corrosion behaviour of plasma-nitrocarburized sintered steel

    Energy Technology Data Exchange (ETDEWEB)

    Borges, P.C. [CEFET-PR, Departmento Academico de Mecanica, Av. Sete de Stembro 3165, Curitiba, PR, 80230-901 (Brazil); Martinelli, A.E. [Universidade Federal do Rio Grande do Norte, Departemento de Engenharia Mecanica, Lagoa Nova Campus, Natal, RN, 59072-970 (Brazil); Franco, C.V. [Universidade Federal de Santa Catarina, Departamento de Quimica, Trindade Campus, Florianopolis, SC 88040-900 (Brazil)

    2004-08-01

    Powder characteristics and manufacturing processes determine the microstructure, and therefore, the physical, chemical, and mechanical properties of sintered steels. In particular, porosity and corrosion resistance are intimately related, since the contact area between substrate and electrolyte significantly affects the corrosion resistance of sintered steels. This study addresses the effect of powder characteristics and pressing parameters on the microstructure and corrosion resistance of low-carbon sintered and sintered/plasma-nitrocarburized steel. The results indicated that the corrosion resistance increased with increasing density and decreasing specific surface area. Additionally, plasma-nitrocarburizing was highly effective in coating open pores of the material. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

  1. Steel corrosion in ammonia solutions studied by Moessbauer spectrometry

    International Nuclear Information System (INIS)

    The corrosive action of diluted ammonia solutions has been thoroughly studied until 90s. A particular interest towards studying it after this time arisen from problems relating to environment protection. We have initiated a programme which involves the study of steel samples in ammoniac solutions. The steel samples were obtained from industrial Fe-C steel with C of low concentration. The surface of the samples was diamond polished, subsequently degreased and desiccated. The corrosion process of the samples was performed in an electrolytic cell with diluted ammonia solutions of concentration ranging within 10-1 - 10-4 N. Moessbauer measurements were performed at room temperature in the transmission (TMS) and conversion electron spectroscopy (CEMS) using a conventional constant-acceleration spectrometer with a 57 Co-Rh source. The TMS spectrum shows the presence of a single sextet: ?-iron. The best fit of the CEMS spectra uses an addition wide line to the sextet. The parameters of the wide line correspond to a non-stoichiometric oxide with (probably) small particles. Also the line parameters prove that we have studied the early stage of the corrosion process. All CEMS spectra show that on the surface the directions of the ?-ray and the magnetic moments are nearly perpendicular. There is a magnetic anisotropy on the surface of the samples, which remains even in the corroded samples. In contrast TMS spectrum shows that in the interior of the sample the magnetic moments are in a random arrangement. The result of the corrosion is the layer appearance (non-stoichiometric iron oxide) on the sample surface. The layer thickness increases with the change of the NH3 concentration from 10-1 to 10-4 N. (authors)

  2. Boric acid corrosion protection program for pump and valve fasteners

    International Nuclear Information System (INIS)

    It has been recognized that the boric acid corrosion wastage of pump and valve fasteners is mainly a maintenance problem. Therefore, the nuclear utilities of pressurized water reactor (PWR) power plants can prevent this damage by implementing appropriate fastener steel replacement and extended inspections to detect and correct the cause of leakage. A 3-Phase Corrosion Protection Program is presented for implementation based on system operability, outage related accessibility and cost of fastener replacement versus maintenance frequency increase. A selection criteria for fastener material is indicated based on service limitation: metal temperature and preloading. (orig.)

  3. Boric acid corrosion protection program for pump and valve fasteners

    Energy Technology Data Exchange (ETDEWEB)

    Moisidis, N.; Popescu, M.; Ratiu, M. (ABB Impell Corp., San Ramon, CA (United States))

    1992-01-01

    It has been recognized that the boric acid corrosion wastage of pump and valve fasteners is mainly a maintenance problem. Therefore, the nuclear utilities of pressurized water reactor (PWR) power plants can prevent this damage by implementing appropriate fastener steel replacement and extended inspections to detect and correct the cause of leakage. A 3-Phase Corrosion Protection Program is presented for implementation based on system operability, outage related accessibility and cost of fastener replacement versus maintenance frequency increase. A selection criteria for fastener material is indicated based on service limitation: metal temperature and preloading. (orig.).

  4. Corrosion protection method by neutral treatment for boilers

    International Nuclear Information System (INIS)

    The corrosion protection method by neutral treatment has been applied in Europe mainly for boilers and nuclear reactors instead of existing all volatile treatment. The cause of corrosion of steel and copper in water and the effect of neutral treatment, that is the effect of protection film of magnetite in steel and cuprous oxide in copper alloy, are explained with the characteristic figure of PH, electromotive force and chemical formula. The experience of applying this neutral treatment to the Wedel thermal power plant and the system flow sheet, the water treatment equipment, relating instrumentations and the water examination are described in detail. Hydrogen peroxide is injected in this neutral treatment. The comparison between the existing water treatment and the neutral treatment and their merits and demerits are explained. (Nakai, Y.)

  5. The effect of ion implantation on the resistance of 316L stainless steel to crevice corrosion

    International Nuclear Information System (INIS)

    The results of an investigation of the influence of aluminium, titanium and scandium implantation on the electrochemical and chemical crevice corrosion behaviour of 316L stainless steel are presented and discussed. Ion implantation, in addition to improving markedly the protective quality of the passive film at the free corrosion potential, greatly increases the resistance of 316L stainless steel to crevice corrosion in both neutral NaCl and acidic FeCl3 solutions. A moderate decrease in pitting resistance is possibly due to coverage effect of implanted species on the surface molybdenum constituent. (Auth.)

  6. To the corrosion of austenitic steel in sodium loops

    International Nuclear Information System (INIS)

    This paper investigates whether it is possible to predict corrosion effects for austenitic steels exposed to liquid sodium with an analytical diffusion model. The comparison between experimental measurements of corrosion and calculated corrosion effects is described. The work presented attempts to demonstrate that the sodium mass transfer phenomena can be described with a diffusion model. 40 refs

  7. Improved corrosion protection of powered roof supports

    Energy Technology Data Exchange (ETDEWEB)

    Griffiths, J.R.; Talks, M.G.; Trudgeon, M.A.

    1988-12-01

    Corrosion damage to equipment has required British Coal to spend considerable sums of money on refurbishing. The corrosion protection currently applied during equipment manufacture is influenced more by initial costs than by total life cost. This paper describes a major corrosion project which was conducted to assess metallic, paint and plastic coatings for the protection of powered roof support components. The project involved evaluation of coatings in the laboratory and on coal face installations, estimating the total life costs and deciding upon the most suitable coatings for future use. About 16000 components were involved in the field trials: the costs and production schedules relating to the protective systems were thus representative of large scale use. Forty two protective coatings were used in the underground field trials, with varying degrees of success. The results enabled an improved corrosion protection scheme to be produced whose use should result in substantial savings to British Coal. 6 refs., 6 figs., 6 tabs.

  8. Initial Atmospheric Corrosion of Carbon Steel in Industrial Environment

    Science.gov (United States)

    Han, Wei; Pan, Chen; Wang, Zhenyao; Yu, Guocai

    2015-02-01

    The initial corrosion behavior of carbon steel subjected to Shenyang industrial atmosphere has been investigated by weight-loss measurement, scanning electron microscopy observation, x-ray diffraction, auger electron spectroscopy, and electron probe microanalysis. The experimental results reveal that the corrosion kinetics of the initial corrosion of carbon steel in industrial atmosphere follows empirical equation D = At n , and there is a corrosion rate transition from corrosion acceleration to deceleration; the corrosion products are composed of ?-FeOOH, ?-FeOOH, Fe3O4, as well as FeS which is related to the existence of sulfate-reducing bacteria in the rust layers. The effect of dust particles on the corrosion evolution of carbon steel has also been discussed.

  9. Calculation of minimum cathodic protection potential of carbon steel in soil using cathodic polarization curve

    International Nuclear Information System (INIS)

    Consideration is given to the simple method for calculating the minimal protective potential and corrosion rate of steel in soil using cathode curve and the value of free corrosion potential. The suggested electrochemical method for calculating corrosion rate at cathode polarization requires the minimal number of experimental data (cathode polarization curve and E cor value) and calculation procedure is very simple

  10. The anaerobic corrosion of carbon steel in concrete

    International Nuclear Information System (INIS)

    This is the final report of a 2 year programme aimed at (1) determining the rate of anaerobic corrosion of steel in concrete, (2) investigating the nature of the corrosion products formed on carbon steel embedded in cementitious material under anaerobic conditions and (3) evaluating the effect of hydrogen over-pressures on the rate of anaerobic corrosion. All experiments have been carried out at temperatures in the range 20-300C, ie ambient conditions. 4 refs.; 19 figs.; 6 tabs

  11. Irradiated accelerated corrosion of stainless steel

    International Nuclear Information System (INIS)

    Type 316L stainless steel was exposed to a simulated PWR environment with in-situ proton irradiation to investigate the effect of simultaneous irradiation and corrosion. To enable these experiments, a dedicated beamline was constructed to transport a 3.2 MeV proton beam from a tandem accelerator, through the sample that also acts as the window between the beamline vacuum and a corrosion cell designed to flow primary water at 320 C. degrees and 13.1 MPa. Experiments were conducted on 316L stainless steel samples which were irradiated for 24 hours in 320 C. degrees water with 3 ppm H2, at dose rates of 7*10-6 dpa/s and 7*10-7 dpa/s, for 4, 24, and 72 hours. A dual-layer oxide formed on the samples, with an inner layer rich in Cr with Fe and Ni content, and an outer layer of Fe oxides. Samples were characterized with TEM (Transmission Electron Microscopy), EDS, and Raman spectroscopy to determine the effect of irradiation. Irradiated samples were found to have a thinner and more porous inner oxide which was deficient in chromium. The outer oxide was found to have significant hematite content, suggesting that irradiation led to an increase in ECP (Electro-Chemical Potential) at the oxide-solution interface, causing accelerated dissolution of the oxide under irradiation. (authors)

  12. Corrosion of Steel in Concrete – Potential Monitoring and Electrochemical Impedance Spectroscopy during Corrosion Initiation and Propagation

    DEFF Research Database (Denmark)

    Küter, Andre; Mason, Thomas O.

    2005-01-01

    A reinforced mortar specimen that allows potential measurements and electrochemical impedance spectroscopy (EIS) immediately after preparation was designed and tested. The specimen consists of a mortar cylinder with a central rebar and a concentric arrangement of embedded Ru/Ir activated titanium wires. The wires can act as both reference and counter electrode during EIS and, thus, no external electrode is required. The defined geometry solves reproducibility problems involved with application of an external reference electrode for EIS. Changes of the electromotive force (EMF) between rebar and titanium wires can be monitored immediately after preparation. The wire arrangement also allows investigation of local changes in the bulk mortar by EIS or by measuring the potential development of the titanium wires versus an external standard electrode. The specimen design was evaluated in an investigation on the effect of the steel quality and the steel surface properties on initiation and propagation of chloride-induced reinforcement corrosion. Besides untreated (as received) carbon rebars and stainless rebars, selected surface treatments and galvanization were investigated. The surface treatments included grit blasting, electrochemical and hydrochloric acid cleaning (HCl) as well as weathering. The results indicate that the investigated treatments of the carbon steel surface have no major effect on the initiation period, which was approximately 20 days under the actual conditions. The galvanized rebar appears to be protected throughout the experimental period to date (200 days), whereas active corrosion of the stainless steel appeared to be initiated after 100 days exposure.

  13. Corrosion Behavior of High-Strength Bainitic Rail Steels

    Science.gov (United States)

    Moon, A. P.; Sangal, S.; Layek, S.; Giribaskar, S.; Mondal, Kallol

    2015-04-01

    The present work discusses corrosion behavior of newly developed bainitic steels made by isothermal heat treatment of a new steel composition (0.71 pct C, 1.15 pct Mn, 0.20 pct Ni, 0.59 pct Cr, 0.40 pct Cu, 0.35 pct Si, 0.026 pct S, 0.027 pct P, and rest Fe (weight percent)). Corrosion behavior of the pearlitic steel made by normalization is also studied. Electrochemical polarization and salt fog tests are carried out in 0.6 M NaCl. Steel rusts after salt fog tests are analyzed. Modified composition, finer microstructures, and compact rust morphology attribute to better corrosion resistance of the bainitic steels. Corrosion mechanisms for the pearlitic and bainitic steels are discussed.

  14. Experiencies of corrosion and corrosion protection in seawater-cooling systems in the Nordic countries

    International Nuclear Information System (INIS)

    This report summarizes the experience of the corrosion resistance of pumps, heat exchangers, valves, and pipings in different seawater-cooling system. For pumps and heat exchangers the experience has been so extensive that a clear picture of todays status can be given. Owing to more scanty data concerning valves and pipes the survey of the corrosion in these components is less well substantiated. The most common pumps in the cooling systems of power stations are vertically extended shaft pumps. To counteract corrosion on column and casing with organic surface coating and on stainless steel shafts and impellers under shutdown conditions, these should be provided with internal and external cathodic protection. The experience of tin and aluminium bronzes in impellers and shafts in such pumps has been so poor - erosion and cavitaion damage - that a change has usually been made to preferentially ferritic-austenitic Mo-alloyd stainless steels. The combination of stainless steel/Ni-Resist 2 D has been found unsatisfactory owing to the occurrence of galvanic corrosion on the latter material. For heat exchangers, titanium has proved to be far and away the best choice. In the optimal blanket solution for a titanium heat exchangers the tubes are seal-welded to tube sheets of explosion-bonded titanium clad steel. For retubing of old condensers a similar procedure with tubes of high-alloy stainless steel in tube sheets of stainless clad steel is of economic interest. The effect of chlorination of the cooling water, however, remains to be clarified before such a procedure can be unreservedly recommended. Pipings of rubber-lined carbon steel or with thick coatings of solvent-free opoxy resin have shown very good corrosion resistance. Tar-epoxy-resin-coated pipes, however, should usually be provided with internal cathodic protection. Cement-lined carbon steel pipes are used with varying results in the offshore industry. Recently, however, pipes of the high slloy stainless steel 254 SMO have also come into use for similar purposes. (Author)

  15. Aminopyrimidine derivatives as inhibitors for corrosion of 1018 carbon steel in nitric acid solution

    International Nuclear Information System (INIS)

    The effect of some aminopyrimidine derivatives on the corrosion of 1018 carbon steel in 0.05 M HNO3 solution was studied using weight loss and polarization techniques. The percentage inhibition efficiency was found to increase with increasing concentration of inhibitor and with decreasing temperature. The addition of KI to aminopyrimidine derivatives enhanced the inhibition efficiency due to synergistic effect. The inhibitors are adsorbed on the steel surface according to Temkin isotherm. Some thermodynamic functions were computed and discussed. It was found that the aminopyrimidine derivatives provide a good protection to steel against pitting corrosion in chloride containing solutions

  16. Fabrication of superhydrophobic textured steel surface for anti-corrosion and tribological properties

    Science.gov (United States)

    Zhang, Hongmei; Yang, Jin; Chen, Beibei; Liu, Can; Zhang, Mingsuo; Li, Changsheng

    2015-12-01

    We describe a simple and rapid method to fabricate superhydrophobic textured steel surface with excellent anti-corrosion and tribological properties on S45C steel substrate. The steel substrate was firstly ground using SiC sandpapers, and then polished using diamond paste to remove scratches. The polished steel was subsequently etched in a mixture of HF and H2O2 solution for 30 s at room temperature to obtain the textured steel surface with island-like protrusions, micro-pits, and nano-flakes. Meanwhile, to investigate the formation mechanism of the multiscale structures, the polished steel was immersed in a 3 wt% Nital solution for 5 s to observe the metallographic structures. The multiscale structures, along with low-surface-energy molecules, led to the steel surface that displayed superhydrophobicity with the contact angle of 158 ± 2° and the sliding angle of 3 ± 1°. The chemical stability and potentiodynamic polarization test indicated that the as-prepared superhydrophobic surface had excellent corrosion resistance that can provide effective protection for the steel substrate. The tribological test showed that the friction coefficient of the superhydrophobic surface maintained 0.11 within 6000 s and its superhydrophobicity had no obvious decrease after the abrasion test. The theoretical mechanism for the excellent anti-corrosion and tribological properties on the superhydrophobic surface were also analyzed respectively. The advantages of facile production, anti-corrosion, and tribological properties for the superhydrophobic steel surface make it to be a good candidate in practical applications.

  17. Further studies of the anaerobic corrosion of steel in bentonite

    International Nuclear Information System (INIS)

    In the horizontal emplacement concept (KBS-3H) for the disposal of radioactive waste, which is being developed in Sweden and Finland, copper canisters with cast iron inserts will be surrounded by bentonite buffer and mounted in perforated carbon steel support structures in boreholes within the bedrock. The groundwater will be reducing, leading to anaerobic corrosion of the ferrous material. It is important to understand both the effect of bentonite on the corrosion behaviour of the steel and the effect of the corrosion products on the performance of the bentonite. Previous work on the corrosion of steel in bentonite was extended to investigate a wider range of conditions, including the possible effects of alkaline plumes released from concrete support structures and the effect of chloride concentration and temperature on the corrosion rate of steel in bentonite. Corrosion rates were measured by collecting hydrogen produced by the anaerobic corrosion of iron. In addition, a range of analytical techniques was applied to study the composition and morphology of the corrosion products and the distribution and chemical state of the iron released into the bentonite. Comparison was also made between corrosion in compacted bentonite and artificial bentonite porewater. In the presence of bentonite, the corrosion product layer was relatively thin compared to fully aqueous conditions, probably because the ferrous ions released by corrosion exchanged with the bentonite interlayer or attached to the surface of the bentonite grains, rather than forming a separate iron oxide phase. (author)

  18. Effect of chloride content of molten nitrate salt on corrosion of A516 carbon steel.

    Energy Technology Data Exchange (ETDEWEB)

    Bradshaw, Robert W.; Clift, W. Miles

    2010-11-01

    The corrosion behavior of A516 carbon steel was evaluated to determine the effect of the dissolved chloride content in molten binary Solar Salt. Corrosion tests were conducted in a molten salt consisting of a 60-40 weight ratio of NaNO{sub 3} and KNO{sub 3} at 400{sup o}C and 450{sup o}C for up to 800 hours. Chloride concentrations of 0, 0.5 and 1.0 wt.% were investigated to determine the effect on corrosion of this impurity, which can be present in comparable amounts in commercial grades of the constituent salts. Corrosion rates were determined by descaled weight losses, corrosion morphology was examined by metallographic sectioning, and the types of corrosion products were determined by x-ray diffraction. Corrosion proceeded by uniform surface scaling and no pitting or intergranular corrosion was observed. Corrosion rates increased significantly as the concentration of dissolved chloride in the molten salt increased. The adherence of surface scales, and thus their protective properties, was degraded by dissolved chloride, fostering more rapid corrosion. Magnetite was the only corrosion product formed on the carbon steel specimens, regardless of chloride content or temperature.

  19. Corrosion of SUS304 stainless steel in oxalic acid solution

    International Nuclear Information System (INIS)

    The corrosion rate of oxidized and unoxidized SUS304 stainless steel was measured in 0.1M oxalic acid at 80degC under the potentiostatically polarized conditions. The dissolved amounts of Fe, Cr and Ni were determined by atomic absorption analysis after 166 min of polarization as a function of the potential. The corrosion potential and the sweep potentiostatic polarization curve were also measured in the same solution. The unoxidized specimen was severely attacked at the cathodic potential between -200 and -700 mV vs Ag-AgCl. Similar cathodic corrosion was also found, but with a decreased dissolution rate, for oxidized specimens. Since the corrosion potential of the alloy situated nearly at the boundary of active passive transition, both specimens frequently suffered localized attack due to insufficient passivation during spontaneous immersion. The dissolution rate of the surface oxide was slightly effected by the electrode potential within the active and the passive regions. Therefore, weakly anodic polarization is desirable for the dual purposes of the effective dissolution of surface oxide and the protection of substrate alloy surface. (author)

  20. Corrosion of steel and copper tubes for water supply in buildings

    International Nuclear Information System (INIS)

    Corrosion test of steel-, galvanized steel- and copper-tube for water supply in buildings was carried out by simulation method. These samples were tested in the cold water and 80 deg C hot water with a condition of real situation. Basic data for estimating the life-time of each tubes was obtained from the test. According to the analysis of tap waters of major cities in Korea, most of tap waters have a good quality, but the values of Langelier Saturation Index (Is) were in the range of -1.0 to -3.4 and values of pH were about 6. So the formation of protective film by calcium carbonate salts may not be occurred and corrosion of these tubes can be progressed in this condition. Corrosion rates of steel-, galvanized steel- and copper-tube obtained from field test in cold water were 17.9 mdd, 1.02 mdd and 0.67 mdd, respectively, and were nearly constant with a test time. In hot water of 80 deg C, corrosion rate of steel-and galvanized steel-tube were about 5 times of that measured in cold water and increased with velocity of flowing water. But, in copper tube, corrosion rate was lower than that obtained in cold water and the value obtained at velocity of 0.65m/s was lower than that at 0.3 m/s. The results were discussed on the point of protective film formation. (Author)

  1. Materials corrosion and protection at high temperatures

    International Nuclear Information System (INIS)

    This book was made from the lectures given in 2010 at the thematic school on 'materials corrosion and protection at high temperatures'. It gathers the contributions from scientists and engineers coming from various communities and presents a state-of-the-art of the scientific and technological developments concerning the behaviour of materials at high temperature, in aggressive environments and in various domains (aerospace, nuclear, energy valorization, and chemical industries). It supplies pedagogical tools to grasp high temperature corrosion thanks to the understanding of oxidation mechanisms. It proposes some protection solutions for materials and structures. Content: 1 - corrosion costs; macro-economical and metallurgical approach; 2 - basic concepts of thermo-chemistry; 3 - introduction to the Calphad (calculation of phase diagrams) method; 4 - use of the thermodynamic tool: application to pack-cementation; 5 - elements of crystallography and of real solids description; 6 - diffusion in solids; 7 - notions of mechanics inside crystals; 8 - high temperature corrosion: phenomena, models, simulations; 9 - pseudo-stationary regime in heterogeneous kinetics; 10 - nucleation, growth and kinetic models; 11 - test experiments in heterogeneous kinetics; 12 - mechanical aspects of metal/oxide systems; 13 - coupling phenomena in high temperature oxidation; 14 - other corrosion types; 15 - methods of oxidized surfaces analysis at micro- and nano-scales; 16 - use of SIMS in the study of high temperature corrosion of metals and alloys; 17 - oxidation of ceramics and of ceramic matrix composite materials; 18 - protective coatings against corrosion and oxidation; 19 - high temperature corrosion in the 4. generation of nuclear reactor systems; 20 - heat exchangers corrosion in municipal waste energy valorization facilities; 21 - high temperature corrosion in oil refining and petrochemistry; 22 - high temperature corrosion in new energies industry. (J.S.)

  2. Corrosion study of bare and coated stainless steel

    Science.gov (United States)

    Morrison, J. D.

    1972-01-01

    A program was conducted at Kennedy Space Center from February 1968 to February 1971 to evaluate the performance of austenitic stainless steel alloys used in fluid systems lines. For several years, there had been numerous failures of stainless steel hardware caused by pitting and stress corrosion cracking. Several alloys were evaluated for effectiveness of certain sacrificial-type protective coverings in preventing corrosion failures. Samples were tested in specially designed racks placed 91 meters (100 yards) above high-tide line at Cape Kennedy. It is concluded that: (1) unprotected tubing samples showed evidence of pitting initiation after 2 weeks; (2) although some alloys develop larger pits than others, it is probable that the actual pitting rate is independent of alloy type; (3) the deepest pitting occurred in the sheltered part of the samples; and (4) zinc-rich coatings and an aluminum-filled coating have afforded sacrificial protection against pitting for at least 28 months. It is believed that a much longer effective coating life can be expected.

  3. Corrosion behavior of duplex polyaniline/epoxy coating on mild steel in 3% NaCl

    Directory of Open Access Journals (Sweden)

    Gvozdenovi? Milica M.

    2005-01-01

    Full Text Available The corrosion behavior and thermal stability of epoxy coatings electrodeposited on mild steel and on mild steel with electrochemically deposited polyaniline (PANI film were investigated by electrochemical impedance spectroscopy (EIS and thermo gravimetric analysis (TGA. The aim of the paper was to present new findings on the corrosion protection of mild steel by a duplex PANI/-epoxy coating in 3% NaCI solution and to determine the effect of thin PANI film on the protective properties of the coating. PANI film was deposited electrochemically on mild steel from an aqueous solution of 0.5 mol dm"3 sodium benzoate and 0.1 mol dm"3 aniline at a constant current density of 1.5 mA cm"2. Non-pigmented epoxy coatings on mild steel and on mild steel with PANI film were obtained by cathodic electrode position at constant voltage and stirring conditions. The resin concentration in the electrode position bath was 10 wt.% solid dispersion in water at pH 5.7. The applied voltage was 250 V, the temperature 26°C and the deposition time 3 min. It was shown that thin PANI film could be used to modify the surface of mild steel prior to epoxy coating deposition, due to the increased corrosion protection of a duplex PANI/epoxy coating comparing to an epoxy coating on mild steel in 3% NaCl solution.

  4. / Factorial design applied to corrosion of superduplex stainless steel

    Scientific Electronic Library Online (English)

    T.J., Mesquita; R.P., Nogueira; I.N., Bastos.

    2011-10-01

    Full Text Available [...] Abstract in english Steels employed in offshore oil and gas production are subject to a very corrosive environment. Especially the new oilfields located in pre-salt layers imply the contact of steels with high brine concentration, high temperature and presence of corrosive gas such as CO2. Besides these facts, stainles [...] s steels have to present higher mechanical properties obtained from an optimized heat treatment. In order to take into account these factors and their synergisms, on the present paper, we have chosen a factorial experimental design to study the corrosion behavior of superduplex steel UNS S32750 by electrochemical tests. The results of open circuit potential, polarization curves and electrochemical impedance were analyzed with statistical methods considering a confidence level of 95%. The factors that significantly affect the corrosion potential are the carbon dioxide and heat treatment; the corrosion current is sensitive to carbon dioxide, and the resistance of polarization is strongly affected by the CO2 content.

  5. Understanding corrosion via corrosion product characterization: II. Role of alloying elements in improving the corrosion resistance of Zn-Al-Mg coatings on steel

    International Nuclear Information System (INIS)

    Highlights: ? Origins of better corrosion resistance of ZnAlMg coatings than galvanized steel. ? Comparative study of corrosion products formed on ZnAlMg, ZnMg and Zn coatings. ? Modeling of dissolution and precipitation stages of corrosion. ? At early stages Mg stabilizes protective zinc basic salts during dry-wet cycling. ? At later stages Al dissolves at high pH forming protective layered double hydroxides. - Abstract: Corrosion products are identified on Zn, ZnMg and ZnAlMg coatings in cyclic corrosion tests with NaCl or Na2SO4 containing atmospheres. For Mg-containing alloys the improved corrosion resistance is achieved by stabilization of protective simonkolleite and zinc hydroxysulfate. At later stages, the formation of layered double hydroxides (LDH) is observed for ZnAlMg. According to thermodynamic modeling, Mg2+ ions bind the excess of carbonate or sulfate anions preventing the formation of soluble or less-protective products. A preferential dissolution of Zn and Mg at initial stages of corrosion is confirmed by in situ dissolution measurement. The physicochemical properties of different corrosion products are compared.

  6. Corrosion resistance of Cu-Ni-stainless steel multilayers for EMI shielding materials

    International Nuclear Information System (INIS)

    The metallic coatings for ElectroMagnetic Interference (EMI) shielding must have a low electric resistance for effective electromagnetic wave shielding as well as good corrosion resistance to guarantee reliability of the electronic devices. Normally, the metallic coating for EMI shielding consist of conductive layer, corrosion resistance layer and buffer layer. As the corrosion induced the delamination of coating layer, it could not function of EMI shielding. Therefore, in this paper, the effect of the stainless steel layer on the corrosion resistance was investigated. Several metals were deposited onto polycarbonate by RF magnetron sputtering. The structural characteristics of the film were investigated by means of X-Ray Diffractometry (XRD) and Scanning Electron Microscopy (SEM). The electrochemical properties were examined by potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS) in 3.5 wt.% NaCl solution. The results obtained from potentiodynamic polarization and EIS showed that 2205 stainless steel of upper layer had the better protective efficiency than 310S stainless steel

  7. Corrosion and wetting behaviour of metals and steels with molten alkali carbonates

    Science.gov (United States)

    Fisher, J. M.; Bennett, P. S.

    1991-02-01

    The corrosion and wetting behavior of metals and steels with molten alkali carbonates is of particular interest for the design of molten carbonate fuel cells. Such cells, operating at 650 C with a lithium and potassium carbonate electrolyte, offer a very corrosive medium for fuel cell components. Static corrosion tests under simulated anode conditions have shown that rhodium, ruthenium, platinum, palladium, silver, gold, Nickel 200 and Monel 400 exhibit no measurable corrosion over a 100 h period. Copper, Kanthal and Fecralloy exhibit good resistance with thin protective oxide layers. Stainless steels show less resistance to attack with thicker, more permeable oxide coatings being formed. In addition, contact angle measurements indicate that copper, gold, silver and ruthenium demonstrate appreciable nonwetting under a H2-CO2 atmosphere. Steels are substantially wetted.

  8. Polyelectrolyte-diffused zinc phosphate conversion coatings and polyacid coupling primers for corrosion protection of steel and aluminum, and alkali-catalyzed hydrolysis of polyimide-based materials: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Sugama, T.; Kukacka, L.E.; Carciello, N.R.; Warren, J.B.; Clayton, C.R.

    1989-08-01

    Under US Army Research Office (ARO) sponsorship, Brookhaven National Laboratory (BNL) performed research on three topics: (1) polyelectrolyte-modified zinc phosphate (Zn/center dot/Ph) conversion coatings for the corrosion protection of steel, (2) water-soluble polyacid coupling primers for improving the corrosion resistance and adherence of polymeric paints, and (3) high-temperature lightweight polyimide material systems. In the first topic, it was found that insoluble crystalline zinc phosphate (Zn/center dot/Ph) conversion coatings can be produced on steel surfaces by immersing a surface-cleaned cold-rolled steel substrate into a BNL-developed phosphating solution containing three components, zinc orthophosphate dihydrate (Zn/sub 3/(PO/sub 4/)/sub 2/sup /minus////center dot/2H/sub 2/O), H/sub 3/PO/sub 4/, and water. The major phase in the conversion coating derived from this simple phosphating solution is the same zinc phosphate dihydrate as that used in the converting solution. Referring to the second topic, it was found that the poly(itaconic acid), p(IA), which contains two functional COOH groups located on the same backbone carbon, has potential for use as a water-soluble intermediate coupling primer for polymer adhesive/Al/sub 2/O/sub 3/ adherend joint systems. Emphasis in the third topic was placed on understanding the reaction processes and degradation mechanisms of PI polymers which occur at the interfaces between the PI and inorganic pigments in hydrothermal environments at /ge/150/degree/C.

  9. Inhibition properties of self-assembled corrosion inhibitor talloil diethylenetriamine imidazoline for mild steel corrosion in chloride solution saturated with carbon dioxide

    International Nuclear Information System (INIS)

    Highlights: •Corrosion inhibitor talloil diethylenetriamine imidazoline effectively protects mild steel from CO2 corrosion. •Quartz crystal microbalance measurements were used to the investigate kinetics of corrosion inhibitor adsorption. •Adsorption of talloil diethylenetriamine imidazoline can be described by Langmuir adsorption isotherm. -- Abstract: The inhibition effect of talloil diethylenetriamine imidazoline (TOFA/DETA imidazoline) on corrosion of mild steel in chloride solutions saturated with CO2 was investigated by weight loss measurements (WL) and atomic force microscopy (AFM). Adsorption mechanism and kinetics of self-assembled (TOFA/DETA imidazoline) monolayers formation on gold were studied using the quartz crystal microbalance measurements (QCM). WL and AFM results demonstrated that TOFA/DETA imidazoline can effectively protect mild steel surface from corrosion. QCM measurements shown that the adsorption of TOFA/DETA imidazoline onto gold follows Langmuir adsorption isotherm and further investigation of the adsorption process will be carried out on a corroding metal surface

  10. Influence of temperature on corrosion rate and porosity of corrosion products of carbon steel in anoxic bentonite environment

    Science.gov (United States)

    Stoulil, J.; Ka?ok, J.; Kou?il, M.; Parschová, H.; Novák, P.

    2013-11-01

    The study focuses on the porosity of layers of corrosion products and its impact on corrosion rate of carbon steel in moist bentonite. Measurements were performed in an aggressive Czech type of bentonite - Rokle B75 at temperatures of 90 and 40 °C. Aggressiveness of B75 bentonite consists in low content of chlorides. Presence of chlorides in pore solution allows formation of more protective magnetite. The evaluation was made by electrochemical techniques (red/ox potential, open circuit potential, linear polarization resistance, impedance spectroscopy) and resistometric sensor measurements. The result imply that the higher the temperature the more compact is the layer of corrosion products that slightly decelerates corrosion rate compared to the state at 40 °C. The state of corrosion products at both temperatures is reversible.

  11. Corrosion of ODS steels in lead-bismuth eutectic

    International Nuclear Information System (INIS)

    Oxide dispersion strengthened (ODS) ferritic steels are advanced materials being developed for high temperature applications. Their properties (high temperature strength, creep resistance, corrosion/oxidation resistance) make them potentially usable for high temperature applications in liquid metal cooled systems like liquid lead-bismuth eutectic cooled reactors and spallation sources. Corrosion tests on five different ODS alloys were performed in flowing liquid lead-bismuth eutectic in the DELTA Loop at the Los Alamos National Laboratory at 535 deg. C for 200 h and 600 h. The tested materials were chromium alloyed ferritic/martensitic steels (12YWT, 14YWT, MA957) and Cr-Al alloyed steels (PM2000, MA956). It was shown that the Al alloyed ODS steel above 5.5 wt% Al (PM2000) is highly resistant to corrosion and oxidation in the conditions examined, and that the corrosion properties of the ODS steels depend strongly on their grain size

  12. Corrosion of ODS steels in lead bismuth eutectic

    Science.gov (United States)

    Hosemann, P.; Thau, H. T.; Johnson, A. L.; Maloy, S. A.; Li, N.

    2008-02-01

    Oxide dispersion strengthened (ODS) ferritic steels are advanced materials being developed for high temperature applications. Their properties (high temperature strength, creep resistance, corrosion/oxidation resistance) make them potentially usable for high temperature applications in liquid metal cooled systems like liquid lead-bismuth eutectic cooled reactors and spallation sources. Corrosion tests on five different ODS alloys were performed in flowing liquid lead-bismuth eutectic in the DELTA Loop at the Los Alamos National Laboratory at 535 °C for 200 h and 600 h. The tested materials were chromium alloyed ferritic/martensitic steels (12YWT, 14YWT, MA957) and Cr-Al alloyed steels (PM2000, MA956). It was shown that the Al alloyed ODS steel above 5.5 wt% Al (PM2000) is highly resistant to corrosion and oxidation in the conditions examined, and that the corrosion properties of the ODS steels depend strongly on their grain size.

  13. Corrosion of ODS steels in lead-bismuth eutectic

    Energy Technology Data Exchange (ETDEWEB)

    Hosemann, P. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Montanuniversitaet Leoben (Austria)], E-mail: peterh@lanl.gov; Thau, H.T.; Johnson, A.L. [University of Nevada Las Vegas (United States); Maloy, S.A.; Li, N. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States)

    2008-02-15

    Oxide dispersion strengthened (ODS) ferritic steels are advanced materials being developed for high temperature applications. Their properties (high temperature strength, creep resistance, corrosion/oxidation resistance) make them potentially usable for high temperature applications in liquid metal cooled systems like liquid lead-bismuth eutectic cooled reactors and spallation sources. Corrosion tests on five different ODS alloys were performed in flowing liquid lead-bismuth eutectic in the DELTA Loop at the Los Alamos National Laboratory at 535 deg. C for 200 h and 600 h. The tested materials were chromium alloyed ferritic/martensitic steels (12YWT, 14YWT, MA957) and Cr-Al alloyed steels (PM2000, MA956). It was shown that the Al alloyed ODS steel above 5.5 wt% Al (PM2000) is highly resistant to corrosion and oxidation in the conditions examined, and that the corrosion properties of the ODS steels depend strongly on their grain size.

  14. Corrosion fatigue in nitrocarburized quenched and tempered steels

    Science.gov (United States)

    Khani, M. Karim; Dengel, D.

    1996-05-01

    In order to investigate the fatigue strength and fracture mechanism of salt bath nitrocarburized steels, specimens of the steels SAE 4135 and SAE 4140, in a quenched and tempered state, and additionally in a salt bath nitrocarburized and oxidizing cooled state as well as in a polished (after the oxidizing cooling) and renewed oxidized state, were subjected to comparative rotating bending fatigue tests in inert oil and 5 pct NaCl solution. In addition, some of the quenched and tempered specimens of SAE 4135 material were provided with an approximately 50-?m-thick electroless Ni-P layer, in order to compare corrosion fatigue behavior between the Ni-P layer and the nitride layers. Long-life corrosion fatigue tests of SAE 4135 material were carried out under small stresses in the long-life range up to 108 cycles with a test frequency of 100 Hz. Fatigue tests of SAE 4140 material were carried out in the range of finite life (low-cycle range) with a test frequency of 13 Hz. The results show that the 5 pct NaCl environment drastically reduced fatigue life, but nitrocarburizing plus oxidation treatment was found to improve the corrosion fatigue life over that of untreated and Ni-P coated specimens. The beneficial effect of nitrocarburizing followed by oxidation treatment on cor-rosion fatigue life results from the protection rendered by the compound layer by means of a well-sealed oxide layer, whereby the pores present in the compound layer fill up with oxides. The role of inclusions in initiating fatigue cracks was investigated. It was found that under corrosion fatigue conditions, the fatigue cracks started at cavities along the interfaces of MnS inclusions and matrix in the case of quenched and tempered specimens. The nitrocarburized specimens, however, showed a superposition of pitting corrosion and corrosion fatigue in which pores and nonmetallic inclusions in the compound layer play a predominant role concerning the formation of pits in the substrate.

  15. Corrosion Inhibition and Adsorption of Anthocleista Djalonesis Leaf Extract on the Acid Corrosion of Mild Steel

    OpenAIRE

    C.E. Ogukwe; C.O. Akalezi; M. A. Chidiebere; K.L. Oguzie; Z.O. Iheabunike; E.E. Oguziea

    2012-01-01

    Aqueous extracts of the leaves of Anthocleista djalonesis (AD) have been investigated as non toxic corrosion inhibitors for mild steel in acidic environments (1 M HCl and 0.5 M H2SO4, respectively). Corrosion rates were evaluated at 30 °C using the weight loss, electrochemical impedance spectroscopy and potentiodynamic polarization techniques. AD extract was found to inhibit mild steel corrosion in both acidic media via adsorption of the extract organic matter on the metal/solution interface....

  16. Corrosion resistant structural materials and protective metal coatings for power engineering

    International Nuclear Information System (INIS)

    Corrosion resistant materials used for manufacturing NPP heat exchanger systems and heat resistant protective coatings are considered. Noted is development and application of a number of steels (EhP350, EhP 756, EhP 882), intended to substitute the 08Kh18N10T steel and having higher resistance to corrosion cracking, to intercrystalline and pitting corrosion at temperatures up to 350 deg C at a smaller Ni content. Considered is the problem of improvement of chemical deposition of Ni-based alloys (Ni-P, Ni-P-W, Ni-B) for protection of the NPP components

  17. Corrosion and Stress Corrosion Behaviors of Low and Medium Carbon Steels in Agro-Fluid Media

    Directory of Open Access Journals (Sweden)

    Ayo Samuel AFOLABI

    2007-01-01

    Full Text Available Investigations were carried out to study critically the corrosion behaviour and Stress Corrosion Cracking (SCC of low and medium carbon steels in cassava and cocoa extracts by weight loss measurement and constant extension to fracture method respectively. The results obtained showed that medium carbon steel is more susceptible to corrosion than low carbon steel in both media. SCC is also more in medium carbon steel than low carbon steel in the two media under study. These deductions are due to higher carbon content in medium carbon steel coupled with various aggressive corrosion constituents contained in these media. Hydrogen embrittlement, as well as carbon cracking, is responsible for SCC of these materials in the agro-fluid media.

  18. In situ 3D monitoring of corrosion on carbon steel and ferritic stainless steel embedded in cement paste

    International Nuclear Information System (INIS)

    Highlights: • The morphology of the corrosion of steel in cement paste was studied in situ. • During galvanostatic corrosion, carbon steel reinforcement corroded homogeneously. • On ferritic stainless steel, deep corrosion pits formed and caused wider cracks. • The measured rate of steel loss correlated well with Faraday’s law of electrolysis. - Abstract: In a X-ray microcomputed tomography study, active corrosion was induced by galvanostatically corroding steel embedded in cement paste. The results give insight into corrosion product build up, crack formation, leaching of products into the cracks and voids, and differences in morphology of corrosion attack in the case of carbon steel or stainless steel reinforcement. Carbon steel was homogeneously etched away with a homogeneous layer of corrosion products forming at the steel/cement paste interface. For ferritic stainless steel, pits were forming, concentrating the corrosion products locally, which led to more extensive damage on the cement paste cover

  19. Electrochemical Studies of Stainless Steel Corrosion in Peroxide Solutions

    Directory of Open Access Journals (Sweden)

    Ajay K. Singh

    2012-03-01

    Full Text Available Pollution control measures have resulted in replacement of chlorine by peroxide as bleaching chemical. Change of chemical affects corrosion aspects, the suitability of existing plant metallurgy and materials of construction of bleach plants. Accordingly long term immersion and electrochemical corrosion tests were conducted on stainless steel 304L, 316L, 2205 and 6% Mo and mild steel in peroxide solutions of pH 10. The materials were tested for uniform corrosion, pitting and crevice corrosion and attack around the weld area. Corrosion attack estimated from long term immersion tests is found in agreement, by and large, with that analyzed from electrochemical test. E-pH diagrams drawn for water-peroxide system have been used to understand the corrosivity of the peroxide media. An attempt has been made to suggest a suitable material of construction for handling the test media on the basis of degree of corrosion attack on them and their cost and the mechanical properties.

  20. Experiences of corrosion and corrosion protection in seawater systems in the Nordic countries

    International Nuclear Information System (INIS)

    A summary is given of the experience of the corrosion resistance of pumps, heat exchangers, valves and pipings in different seawater cooling systems in Scandinavia, including power reactor cooling systems in Finland and Sweden. For pumps and heat exchangers the experience has been so extensive that a clear picture of today's standing can be given. Owing to scanty data concerning valves and pipes, the survey of the corrosion in these components is less well supported. Vertically extended centrifugal pumps are the pumps in general use in power plant cooling systems. To counteract corrosion on pump riser and pump casing having an organic surface coating, and on stainless steel shafts and impellers, these components should be provided with internal and external cathodic protection. For tube and plate type heat exchangers, titanium has proved to be the best material choice. Rubber-enclosed carbon steel pipings, or pipings having a thick coating of epoxy plastic, have shown very strong corrosion resistance in power plant seawater cooling systems. Valves in seawater systems have primarily been affected by corrosion due to poorly executed or damaged organic coating on cast iron. Different seawater-resistant bronzes (red bronze, tin bronze and aluminium bronze) are therefore preferable as valve materials

  1. Atmospheric corrosion of mild steel. Pt. II. Marine atmospheres

    International Nuclear Information System (INIS)

    This paper summarizes the results obtained in the MICAT project for mild steel specimens exposed for 1 to 4 years in 47 marine atmospheres in the Ibero-American region. All these atmospheres were characterized for climatology, pollution and corrosion rates according to ISO standards. Complementary morphological and chemical characterization of the steel corrosion product layers (SCPLs) formed in these atmospheres was carried out. The overall analysis of results contributes to understanding, in a systematic way, how atmospheric corrosivity categories can be correlated with corrosion mechanisms. Special aspects of the atmospheres, from pure to mixed marine, were considered. (orig.)

  2. The role of molybdenum in corrosion resistance of stainless steel

    International Nuclear Information System (INIS)

    The effect of Mo on corrosion properties of stainless steels in 1M MgCl2 solution was studied using an electrochemical polarization method. Procedure for the preparation of electrochemically polarized samples for surface analysis is described. The samples surface were analyzed using X-ray Photoelectron Spectroscopy (XPS). The stainless steel which has high Mo content has a better resistance to corrosion in Cl containing media. Cr and Mo are enriched in the surface of Mo-bearing stainless steels which have undergone high anodic-metal dissolution. Mo may exist as MoO2 which is responsible in slowing down the rate of corrosion attack. (author)

  3. Model for microbiologically influenced corrosion of carbon steels

    International Nuclear Information System (INIS)

    Over the past 5 years, extensive chemical, metallurgical, and biological information has been collected from corrosion sites from many different components composed of carbon steel, stainless steels, and copper alloys exposed to a variety of environments. The purpose of this extensive sampling was to determine those conditions under which microbiologically influenced corrosion (MIC) of various alloys occur and to describe the physical, biological, and chemical characteristics in the corrosion sites that would most likely indicate MIC. This paper concentrates on a model of MIC in carbon steels because the most complete information is available for this case

  4. Electrochemical study of the crevice corrosion resistance of stainless steels: example of Cr-Mo ferritic steels

    International Nuclear Information System (INIS)

    The measurement of stainless steel depassivating pH enables the crevice corrosion resistance to be evaluated. It is concluded that: Mo is more efficient than Cr; the classification of the stainless steel types is not the same for pitting and crevice corrosion resistance; crevice corrosion resistance of Cr-Mo ferritic steels is similar to that of Cr-Ni-Mo austenitic steels

  5. Prediction of external corrosion for steel cylinders

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) currently manages the UF6 Cylinder Program (the program). The program was formed to address the depleted-uranium hexafluoride (UF6) stored in approximately 50,000 carbon steel cylinders. The cylinders are located at three DOE sites: the K-25 site (K-25) at Oak Ridge, Tennessee; the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The System Requirements Document (SRD) (LMES 1996a) delineates the requirements of the program. The appropriate actions needed to fulfill these requirements are then specified within the System Engineering Management Plan (SEMP) (LMES 1996b). The report presented herein documents activities that in whole or in part satisfy specific requirements and actions stated in the UF6 Cylinder Program SRD and SEMP with respect to forecasting cylinder conditions. The wall thickness projections made in this report are based on the assumption that the corrosion trends noted will continue. Some activities planned may substantially reduce the rate of corrosion, in which case the results presented here are conservative. The results presented here are intended to supersede those presented previously, as the quality of several of the datasets has improved

  6. Corrosion of reinforcement bars in steel ibre reinforced concrete structures

    DEFF Research Database (Denmark)

    Solgaard, Anders Ole Stubbe

    2014-01-01

    Steel fibres have been known as an alternative to traditional reinforcement bars for special applications of structural concrete for decades and the use of steel fibre reinforced concrete (SFRC) has gradually increased in recent years. Steel fibres lead to reduced crack widths in concrete formed, among other reasons, due to shrinkage and/or mechanical loading. Steel fibres are nowadays also used in combination with traditional reinforcement for structural concrete, where the role of the fibres is to minimize the crack widths whereas the traditional reinforcement bars are used for structural purpose. Although such, so-called, combined reinforcement systems, are gaining impact within the construction industry, they are only marginally covered by existing guidelines for structural design and the literature concerning their mechanical and, in particular their durability aspects, is sparse. The aim of the work presented in this Ph.D. thesis was to quantify the influence of steel fibres on corrosion of traditionalreinforcement bars embedded in uncracked concrete as well as cracked concrete. Focus of the work was set on the impact of steel fibres on corrosion propagation in uncracked concrete and the influence of steel fibres on initiation and propagation of cracks in concrete. Moreover, the impact of fibres on corrosion-induced cover cracking was covered. The impact of steel fibres on propagation of reinforcement corrosion was investigated through studies of their impact on the electrical resistivity of concrete, which is known to affect the corrosion process of embedded reinforcement. The work concerning the impact of steel fibres on initiation and propagation of cracks was linked to corrosion initiation and propagation of embedded reinforcement bars via additional studies. Cracks in the concrete cover are known to alter the ingress rate of depassivating substances and thereby influence the corrosion process. The Ph.D. study covered numerical as well as experimental studies. Electrochemically passive steel fibres are electrically isolating thus not changing the electrical resistivity of concrete, whereas electrochemically active (depassivated/corroding) steel fibres are conducting. The impact of electrochemically active (depassivated/corroding) steel fibres on the electrical resistivity of SFRC was studied experimentally and analytically herein. Those studies showed that the addition of electrically conductive steel fibres may potentially reduce the electrical resistivity of concrete. Numerical studies of the correlation between the corrosion rate and the electrical resistivity of concrete were presented to study the impact of conductive steel fibres on the corrosion propagation phase of reinforcement bars. It was observed that under extreme conditions, viz. conductive (depassivated/corroding) steel fibres throughout the concrete volume, the reduction of the electrical resistivity caused by conductive fibres lead to a remarkable increase in the corrosion rate. However it is stressed that the case of corroding steel fibres throughout the concrete volume is somewhat hypothetical due to the very high corrosion-resistance of embedded steel fibres. Thus the investigated case refers to a worst-case scenario. Numerical and experimental studies on the impact of steel fibres on initiation and propagation of load-induced cracks in concrete showed that the steel fibres restrained the crack width of a bending crack through the concrete cover, once the crack was formed. Moreover the numerical studies showed that the length of separation at the concrete/steel-bar interface (displacement discontinuity perpendicular to the reinforcement bar) was reduced for SFRC compared to plain concrete, whereas there was no clear impact on the slip at the concrete/steel-bar (displacement discontinuity parallel to the reinforcement bar) caused by the steel fibres. Additional experimental and numerical studies concerning corrosion of reinforcement embedded in cracked concrete (plain concrete and SFRC) showed that the time-to-corrosion-intiation was similar

  7. Effect of environment on corrosion characteristics of newly developed DMR-1700 structural steel

    Directory of Open Access Journals (Sweden)

    Injeti Gurrappa and Guntupalli Malakondaiah

    2008-01-01

    Full Text Available The corrosion resistance of any metallic material depends on the environment to which it is exposed. DMR-1700 steel is a material for structural applications that has been recently developed at Defence Metallurgical Research Laboratory by changing the chemistry of alloying elements. Therefore, a detailed understanding of its corrosion characteristics under different environmental conditions is essential. In the present paper, we report the results of a systematic corrosion study that was carried out on the new steel to determine the effect of the environment on the protective nature of the oxide scale that forms on its surface under different environmental conditions. Furthermore, the oxide scale as well as the resistance to pitting and crevice corrosion were studied in various environments. The surface morphologies of the corroded steels were observed under a scanning electron microscope (SEM to determine the nature of the corrosion. On the basis of studies by different techniques, DMR-1700 steel is recommended for the manufacture of components used in various systems in conjunction with the application of an appropriate protective coating to improve its resistivity to corrosion.

  8. Effect of environment on corrosion characteristics of newly developed DMR-1700 structural steel

    Science.gov (United States)

    Gurrappa, Injeti; Malakondaiah, Guntupalli

    2008-04-01

    The corrosion resistance of any metallic material depends on the environment to which it is exposed. DMR-1700 steel is a material for structural applications that has been recently developed at Defence Metallurgical Research Laboratory by changing the chemistry of alloying elements. Therefore, a detailed understanding of its corrosion characteristics under different environmental conditions is essential. In the present paper, we report the results of a systematic corrosion study that was carried out on the new steel to determine the effect of the environment on the protective nature of the oxide scale that forms on its surface under different environmental conditions. Furthermore, the oxide scale as well as the resistance to pitting and crevice corrosion were studied in various environments. The surface morphologies of the corroded steels were observed under a scanning electron microscope (SEM) to determine the nature of the corrosion. On the basis of studies by different techniques, DMR-1700 steel is recommended for the manufacture of components used in various systems in conjunction with the application of an appropriate protective coating to improve its resistivity to corrosion.

  9. The effect of organic matter associated with the corrosion products on the corrosion of mild steel in the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Wagh, A.B.

    The corrosion of mild steel immersed at various depths (0-100 m) from three stations of the Arabian Sea was investigated. The corrosion of mild steel decreased with increasing immersion depth. Significant positive relationships were observed between...

  10. Role of nanophase oxides in short-term atmospheric corrosion of structural steels

    Science.gov (United States)

    Balasubramanian, Rama

    Systematic studies on the development of nanophase iron oxides in the corrosion products of carbon and weathering steel were performed to understand the role of nanophase oxides in short-term atmospheric corrosion. Similarities and/or differences between short-term and long-term atmospheric corrosion were established by studying carbon steel and weathering steel coupons exposed in mild marine environments for short-term and comparing it with previously established long-term data. Influence of substitutional elements, in particular chromium, in forming nanophase goethite was investigated. Crystallographic, magnetic and morphological properties of nanophase chromium substituted goethite have been characterized in order to understand the protective nature of chromium-substituted goethite in a naturally weathered steel surface. Spectroscopic investigation of the corrosion products of both carbon and weathering steel indicated that lepidocrocite and goethite were the predominant oxides to form following short-term exposures. The corrosion coatings were well layered for exposure times as early as 2 months. The layering was very similar to that observed on steel coupons exposed for more than 8 years. The outer layer was composed of lepidocrocite and occasionally goethite. The inner layer was mainly composed of nanophase goethite. The relative fraction of nanophase goethite was significantly higher in weathering steel compared to carbon steel at the end of six months of exposure. The data analysis also revealed that during the first two months of exposure weathering steel corrodes faster than carbon steel. However carbon steel corrodes more rapidly after 6 months of exposure. At the end of one year, the corrosion rate of carbon steel is higher than weathering steel. It is proposed that during the couple of months, nucleation of oxides is the dominant process in both carbon and weathering steel. At the end of six months, a considerable amount of nanophase goethite formed on carbon steel continues to grow into bigger crystals. On the other hand, in weathering steel the crystal growth of a significant fraction of initially formed nanophase goethite is inhibited. It is proposed that substitutional elements like chromium inhibit the crystal growth in weathering steel. The crystallographic and spectroscopic data for showed that with increasing chromium concentration, the crystallite size of synthetic goethite measured from X-ray diffraction and particle length of goethite measured from Mossbauer spectroscopy and Transmission Electron Microscopy, became smaller. (Abstract shortened by UMI.)

  11. Cathodic protection of steel pipes and its modeling

    International Nuclear Information System (INIS)

    Cathodic protection is a technique of reducing the corrosion rate of buried or immersed metallic structure by making the steady state or corrosion electrical potential of the metal sufficiently more electronegative. Experiments have been conducted with steel pipes lm in length immersed in various electrolytes and subjected to impressed cathodic protection. Potentials at different points within the length of the pipe were measured by standard electrodes. The potential distribution within the pipeline depend on impressed current applied, resistivity of electrolyte, resistance of coating and presence of coatings

  12. Corrosion-resistant Foamed Cements for Carbon Steels

    Energy Technology Data Exchange (ETDEWEB)

    Sugama T.; Gill, S.; Pyatina, T., Muraca, A.; Keese, R.; Khan, A.; Bour, D.

    2012-12-01

    The cementitious material consisting of Secar #80, Class F fly ash, and sodium silicate designed as an alternative thermal-shock resistant cement for the Enhanced Geothermal System (EGS) wells was treated with cocamidopropyl dimethylamine oxide-based compound as foaming agent (FA) to prepare numerous air bubble-dispersed low density cement slurries of and #61603;1.3 g/cm3. Then, the foamed slurry was modified with acrylic emulsion (AE) as corrosion inhibitor. We detailed the positive effects of the acrylic polymer (AP) in this emulsion on the five different properties of the foamed cement: 1) The hydrothermal stability of the AP in 200 and #61616;C-autoclaved cements; 2) the hydrolysis-hydration reactions of the slurry at 85 and #61616;C; 3) the composition of crystalline phases assembled and the microstructure developed in autoclaved cements; 4) the mechanical behaviors of the autoclaved cements; and, 5) the corrosion mitigation of carbon steel (CS) by the polymer. For the first property, the hydrothermal-catalyzed acid-base interactions between the AP and cement resulted in Ca-or Na-complexed carboxylate derivatives, which led to the improvement of thermal stability of the AP. This interaction also stimulated the cement hydration reactions, enhancing the total heat evolved during cement’s curing. Addition of AP did not alter any of the crystalline phase compositions responsible for the strength of the cement. Furthermore, the AP-modified cement developed the porous microstructure with numerous defect-free cavities of disconnected voids. These effects together contributed to the improvement of compressive-strength and –toughness of the cured cement. AP modification of the cement also offered an improved protection of CS against brine-caused corrosion. There were three major factors governing the corrosion protection: 1) Reducing the extents of infiltration and transportation of corrosive electrolytes through the cement layer deposited on the underlying CS surfaces; 2) inhibiting the cathodic reactions at the corrosion site of CS; 3) extending the coverage of cement over CS surfaces; and, 4) improving the adherence of the cement to CS surfaces. Thus, the CS’s corrosion rate of 176 milli inch/per year (mpy) for 1 wt% FA-foamed cement without AP was considerably reduced to 69 mpy by adding only 2 wt% AP. Addition of AP at 10 wt% further reduced this rate to less than 10 mpy.

  13. Corrosion Behaviour of Nickel Plated Low Carbon Steel in Tomato Fluid

    Directory of Open Access Journals (Sweden)

    Oluleke OLUWOLE

    2010-12-01

    Full Text Available This research work investigated the corrosion resistance of nickel plated low carbon steel in tomato fluid. It simulated the effect of continuous use of the material in a tomato environment where corrosion products are left in place. Low carbon steel samples were nickel electroplated at 4V for 20, 25, 30 and 35 mins using Watts solution.The plated samples were then subjected to tomato fluid environment for for 30 days. The electrode potentials mV (SCE were measured every day. Weight loss was determined at intervals of 5 days for the duration of the exposure period. The result showed corrosion attack on the nickel- plated steel, the severity decreasing with the increasing weight of nickel coating on substrate. The result showed that thinly plated low carbon steel generally did not have any advantage over unplated steel. The pH of the tomato solution which initially was acidic was observed to progress to neutrality after 4 days and then became alkaline at the end of the thirty days test (because of corrosion product contamination of the tomatocontributing to the reduced corrosion rates in the plated samples after 10 days. Un-plated steel was found to be unsuitable for the fabrication of tomato processing machinery without some form of surface treatment - thick nickel plating is suitable as a protective coating in this environment.

  14. Measuring system for enhanced cathodic corrosion protection

    OpenAIRE

    Angelini, Emma Paola Maria Virginia; Grassini, Sabrina; Parvis, Marco; Ferraris, Franco

    2012-01-01

    Buried metallic artifacts in soil or seawater are exposed to high risk of corrosion due to the contact with the surrounding aggressive environment. The protection of a wide range of iron-based artifacts is carried out by means of cathodic protection (CP)systems. CP is a technique used to control the corrosion of a metal surface by making it the cathode of an electrochemical cell, through the connection of the metal to be protected with another more easily corroded "sacrificial metal" acting a...

  15. 49 CFR 192.461 - External corrosion control: Protective coating.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Protective coating... for Corrosion Control § 192.461 External corrosion control: Protective coating. (a) Each external protective coating, whether conductive or insulating, applied for the purpose of external corrosion...

  16. Effects of cathodic protection on corrosion fatigue

    International Nuclear Information System (INIS)

    The effects of cathodic protection on corrosion fatigue of alloys can vary widely, ranging from strongly beneficial to strongly detrimental. This paper provides a concise synopsis of the subject, based upon a review of selected literature. Attempts are made to discern important generalizations concerning the effects of various cathodic protection levels on crack initiation and crack propagation in ferrous and nonferrous alloy systems

  17. AFM study of steel corrosion in aqueous solutions in concrete

    Directory of Open Access Journals (Sweden)

    Díaz-Benito, B.

    2011-03-01

    Full Text Available Early corrosion stages are studied in carbon steel by means of a solution simulating that contained in concrete pores. Non-carbonated solution contains 5% NaCl. The atomic force microscopy (AFM technique is used to study material performance after different immersion times (up to 48 h. Obtained data are compared to electrochemical ones (corrosion potential and polarization resistance. Analysis of images and roughness evolution along time shows that steel initially tends to reach passivity, although the passive layer rapidly loses its protective character due to chloride attack.

    Este trabajo estudia los primeros estados de la corrosión de un acero al carbono en una disolución que simula la existente en los poros del hormigón, sin carbonatar, con un 5% de NaCl. Para ello, se ha empleado la técnica de microscopía de fuerza atómica (AFM, estudiando el comportamiento del material tras diferentes tiempos de inmersión, hasta 48 h, en la disolución. Estos datos se comparan con datos electroquímicos (potencial de corrosión y resistencia de polarización. El análisis de las imágenes y la evolución de la rugosidad con el tiempo muestran que el acero tiende inicialmente a pasivarse, pero la capa pasiva pierde rápidamente su carácter protector debido al ataque de los cloruros.

  18. Investigation for anti-stress corrosion cracking of SUS 304 stainless steel weldments

    International Nuclear Information System (INIS)

    The anti-stress corrosion cracking method by current density of cathodic protection was studied for stress corrosion cracking of SUS 304 stainless steel weldments in the environment of various MgCl2 boiling solution (wt%). Main results obtained are as follows: 1) Under the conditions below the critical current density of cathodic protection for anti-stress corrosion cracking, the latent time of crack initiation of weld heat affected zone occurs more rapidly than that of base metal because of the phenomenon of sensitizing and softening caused by weld heat cycles. 2) Under the constant current density of cathodic protection, the anti-stress corrosion cracking of weld heat affected zone can be controlled by critical concentration of MgCl2 solution. 3) The critical current density of cathodic protection of weld heat affected zone increases in proportion to concentration of MgCl2 solution. (Author)

  19. Corrosion behavior of carbon steels under tuff repository environmental conditions

    International Nuclear Information System (INIS)

    Carbon steels may be used for borehole liners in a potential high-level nuclear waste repository in tuff in Nevada. Borehole liners are needed to facilitate emplacement of the waste packages and to facilitate retrieval of the packages, if required. Corrosion rates of low carbon structural steels AISI 1020 and ASTM A-36 were determined in J-13 well water and in saturated steam at 1000C. Tests were conducted in air-sparged J-13 water to attain more oxidizing conditions representative of irradiated aqueous environments. A limited number of irradiation corrosion and stress corrosion tests were performed. Chromium-molybdenum alloy steels and cast irons were also tested. These materials showed lower general corrosion but were susceptible to stress corrosion cracking when welded. 4 references, 4 tables

  20. Corrosion behavior of carbon steels under tuff repository environmental conditions

    International Nuclear Information System (INIS)

    Carbon steels may be used for borehole liners in a potential high-level nuclear waste repository in tuff in Nevada. Borehole liners are needed to facilitate emplacement of the waste packages and to facilitate retrieval of the packages, if required. Corrosion rates of low carbon structural steels AISI 1020 and ASTM A-36 were determined in J-13 well water and in saturated steam at 1000C. J-13 well water is representative of water which has percolated through the tuff horizon where the repository would be located. Tests were conducted in air-sparged J-13 water to attain stronger oxidizing conditions. a limited number of irradiation corrosion and stress corrosion tests were performed. Chromium-molybdenum alloy steels and cast irons were also tested. These materials showed lower general corrosion but were susceptible to stress corrosion cracking when welded. 4 refs., 7 tabs

  1. Corrosion of Steel in Concrete – Thermodynamical Aspects

    DEFF Research Database (Denmark)

    Küter, Andre; Møller, Per; Geiker, Mette Rica

    2004-01-01

    The present understanding of selected corrosion phenomena in reinforced concrete is reviewed. Special emphasis is given to chloride induced corrosion. There is a general acceptance of the basic corrosion mechanism for steel in concrete. However different anodic reactions governing the subsequent...... formation and composition of corrosion products have been proposed. Suggested reactions, except half-cell reactions, are verified or rejected based on their Gibbs free energy, while the electrode potential is calculated for half-cell reactions. Corrosion products postulated to form are related to...

  2. Corrosion Behavior of Mild Carbon Steel in Ethanolic Solutions

    Science.gov (United States)

    Bhola, Shaily M.; Bhola, Rahul; Jain, Luke; Mishra, Brajendra; Olson, David L.

    2011-04-01

    Electrochemical evaluation of ASTM A36 steel was performed in ethanolic solutions containing small concentrations of water ranging from 0 to 10 vol.%. Electrochemical techniques such as open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization were utilized to analyze corrosion parameters. A fixed concentration of chloride, as per the ASTM specification for fuel grade ethanol, was added to increase the conductivity of the solutions. The effects of water and oxygen on the corrosion behavior of steel in these solutions have been discussed. Pitting corrosion of the steel specimens in these solutions was evaluated using scanning electron microscopy (SEM) and pitting analysis. This investigation was performed to establish a baseline for the microbiologically influenced corrosion (MIC) of steel in ethanolic solutions.

  3. Corrosion resistance of chromium-nickel steel containing rare earths

    International Nuclear Information System (INIS)

    Effect of additional out-of-furnace treatment with complex alloy (foundry alloy) calcite-silicon-magnesium-rare earth metal on corrosion resistance of the 03Kh18N20M3D3C3B steel has been studied. It is shown that introduction of low additions of rare earths improves its corrosion resistance improves its corrosion resistance in agressive media (in 70% - sulfuric acid) in the range of transition from active to passive state. Effect of additional introduction of rare earth metals is not considerable, if potential of steel corrosion is in the range of stable passive state (32% - sulfuric acid). Additional out-of-furnace treatment with complex foundry alloy, containing rare earth metals, provides a possibility to use a steel with a lower content of Cr, Ni, Mo, than in conventional acid-resistant steels in highly agressive media

  4. Corrosion resistance of high-manganese austenitic steels

    Directory of Open Access Journals (Sweden)

    A. Grajcar

    2010-02-01

    Full Text Available Purpose: The aim of the paper is to compare the corrosion resistance of two new-developed high-manganese austenitic steels in 1N H2SO4 and 3.5% NaCl solutions.Design/methodology/approach: The steels used for the investigation were thermo-mechanically rolled and then solution heat-treated from a temperature of 850°C. Corrosion resistance of investigated steels was examined using the immersion test. The specimens were weighed and dipped in the prepared solutions for 100 h. After the test, the percentage weight loss was calculated. The metallographic investigations of corrosion damages included light and scanning electron microscope observations both in the polished and etched states.Findings: It was found that after the thermo-mechanical processing one steel is characterized by an austenitic structure with numerous annealing twins, whereas in the second steel ? and ?’ martensite plates in an austenitic matrix were observed. According to the results of the immersion tests it was found that the examined steels exhibit a comparable corrosion resistance. They show very poor corrosion resistance in H2SO4 solution and low corrosion resistance in NaCl medium. The weight loss in chloride solution is much lower, what is explained by different corrosion mechanisms. In both the solutions, the intensive general corrosion and corrosion pitting were observed. In acidic medium they are created in a way of hydrogen depolarization and in NaCl in the way of oxygen depolarization.Research limitations/implications: To investigate in more detail the corrosion behaviour of high-manganese austenitic steels, the investigations should include polarization tests and an analysis of corrosion products.Practical implications: The obtained results can be used to search for the appropriate way of improving the corrosion resistance of high-manganese steels with a single-phase austenitic structure as well as the austenite structure containing ? and ?’ martensite.Originality/value: The corrosion resistance of two types of advanced high-strength high-manganese austenitic steels with different initial structures was compared in acidic and chloride solutions.

  5. Corrosion of alloy steels in oil field fluids

    International Nuclear Information System (INIS)

    Laboratory and field tests have been conducted on two low alloy and two higher alloy steels at a range of brine salinities and sulfide contents typical of oil well production fluids. AISI types 4130 and 4340 show the same behavior in these fluids as mild steel. AISI type 410 stainless steel and 9% chromium - 1% molybdenum steel corrode at rates as great as that of mild steel at higher chloride or sulfide concentrations. Special corrosion inhibitors are required for higher alloy steels when they are exposed to these conditions

  6. Effect of Geobacter sulfurreducens on the microbial corrosion of mild steel, ferritic and austenitic stainless steels

    International Nuclear Information System (INIS)

    The influence of Geobacter sulfurreducens was tested on the anaerobic corrosion of four different steels: mild steel 1145, ferritic steel 403 and austenitic steels 304L and 316L. Within a few hours, the presence of cells induced a free potential (Eoc) ennoblement around +0.3 V on 1145 mild steel, 403 ferritic steel and 304L austenitic steels and slightly less on 316L. The kinetics of Eoc ennoblement depended on the amount of bacteria in the inoculum, but the final potential value depended essentially on the nature of the material. This effect was due to the capacity of G. sulfurreducens to create a direct cathodic reaction on steel surfaces, extracting the electrons directly from material. The presence of bacterial cells modified the corrosion features of mild steel and ferritic steel, so that corrosion attacks were gathered in determined zones of the surface. Local corrosion was significantly enhanced on ferritic steel. Potential ennoblement was not sufficient to induce corrosion on austenitic steels. In contrast G. sulfurreducens delayed the occurrence of pitting on 304L steel because of its capability to oxidize acetate at high potential values. The electrochemical behaviour of 304L steel was not affected by the concentration of soluble electron donor (acetate, 1-10 mM) or the amount of planktonic cells; it was directly linked to the biofilm coverage. After polarization pitting curves had been recorded, microscopic observations showed that pits propagated only in the surface zones where cell settlement was the densest. The study evidenced that Geobacter sulfurreducens can control the electrochemical behaviour of steels in complex ways that can lead to severe corrosion. As Geobacteraceae are ubiquitous species in sediments and soils they should now be considered as possible crucial actors in the microbial corrosion of buried equipment.

  7. Corrosion resistance of some stainless steels in titanium tetrachloride

    International Nuclear Information System (INIS)

    In this paper, the corrosion behavior of the W 4306, W 4541 and W 4571 stainless steels in anhydrous TiCl4, TiCl4 with 1 o/oo vol. H2O and TiCl4 with 1% vol. H2O addition at ambient temperature, in liquid-vapor phases and phase separation limit is studied. The corrosion rate (mm/year), pitting susceptibility and stress corrosion cracking susceptibility (45 kgf/mm2 applied stress) as well as the corrosion effects on the mechanical properties are determined. Our investigations led to the following results: all the three steel types studied are fairly stable in anhidrous TiCl4 atmosphere, while in vapor phase the corrosion rate is lower than that in liquid phase; addition of 1 o/oo vol. H2O induces no changes in the corrosion resistance of W 4306 and W 4571 type steels, but does affect the W 4541 type steel which in liquid phase undergoes pitting attack; addition of 1% vol. H2O induces changes in the corrosion resistance of W 4571 type steel, with no change concerning the type of corrosion attack; no corrosion enhancement at the liquid/vapor phase interface was observed, independently of the hydration degree of TiCl4; all the steel samples investigated showed endurance to cracking corrosion under up to 45 kgf/mm2 testing stress, independently of the testing conditions; mechanical characteristics did not changed in anhydrous TiCl4 and TiCl4 with 1% vol.H2O addition, both in liquid and vapor phases. (authors)

  8. Corrosion behaviour and galvanic coupling with steel of Al-based coating alternatives to electroplated cadmium

    International Nuclear Information System (INIS)

    The galvanic corrosion behaviour of bare steel coupled to steel with an Al–Zn flake inorganic spin coating, an Al-based slurry sprayed coating, an arc sprayed Al coating and electroplated cadmium has been investigated. The sacrificial and galvanic behaviour of the coatings was studied in 3.5 wt. % NaCl solution using open-circuit potential, potentiodynamic polarisation and electrochemical noise measurements. The coatings were characterised by scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction. Experimental results showed that the Al-based slurry sprayed coating exhibited an open-circuit potential closer to the steel substrate than other coatings, as well as a low corrosion current density and a more positive corrosion potential. In terms of the galvanic suitability of the investigated coatings for the steel substrate, both the Al–Zn flake inorganic spin coating and the Al-based slurry sprayed coating show low galvanic current, in comparison with the arc sprayed Al coating and electroplated cadmium. This behaviour confirms their superior cathodic protection capability and galvanic compatibility over other coatings tested. Electrochemical noise measurements provide accurate information on the coatings' galvanic behaviour, which can be complimented by the data obtained from superposition of potentiodynamic corrosion scans of the coating and bare steel, provided that the corrosion potential difference between the two materials does not exceed 300 mV. - Highlights: • Al-based slurry coating has best galvanic compatibility with steel. • Mg, Cr, P in Al-based slurry coating reinforce its corrosion resistance. • Ennoblement of Al–Zn flake coating compromises its cathodic protection. • Poor corrosion behaviour of arc sprayed Al coating caused by rough morphology. • Electrochemical noise provides adequate estimates of galvanic behaviour

  9. Corrosion behaviour and galvanic coupling with steel of Al-based coating alternatives to electroplated cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Fasuba, O.A.; Yerokhin, A., E-mail: A.Yerokhin@sheffield.ac.uk; Matthews, A.; Leyland, A.

    2013-08-15

    The galvanic corrosion behaviour of bare steel coupled to steel with an Al–Zn flake inorganic spin coating, an Al-based slurry sprayed coating, an arc sprayed Al coating and electroplated cadmium has been investigated. The sacrificial and galvanic behaviour of the coatings was studied in 3.5 wt. % NaCl solution using open-circuit potential, potentiodynamic polarisation and electrochemical noise measurements. The coatings were characterised by scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction. Experimental results showed that the Al-based slurry sprayed coating exhibited an open-circuit potential closer to the steel substrate than other coatings, as well as a low corrosion current density and a more positive corrosion potential. In terms of the galvanic suitability of the investigated coatings for the steel substrate, both the Al–Zn flake inorganic spin coating and the Al-based slurry sprayed coating show low galvanic current, in comparison with the arc sprayed Al coating and electroplated cadmium. This behaviour confirms their superior cathodic protection capability and galvanic compatibility over other coatings tested. Electrochemical noise measurements provide accurate information on the coatings' galvanic behaviour, which can be complimented by the data obtained from superposition of potentiodynamic corrosion scans of the coating and bare steel, provided that the corrosion potential difference between the two materials does not exceed 300 mV. - Highlights: • Al-based slurry coating has best galvanic compatibility with steel. • Mg, Cr, P in Al-based slurry coating reinforce its corrosion resistance. • Ennoblement of Al–Zn flake coating compromises its cathodic protection. • Poor corrosion behaviour of arc sprayed Al coating caused by rough morphology. • Electrochemical noise provides adequate estimates of galvanic behaviour.

  10. Efficiency Criterion of Corrosion Inhibitors of Carbon Steel in Seawater

    OpenAIRE

    Habib, K.

    2014-01-01

    A criterion of the efficiency evaluation of corrosion inhibitors of metallic samples in aqueous solutions was proposed for the first time.The criterion was derived based on calculating the limit of ratio value of the resistivity of carbon steel sample in inhibited seawater (?ins) to the resistivity of the carbon steel sample in blank seawater (?s). In other words, the criterion; lim (?ins/?s) =1 will determine the efficiency of the corrosion inhibitor in the seawater when ?ins becomes equal (...

  11. Corrosion under stress of AISI 304 steel in thiocyanate solutions

    International Nuclear Information System (INIS)

    Corrosion susceptibility under stress of AISI 304 steel sensitized in a sodium thiocyanate solution has been studied and results were compared with those obtained with solutions of thiosulfate and tetrathionate. Sensitized steel type 304 is highly susceptible to corrosion when under intergranular stress (IGSCC) in thiocyanate solutions but the aggressiveness of this anion is less than that of the other sulphur anions studied (thiosulfate and tetrathionate). This work has been partly carried out in the Chemistry Department. (Author)

  12. Corrosion resistance properties of sintered duplex stainless steel

    OpenAIRE

    L.A. Dobrza?skI; Z. Brytan; M. Actis Grande; Rosso, M.

    2006-01-01

    Purpose: of this paper was to examine the corrosion resistance of duplex stainless steels using electrochemical methods in 1M NaCl solution. The influence of powder mixes preparation and cooling cycle after sintering on corrosion properties was evaluated.Design/methodology/approach: In presented study duplex stainless steels were obtained through powder metallurgy starting from austenitic, martensitic base powders by controlled addition of alloying elements, such as Cr, Ni, Mo and Cu. In the ...

  13. On the use of triazines as inhibitors of steel corrosion

    International Nuclear Information System (INIS)

    A possibility of using substandard pesticides as a raw materials for synthesis of a set of triazines and also using them as a inhibitors of acidic corrosion of steel 20, as well as additions to epoxy powder coatings is considered. It is shown that triazines studied are inhibitors of acidic corrosion of steel 20. 2,4-di(ethylamino)-6-phenylhydrazono-1,3,5-triazine (In 4) has a maximum inhibiting effect among the studied compounds

  14. Electrochemical Studies of Stainless Steel Corrosion in Peroxide Solutions

    Scientific Electronic Library Online (English)

    Ajay K., Singh; Vipin, Chaudhary; A., Sharma.

    2012-03-01

    Full Text Available Pollution control measures have resulted in replacement of chlorine by peroxide as bleaching chemical. Change of chemical affects corrosion aspects, the suitability of existing plant metallurgy and materials of construction of bleach plants. Accordingly long term immersion and electrochemical corros [...] ion tests were conducted on stainless steel 304L, 316L, 2205 and 6% Mo and mild steel in peroxide solutions of pH 10. The materials were tested for uniform corrosion, pitting and crevice corrosion and attack around the weld area. Corrosion attack estimated from long term immersion tests is found in agreement, by and large, with that analyzed from electrochemical test. E-pH diagrams drawn for water-peroxide system have been used to understand the corrosivity of the peroxide media. An attempt has been made to suggest a suitable material of construction for handling the test media on the basis of degree of corrosion attack on them and their cost and the mechanical properties.

  15. Passivation and Corrosion Behavior of Modified Ferritic-Pearlitic Railway Axle Steels

    Science.gov (United States)

    Moon, A. P.; Sangal, S.; Srivastav, Simant; Gajbhiye, N. S.; Mondal, K.

    2015-01-01

    Electrochemical polarization behavior of two newly developed ferritic-pearlitic railway axle steels (MS3 and MS6) and the standard Indian conventional axle steel has been studied in sodium borate buffer solution of pH 8.4 with and without the presence of NaCl. The polarization behavior of both the new axle steels shows close resemblance, whereas, different polarization behavior has been observed for the conventional axle steel. Electrochemical impedance spectroscopy measurements have clearly reflected significantly improved passivation behavior for the newly developed steels compared to that of the conventional axle steel. NaCl salt fog exposure tests have also shown superior corrosion resistance of the newly developed axle steels as compared to the conventional axle steel. Higher surface roughness on the corroded conventional axle steel has also been observed compared to the smoother surface in case of the new axle steels. Higher corrosion resistance of the new axle steels has been attributed to their finer microstructure and strongly adherent protective rusts.

  16. Corrosion behaviour and biocorrosion of galvanized steel water distribution systems.

    Science.gov (United States)

    Delaunois, F; Tosar, F; Vitry, V

    2014-06-01

    Galvanized steel tubes are a popular mean for water distribution systems but suffer from corrosion despite their zinc or zinc alloy coatings. First, the quality of hot-dip galvanized (HDG) coatings was studied. Their microstructure, defects, and common types of corrosion were observed. It was shown that many manufactured tubes do not reach European standard (NBN EN 10240), which is the cause of several corrosion problems. The average thickness of zinc layer was found at 41?m against 55?m prescribed by the European standard. However, lack of quality, together with the usual corrosion types known for HDG steel tubes was not sufficient to explain the high corrosion rate (reaching 20?m per year versus 10?m/y for common corrosion types). Electrochemical tests were also performed to understand the corrosion behaviours occurring in galvanized steel tubes. Results have shown that the limiting step was oxygen diffusion, favouring the growth of anaerobic bacteria in steel tubes. EDS analysis was carried out on corroded coatings and has shown the presence of sulphur inside deposits, suggesting the likely bacterial activity. Therefore biocorrosion effects have been investigated. Actually sulphate reducing bacteria (SRB) can reduce sulphate contained in water to hydrogen sulphide (H2S), causing the formation of metal sulphides. Although microbial corrosion is well-known in sea water, it is less investigated in supply water. Thus, an experimental water main was kept in operation for 6months. SRB were detected by BART tests in the test water main. PMID:24503139

  17. Corrosion Protection under Thermal Insulation

    OpenAIRE

    Sigbjørnsen, Karen

    2013-01-01

    Corrosion under insulation (CUI) is an extensive and costly problem for the petrochemical and chemical industry. Both good coatings to mitigate the problem and test methods to ensure the quality of these coatings are needed. In this thesis, four coatings; standard epoxy coating, epoxy phenolic coating, titanium modified inorganic copolymer (TMIC) and thermally sprayed aluminium (TSA), were tested for their ability to mitigate the problem. To simulate the CUI conditions, several test methods m...

  18. Spatial distribution of crystalline corrosion products formed during corrosion of stainless steel in concrete

    KAUST Repository

    Serdar, Marijana

    2015-05-01

    © 2015 Elsevier Ltd All rights reserved. The mineralogy and spatial distribution of nano-crystalline corrosion products that form in the steel/concrete interface were characterized using synchrotron X-ray micro-diffraction (μ-XRD). Two types of low-nickel high-chromium reinforcing steels embedded into mortar and exposed to NaCl solution were investigated. Corrosion in the samples was confirmed by electrochemical impedance spectroscopy (EIS). μ-XRD revealed that goethite (α-FeOOH) and akaganeite (β-FeOOH) are the main iron oxide-hydroxides formed during the chloride-induced corrosion of stainless steel in concrete. Goethite is formed closer to the surface of the steel due to the presence of chromium in the steel, while akaganeite is formed further away from the surface due to the presence of chloride ions. Detailed microstructural analysis is shown and discussed on one sample of each type of steel.

  19. Fretting corrosion of steels for lead alloys cooled ADS

    International Nuclear Information System (INIS)

    Fretting is a particular type of wear that is expected to occur in a molten lead alloy cooled ADS due to the flow induce vibrations and that mainly affects fuel claddings and heat exchanger tubes. A dedicated facility (i.e. FRETHME) was designed and realized to investigate for the first time fretting in liquid lead alloys at reactor relevant conditions. Several fretting tests, were performed on candidate steels such as the f/m T91 steel, the austenitic 15-15Ti steel and Al surface alloyed T91 (GESA-T91). The experimental outcomes highlighted that the fretting damage increases with the increasing number of cycles/time and temperature. Fretting interacts with the corrosion mechanisms occurring in liquid Pb alloys (fretting corrosion) and destabilizes the corrosion barriers, favoring e.g. dissolution attacks. Due to the favorable wear and corrosion resistance properties of the surface alloyed layer, GESA-T91 steel showed the best fretting corrosion behavior up to 550 °C. On the contrary, due to the high Ni content, the 15-15Ti steel is affected by dissolution enhanced fretting; while oxidation enhanced fretting characterizes T91 steel at temperatures higher than 500 °C. In this respect, dedicated tests suggested that besides the use of aluminized steels, possible countermeasures to mitigate the fretting impact are the use of pre-oxidized components and Ni-enriched liquid Pb

  20. Corrosion Protection Properties of 4-[(E)-[(2,4-Dihydroxy phenyl)methylidene] amino]-6-methyl-3-sulfanylidene-2,3,4,5-tetrahydro-1,2,4-triazin-5-one [DMSTT] Toward Mild Steel in Sulfuric Acid

    Science.gov (United States)

    John, Sam; Joseph, Abraham

    2013-02-01

    The inhibition of mild steel corrosion in aerated 0.5 N H2SO4 solution was investigated using potentiodynamic polarization studies (Tafel), linear polarization studies, electrochemical impedance spectroscopy studies, adsorption studies, and surface morphological studies. The effect of inhibitor concentration on corrosion rate, the effect of temperature, degree of surface coverage, adsorption kinetics, and surface morphology are investigated. The inhibition efficiency increased markedly with increase in the additive concentration and decreased slightly with increasing temperature. The presence of DMSTT decrease the double-layer capacitance and increase the charge transfer resistance. The value of activation energy ( E a) of metal corrosion, adsorption equilibrium constant ( K ads), and free energy of adsorption (? G ads) were calculated from the temperature dependence of corrosion current. The adsorption of inhibitor molecule on mild steel surface follow Langmuir isotherm. DMSTT offers excellent inhibition properties and acts as a mixed-type inhibitor.

  1. Electrochemical and corrosion behavior of carbon steel in SULFIRAN process

    International Nuclear Information System (INIS)

    Corrosion behavior of carbon steel was evaluated in Fe-EDTA solution designed to be used in acid gas treatment process (SULFIRAN plant) in the temperature range between 35 deg. C and 45 deg. C. Electrochemical techniques, i.e. polarization curves and electrochemical impedance spectroscopy (EIS) were applied for laboratory evaluations. Linear polarization resistance (LPR) and weight loss techniques were used to determine the corrosion rate for pilot tests. In addition, several surface analysis techniques such as XRD, XRF, SEM and optical microscopy were employed to determine the corrosion morphology. Metallurgical and SEM investigations of the carbon steel corrosion showed corrosion-induced damages in SULFIRAN process. The corrosion demonstrated in the forms of severe uniform corrosion, wide shallow pits formation, under deposit corrosion, hydrogen micro-void formation, and hydrogen induced disbonding between the interfaces of the inclusion (MnS) and metal matrix. The corrosion rate of carbon steel alloy is predicted to be very high (>200 mils per year or mpy) in this process.

  2. Electrochemical and corrosion behavior of carbon steel in SULFIRAN process

    Energy Technology Data Exchange (ETDEWEB)

    Neshati, J. [Corrosion Department, Research Institute of Petroleum Industry (RIPI), P.O. Box 18745-4163, Tehran (Iran, Islamic Republic of)], E-mail: Neshatyj@ripi.ir; Abedi, S. Sh. [Corrosion Department, Research Institute of Petroleum Industry (RIPI), P.O. Box 18745-4163, Tehran (Iran, Islamic Republic of); Forsat, Kh. [Engineering and Process Development Division, Research Institute of Petroleum Industry (RIPI), Tehran (Iran, Islamic Republic of); Jenab, M. Hosseini [Gas Science Department, Research Institute of Petroleum Industry (RIPI), Tehran (Iran, Islamic Republic of); Mirfendereski, S. [Corrosion Department, Research Institute of Petroleum Industry (RIPI), P.O. Box 18745-4163, Tehran (Iran, Islamic Republic of)

    2009-05-15

    Corrosion behavior of carbon steel was evaluated in Fe-EDTA solution designed to be used in acid gas treatment process (SULFIRAN plant) in the temperature range between 35 deg. C and 45 deg. C. Electrochemical techniques, i.e. polarization curves and electrochemical impedance spectroscopy (EIS) were applied for laboratory evaluations. Linear polarization resistance (LPR) and weight loss techniques were used to determine the corrosion rate for pilot tests. In addition, several surface analysis techniques such as XRD, XRF, SEM and optical microscopy were employed to determine the corrosion morphology. Metallurgical and SEM investigations of the carbon steel corrosion showed corrosion-induced damages in SULFIRAN process. The corrosion demonstrated in the forms of severe uniform corrosion, wide shallow pits formation, under deposit corrosion, hydrogen micro-void formation, and hydrogen induced disbonding between the interfaces of the inclusion (MnS) and metal matrix. The corrosion rate of carbon steel alloy is predicted to be very high (>200 mils per year or mpy) in this process.

  3. Effect of segregation bands on corrosion of steel plate for ship hull

    Directory of Open Access Journals (Sweden)

    M. Mazur

    2010-07-01

    Full Text Available Despite significant progress in the manufacturing of sheet metal ships carried both by optimizing the chemical compositions of steel mills as well as rolling and heat treatment, it still fails to remove the effects of persistent segregation. As a result we observed anisotropy of mechanical properties of the material which essentially complicates the process of construction for shipbuilding industry. Anisotropy of mechanical properties occurring in sheet metal hull is even more dangerous, that during their work, they are exposed to continuous exposure variable charges arising from sea surface waves. Another factor weakening the resistance to cracking metal ship is sea-water, which in the surface layer is highly aerated and very aggressive corrosion. The purpose of this study is to clarify the role of the segregation bands in the process of corrosion of low alloy steels used for ship hull. It was estimate a rate of corrosion in aerated sea water areas of the metal with or without segregation bands. After corrosion tests were made observations of specimens surfaces. Inside the segregation bands were found phosphorus. The contents of it were exceeded the average this element content in the steel. At the same time areas of the sheet metal with segregation bands were slowly corroded than areas without bands, although the changes of corrosion rate was similar in nature.Corrosion activity of rich in phosphorus segregation band is similar to phosphate corrosion inhibitors. These are effective in the presenceof chloride in seawater to form a protective layer that protects against corrosion segregation band. Under the observation on scanningelectron microscope there was no change in the appearance of surface samples after corrosion tests. A future direction of research will be estimate the stress corrosion in the same species – with and without segregation bands.

  4. A New Green Ionic Liquid-Based Corrosion Inhibitor for Steel in Acidic Environments.

    Science.gov (United States)

    Atta, Ayman M; El-Mahdy, Gamal A; Al-Lohedan, Hamad A; Ezzat, Abdel Rahman O

    2015-01-01

    This work examines the use of new hydrophobic ionic liquid derivatives, namely octadecylammonium tosylate (ODA-TS) and oleylammonium tosylate (OA-TS) for corrosion protection of steel in 1 M hydrochloric acid solution. Their chemical structures were determined from NMR analyses. The surface activity characteristics of the prepared ODA-TS and OA-TS were evaluated from conductance, surface tension and contact angle measurements. The data indicate the presence of a double bond in the chemical structure of OA-TS modified its surface activity parameters. Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) measurements, scanning electron microscope (SEM), Energy dispersive X-rays (EDX) analysis and contact angle measurements were utilized to investigate the corrosion protection performance of ODA-TS and OA-TS on steel in acidic solution. The OA-TS and ODA-TS compounds showed good protection performance in acidic chloride solution due to formation of an inhibitive film on the steel surface. PMID:26091073

  5. Corrosion and potentiostatic hydrogenation of carbon steels in carbonate and sulfide solutions

    International Nuclear Information System (INIS)

    Corrosion behaviour and hydrogenation of two structural carbon steel at controlled potentials in the interval of -1.4 V-+0.4 V in a carbonate-bicarbonate solution (pH 9.4) on the free oxygen access, solution deaeration with argon and saturation with hydrogen sulfide (pH 8.5) are studied. It is established that in the deaerated solution on the potential cathode shift is realized the steel cathode protection where as in carbonate-sulfide solution is found increasing the corrosion rate. 6 refs., 3 figs

  6. Corrosion by concentrated sulfuric acid in carbon steel pipes and tanks: state of the art

    Energy Technology Data Exchange (ETDEWEB)

    Panossian, Zehbour; Almeida, Neusvaldo Lira de; Sousa, Raquel Maria Ferreira de [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil); Pimenta, Gutemberg de Souza [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas e Desenvolvimento (CENPES); Marques, Leandro Bordalo Schmidt [PETROBRAS Engenharia, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    PETROBRAS, allied to the policy of reduction of emission of pollutants, has been adjusting the processes of the new refineries to obtain products with lower sulfur content. Thus, the sulfur dioxide, extracted from the process gases of a new refinery to be built in the Northeast, will be used to produce sulfuric acid with concentration between (94-96) %. This acid will be stored in carbon steel tanks and transported through a buried 8-km carbon steel pipe from the refinery to a pier, where it will be loaded onto ships and sent to the consumer markets. Therefore, the corrosion resistance of carbon steel by concentrated acid will become a great concern for the mentioned storage and transportation. When the carbon steel comes into contact with concentrated sulfuric acid, there is an immediate acid attack with the formation of hydrogen gas and ferrous ions which, in turn, forms a protective layer of FeSO{sub 4} on the metallic surface. The durability of the tanks and pipes made of carbon steel will depend on the preservation of this protective layer. This work presents a review of the carbon steel corrosion in concentrated sulfuric acid and discusses the preventive methods against this corrosion, including anodic protection. (author)

  7. Heat transfer corrosion of stainless steel in nitric acid

    International Nuclear Information System (INIS)

    Full text of publication follows: In nuclear reprocessing plants, interest is focused on the behaviour of stainless steels in nitric acid solutions, the principal heated process vessels being spent-fuel dissolvers and evaporators. The corrosion of stainless steels by nitric acid is known to be complex, being affected by a host of metallurgical and environmental factors. Amongst the latter, temperature exerts a strong effect, the corrosion rate typically doubling for a temperature increase of 7-10 C depending on the exact liquor composition. The type of corrosion which occurs is intergranular whereby grain boundaries between individual stainless steel crystals are subject to attack. This is due to differing local concentrations of alloying metals and interstitial contaminants at the grain boundaries and eventually causes entire crystals to detach from the bulk steel. Less well understood is what, if any, effect a temperature gradient between the liquor and the stainless steel vessel exerts on this corrosion mechanism and therefore the corrosion rate of dissolvers and evaporators exposed to these conditions. Possible effects include changing mass transport mechanisms to the surface of the steel, a temperature gradient could also influence what corrosion products are formed at the surface which in turn has a considerable affect on the passivity of the steel. This project is concerned with the corrosion rate of stainless steel heat transfer surfaces contacted by nitric acid solutions and comparing this with corrosion rate data obtained isothermally at equivalent effective surface temperatures. This comparison will confirm or deny whether additional corrosion effects occur. A wide range of heat transfer conditions will be tested using a variety of nitric acid liquors. Using weight loss and electrochemical techniques it is possible to deduce the corrosion rate as a function of time. Various microscopy techniques are also employed to provide a qualitative understanding of the corrosion mechanisms involved. This has been achieved under isothermal conditions. It is far more challenging to design and construct experimental apparatus which allow a comparison with heat transfer surfaces. Such a novel test rig was completed and commissioned in January 2009. Due to the timescales of the procedures involved and the complexity and originality of the apparatus a comparison of corrosion rates is not imminent

  8. 49 CFR 192.463 - External corrosion control: Cathodic protection.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Cathodic protection... for Corrosion Control § 192.463 External corrosion control: Cathodic protection. (a) Each cathodic protection system required by this subpart must provide a level of cathodic protection that complies with...

  9. Influence of sulphur content, sulphur distribution and deoxidation practice on the corrosion of steel in seawater

    International Nuclear Information System (INIS)

    Seven steels, mainly differing by the sulphur content have been exposed for two years in the splash water-, alternate immersion-, and continuous immersion zones of the test stand Helgoland of the Verein Deutscher Eisenhuettenleute. High sulphur contents led in the splash water zone to a markedly higher corrosion attack. This is attributable to the formation of sulphate clusters, reducing the protective effect of formed rust layers. In addition, the sulphur content influences to a slight extent also the formation of the surface layers in the alternate immersion zone. In the continuous immersion zone, there is no evidence of any influence of the sulphur on corrosion. The deoxidation practice and the distribution of the sulphur had no bearing on the corrosion rates. A localy increased corrosion attack, being in a causal connection with the sulphides in the steel, was not observed. (orig./RW)

  10. Corrosion and Wear Resistance of Carbon Films Obtained by Electrodeposition on Ferritic Stainless Steel

    Scientific Electronic Library Online (English)

    Henrique Ribeiro Piaggio, Cardoso; Tiago, Falcade; Sandra Raquel, Kunst; Célia Fraga, Malfatti.

    2015-04-01

    Full Text Available In improving the corrosion and hardness proprieties of ferritic stainless steel, the use of protective coatings becomes an interesting alternative. In this study, a carbon layer was deposited on AISI 430 by electrodeposition using N,N-dimethylformamide with the addition of an organic dopant as the e [...] lectrolyte. The AISI 430 stainless steel was pretreated by anodization aiming to optimize the film anchoring. The obtained films were characterized by atomic force microscopy, by scanning electron microscopy and by optical interferometry. The microstructural characterization of the films was obtained by Raman Spectroscopy. The corrosion resistance was evaluated by open circuit potential and by potentiodynamic polarization. The friction test and the scratch test were performed to evaluate the mechanical properties. The Raman spectroscopy showed the presence of an amorphous carbon film. The films improved the corrosion resistance of stainless steel. In addition, on the wear analysis the coating showed a good adhesion on the substrate.

  11. Inhibition of steel corrosion by electrosynthesized poly(o-anisidine)-dodecylbenzenesulfonate coatings

    International Nuclear Information System (INIS)

    Poly(o-anisidine)-dodecylbenzenesulfonate (POA-DBSA) coatings were synthesized on stainless steel from aqueous solution containing o-anisidine and dodecylbenzene sulfonic acid by using cyclic voltammetry. These coatings were characterized by Fourier transform infrared spectroscopy (FTIR), UV-vis absorption spectroscopy, scanning electron microscopy (SEM) and cyclic voltammetry (CV). Corrosion tests of these coatings were carried out in aqueous 3% NaCl solution by using open circuit potential (OCP) measurements, potentiodynamic polarization technique, cyclic potentiodynamic polarization measurements and electrochemical impedance spectroscopy (EIS). The results reveal that POA-DBSA acts as a corrosion protective coating on steel and reduces the corrosion rate (CR) of steel almost by a factor of 14.5.

  12. Inhibition of steel corrosion by electrosynthesized poly(o-anisidine)-dodecylbenzenesulfonate coatings

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhari, Sudeshna, E-mail: sudeshna6480@yahoo.co.i [Department of Physics, North Maharashtra University, Jalgaon 425001, Maharashtra (India); Patil, P.P. [Department of Physics, North Maharashtra University, Jalgaon 425001, Maharashtra (India)

    2010-09-01

    Poly(o-anisidine)-dodecylbenzenesulfonate (POA-DBSA) coatings were synthesized on stainless steel from aqueous solution containing o-anisidine and dodecylbenzene sulfonic acid by using cyclic voltammetry. These coatings were characterized by Fourier transform infrared spectroscopy (FTIR), UV-vis absorption spectroscopy, scanning electron microscopy (SEM) and cyclic voltammetry (CV). Corrosion tests of these coatings were carried out in aqueous 3% NaCl solution by using open circuit potential (OCP) measurements, potentiodynamic polarization technique, cyclic potentiodynamic polarization measurements and electrochemical impedance spectroscopy (EIS). The results reveal that POA-DBSA acts as a corrosion protective coating on steel and reduces the corrosion rate (CR) of steel almost by a factor of 14.5.

  13. Structural and phase heterogeneity of cast austenitic corrosion resisting steels

    International Nuclear Information System (INIS)

    Structure of large-size castings of austenitic corrosion-resistant steel type 08Kh18N10T was under study. Consideration was given to peculiar features of crystallization as well as to distribution of ?-ferrite, austenite- and ferrite forming elements and nonmetallic inclusions in steel castings. Casting defects and causes of their formation were investigated

  14. Corrosion of reinforcing steel in concrete - electrochemical laboratory experiments

    International Nuclear Information System (INIS)

    Steel bars with electric connections were embedded in prisms of six different concrete compositions. The test specimens were stored partly immersed into synthetic sea water or tap water over a period of about two years. Potential monitoring and polarisation experiments were used to estimate the corrosion rates of the steel. (author) 4 refs., 6 figs., 3 tabs

  15. In situ 3D monitoring of corrosion on carbon steel and ferritic stainless steel embedded in cement paste

    KAUST Repository

    Itty, Pierre-Adrien

    2014-06-01

    In a X-ray microcomputed tomography study, active corrosion was induced by galvanostatically corroding steel embedded in cement paste. The results give insight into corrosion product build up, crack formation, leaching of products into the cracks and voids, and differences in morphology of corrosion attack in the case of carbon steel or stainless steel reinforcement. Carbon steel was homogeneously etched away with a homogeneous layer of corrosion products forming at the steel/cement paste interface. For ferritic stainless steel, pits were forming, concentrating the corrosion products locally, which led to more extensive damage on the cement paste cover. © 2014 Elsevier Ltd.

  16. Corrosion behaviour of galvanized steel and electroplating steel in aqueous solution: AC impedance study and XPS

    International Nuclear Information System (INIS)

    The efficiency of a new triazole derivative, namely, 2-{(2-hydroxyethyl)[(4-methyl-1H-1,2,3-benzotriazol-1-yl)methyl]amino} ethanol (TTA) has been studied for corrosion inhibition of galvanized steel and electroplating steel in aqueous solution. Corrosion inhibition was studied using electrochemical impedance spectroscopy (EIS). These studies have shown that TTA was a very good inhibitor. Data obtained from EIS show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPE) has been used. The corrosion behaviour of galvanized steel and electroplating steel in aqueous solution was also investigated in the presence of 4-methyl-1H-benzotriazole (TTA unsubstituted) by EIS. These studies have shown that the ability of the molecule to adsorb on the steel surface was dependent on the group in triazole ring substituent. X-ray photoelectron spectroscopy surface analysis with TTA shows that it chemisorbed on surface of galvanized steel and electroplating steel

  17. Ranitidine Drugs as Non-Toxic <span class="hlt">Corrosion</span> Inhibitors for Mild <span class="hlt">Steel</span> in Hydrochloric Acid Medium</span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>R.S. Abdel Hameed</p> <p>2011-01-01</p> <p>Expired ranitidine was tested as a <span class="hlt">corrosion</span> inhibitor for mild <span class="hlt">steel</span> in 1 M HCl using different techniques: weight loss, potentiodynamic polarization, open circuit potential and electrochemical impedance spectroscopy. The polarization resistance (Rp) value increased with increase in the concentration of the inhibitor. Results obtained revealed that ranitidine performed excellently as a <span class="hlt">corrosion</span> inhibitor for mild <span class="hlt">steel</span> in this medium at 303 K. The <span class="hlt">protection</span> efficiency increased with increa...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:30000665','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:30000665"><span id="translatedtitle">Atmospheric <span class="hlt">corrosion</span> of carbon <span class="hlt">steel</span> resulting from short term exposures</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The study of <span class="hlt">corrosion</span> products from short term atmospheric exposures of carbon <span class="hlt">steel</span>, is very important to understand the processes that lead to <span class="hlt">corrosion</span> of <span class="hlt">steels</span>, and ultimately improve the performance of such <span class="hlt">steel</span> in highly <span class="hlt">corrosive</span> environments. Many regions along the Gulf of Mexico have extremely <span class="hlt">corrosive</span> environments due to high mean annual temperature, humidity, time-of-wetness and every high atmospheric pollutants. The process the formation of <span class="hlt">corrosion</span> products resulting from short term exposure of carbon <span class="hlt">steel</span>, both as a function of environmental conditions and exposure time, has been investigated. Two sets of coupons were exposed at marine and marine locations, in Campeche, Mexico. Each set was exposed between 1 and 12 months to study the <span class="hlt">corrosion</span> as a function of time. During the exposure periods, the relative humidity, rainfall, mean temperature, wind speed and wind direction were monitored along with the chloride and sulfur dioxide concentrations in the air. The corroded coupons were analyzed by Moessbauer, Raman, Infrared spectroscopies and X-ray diffraction in order to completely identify the oxides and map their location in the <span class="hlt">corrosion</span> coating. Scattering and transmission Moessbauer analysis showed some layering of the oxides with lepidocrocite and akaganeite closer to the surface. The fraction of akaganeite phase increased at sites with higher chloride concentrations. A detailed analysis on the development of the oxide phases as a function of exposure time and environmental conditions will be presented. (Author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cdsweb.cern.ch/record/2043888','WWSCERN-EN'); return false;" href="http://cdsweb.cern.ch/record/2043888"><span id="translatedtitle"><span class="hlt">Corrosion</span> of constructional <span class="hlt">steels</span> in marine and industrial environment frontier work in atmospheric <span class="hlt">corrosion</span></span></a></p> <p><a target="_blank" href="http://cdsweb.cern.ch/">CERN Document Server</a></p> <p>Saha, Jayanta Kumar</p> <p>2012-01-01</p> <p>An exhaustive research study on atmospheric <span class="hlt">corrosion</span> of structural <span class="hlt">steel</span>, this important publication, with numerous illustrations, details investigative methods for a better understanding of the degradation process, and mixes for high-performance paints.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=354453','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=354453"><span id="translatedtitle"><span class="hlt">Corrosion</span> of <span class="hlt">steel</span> H piles in decomposed granite</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Wong, I.H. [Mitic Associates, Cashew Heights (Singapore); Law, K.H. [Land Transportation Authority, Singapore (Singapore)</p> <p>1999-06-01</p> <p>To study the <span class="hlt">corrosion</span> of <span class="hlt">steel</span> H piles in a completely decomposed granite, piles were exposed by excavation 22 years after their installation. The thickness of the pile sections was measured. The average <span class="hlt">corrosion</span> rate of the <span class="hlt">steel</span> piles was estimated to be 0.011 mm/year, and the maximum <span class="hlt">corrosion</span> rate was estimated to be 0.015--0.018 mm/year. The rates are low. The results confirm the conclusions derived from tests done in places with temperate climate that <span class="hlt">steel</span> piles installed in undisturbed, native soils undergo little <span class="hlt">corrosion</span>. Thus, such conclusions are also applicable to the completely decomposed granite in a place like Singapore with high year-round temperatures ranging from 25 to 35 C.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:30000883','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:30000883"><span id="translatedtitle">Electrochemical evaluation of crevice <span class="hlt">corrosion</span> in stainless <span class="hlt">steels</span></span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>An electrochemical method for the evaluation of crevice <span class="hlt">corrosion</span> in stainless <span class="hlt">steels</span> is described. Specimens are carefully abraded in order to give a large number of microcrevices when the specimen is placed in contact with a rubber o-ring. Twelve specimens are tested simultaneously in a purpose-built electrochemical cell. A constant potential is applied to the specimens and the temperature automatically raised at intervals until a current increase indicates the onset of crevice <span class="hlt">corrosion</span> and thereby defines the critical crevice <span class="hlt">corrosion</span> temperature (CCT). Testing has been performed on a wide range of stainless <span class="hlt">steels</span> in 3.5% NaCl at +700 mV SCE. The temperature was raised by 5 C every 70 minutes. Results show good reproducibility with a typical standard deviation of below 5 C. There is also excellent agreement with the ranking of crevice <span class="hlt">corrosion</span> resistance for different <span class="hlt">steel</span> grades which is obtained by immersion testing in 6% FeCl3 solution. (orig.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:14801799','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:14801799"><span id="translatedtitle"><span class="hlt">Corrosion</span> of <span class="hlt">steel</span> 0Kh18N10T</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p><span class="hlt">Steel</span> 0Kh18N10T is used for the manufacture of heat transfer tubes and collectors of steam generators for WWER nuclear power plants. The surface <span class="hlt">corrosion</span> rate of this <span class="hlt">steel</span> was studied in hydrochloric acid at different concentrations at a normal temperature of 20 degC. Three types of the <span class="hlt">steel</span> heat treatment were chosen. In the case of tubes the effect of explosion and deformations on <span class="hlt">corrosion</span> rate was also studied. A strong dependence was found on the concentration of hydrochloric acid: <span class="hlt">corrosion</span> losses increased exponentially at concentrations higher than 10%. On the other hand, no dependence was found of the <span class="hlt">corrosion</span> rate on the heat treatment technology or on the explosion or deformation treatment of the material. (Z.M.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:21086102','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:21086102"><span id="translatedtitle">Microbiologically influenced <span class="hlt">corrosion</span> of high molybdenum austenitic stainless <span class="hlt">steel</span></span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Extensive literature exists documenting laboratory and field studies of <span class="hlt">corrosion</span> of the 300 series stainless <span class="hlt">steels</span> by bacteria. There is, however, little data confirming similar microbiologically influenced <span class="hlt">corrosion</span> (MIC) of higher alloy stainless <span class="hlt">steels</span>, which are thought by some to be immune. This paper presents a case history of a UNS NO8904 (904L) heat exchanger where marine bacterial attack was determined to be a factor in the <span class="hlt">corrosion</span> failure. On-site sampling and testing confirmed the existence of this type of attack and developed a program of biocide treatment. Subsequent laboratory studies were undertaken to confirm the bacteria can induce and propagate pitting <span class="hlt">corrosion</span> of a high molybdenum austenitic stainless <span class="hlt">steel</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:22085644','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:22085644"><span id="translatedtitle">Microbially influenced <span class="hlt">corrosion</span> of stainless <span class="hlt">steels</span> in nuclear power plants</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>This paper reviews the components, causative agents, <span class="hlt">corrosion</span> sites, and potential failure modes of stainless <span class="hlt">steel</span> components susceptible to microbially influenced <span class="hlt">corrosion</span> (MIC). The stainless <span class="hlt">steel</span> components susceptible to MIC are located in the reactor coolant, emergency, and reactor auxiliary systems, and in many plants, in the feedwater train and condenser. The authors assessed the areas of most high occurrence of <span class="hlt">corrosion</span> and found the sites most susceptible to MIC to the heat-affected zones in the weldments of sensitized stainless <span class="hlt">steel</span>. Pitting is the predominant MIC <span class="hlt">corrosion</span> mechanisms, caused by sulfur reducing bacteria (SRB). Also discussed is the current status of the diagnostic, preventive, and mitigation techniques, including use of improved water chemistry, alternate materials, and improved thermomechanical treatments. 37 refs., 3 figs</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:43049721','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:43049721"><span id="translatedtitle">Experimental and theoretical studies of thiazoles as <span class="hlt">corrosion</span> inhibitors for mild <span class="hlt">steel</span> in sulphuric acid solution</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Graphical abstract: The inhibition effect of 2-amino-5-mercapto-1,3,4-thiadiazole and 2-mercaptothiazoline on mild <span class="hlt">steel</span> <span class="hlt">corrosion</span> in 1.0 M H2SO4 was studied using electrochemical techniques. The effects of the presence of extra NH2 group and N atom in 2A5MT on the ability to act as <span class="hlt">corrosion</span> inhibitors were investigated by theoretical calculations. Highlights: ? The inhibition effects of thiazoles on mild <span class="hlt">steel</span> <span class="hlt">corrosion</span> in 1.0 M H2SO4 were studied. ? It was shown that both thiazole compounds act as excellent <span class="hlt">corrosion</span> inhibitors for mild <span class="hlt">steel</span>. ? The high inhibition efficiency was attributed to the adsorption of the inhibitor molecules on the metal surface. ? Langmuir adsorption isotherm exhibited the best fit to the experimental data. ? Quantum chemical calculations show there is a correlation between inhibitive property and molecular parameters. - Abstract: The inhibition effects of 2-amino-5-mercapto-1,3,4-thiadiazole (2A5MT) and 2-mercaptothiazoline (2MT) on mild <span class="hlt">steel</span> <span class="hlt">corrosion</span> in 1.0 M H2SO4 were studied with potentiodynamic polarization, linear polarization resistance and electrochemical impedance spectroscopy techniques. It was shown that both 2A5MT and 2MT act as good <span class="hlt">corrosion</span> inhibitors for mild <span class="hlt">steel</span> <span class="hlt">protection</span>. The high inhibition efficiencies were attributed to the simple blocking effect by adsorption of inhibitor molecules on the <span class="hlt">steel</span> surface. The effects of the presence of extra NH2 group and N atom in 2A5MT on the ability to act as <span class="hlt">corrosion</span> inhibitors were investigated by theoretical calculations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:19101532','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:19101532"><span id="translatedtitle">Analysis of <span class="hlt">corrosion</span> data for carbon <span class="hlt">steels</span> in simulated salt repository brines and acid chloride solutions at high temperatures</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Carbon <span class="hlt">steel</span> is currently the leading candidate material for fabrication of a container for isolation of high level nuclear waste in a salt repository. Since brine entrapped in the bedded salt can migrate to the container by several transport processes, <span class="hlt">corrosion</span> is an important consideration in the long-term performance of the waste package. A detailed literature search was performed to compile relevant <span class="hlt">corrosion</span> data for carbon <span class="hlt">steels</span> in anoxic acid chloride solutions, and simulated salt repository brines at temperatures between ? 20 and 4000C. The hydrolysis of Mg2+ ions in simulated repository brines containing high magnesium concentrations causes acidification at temperatures above 250C, which, in turn, influences the <span class="hlt">protective</span> nature of the magnetite <span class="hlt">corrosion</span> product layer on carbon <span class="hlt">steel</span>. The <span class="hlt">corrosion</span> data for the <span class="hlt">steels</span> were analyzed, and an analytical model for general <span class="hlt">corrosion</span> was developed to calculate the amount of penetration (i.e., wall thinning) as a function of time, temperature, and the pressure of <span class="hlt">corrosion</span> product hydrogen than can build up during exposure in a closed system (e.g., a sealed capsule). Both the temperature and pressure dependence of the <span class="hlt">corrosion</span> rate of <span class="hlt">steels</span> in anoxic acid chloride solutions indicate that the rate-controlling partial reaction is the cathodic reduction of water to form hydrogen. Variations in the composition and microstructure of the <span class="hlt">steels</span> or the concentration of the ionic species in the chloride solutions (provided that they do not change the pH significantly) do not appear to strongly influence the <span class="hlt">corrosion</span> rate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=doajarticles::612beb9a4a15fa6bf7a18befb81aef95','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=doajarticles::612beb9a4a15fa6bf7a18befb81aef95"><span id="translatedtitle"><span class="hlt">Corrosion</span> resistance of high-manganese austenitic <span class="hlt">steels</span></span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>A. Grajcar; S. Ko?odziej,; W. Krukiewicz</p> <p>2010-01-01</p> <p>Purpose: The aim of the paper is to compare the <span class="hlt">corrosion</span> resistance of two new-developed high-manganese austenitic <span class="hlt">steels</span> in 1N H2SO4 and 3.5% NaCl solutions.Design/methodology/approach: The <span class="hlt">steels</span> used for the investigation were thermo-mechanically rolled and then solution heat-treated from a temperature of 850°C. <span class="hlt">Corrosion</span> resistance of investigated <span class="hlt">steels</span> was examined using the immersion test. The specimens were weighed and dipped in the prepared solutions for 100 h. After the test, the p...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=od_______119::9a94fd9791fdd92a107f17ecf6383901','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=od_______119::9a94fd9791fdd92a107f17ecf6383901"><span id="translatedtitle"><span class="hlt">Corrosion</span> fatigue of a superduplex stainless <span class="hlt">steel</span> weldment</span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>Comer, Anthony John</p> <p>2004-01-01</p> <p>Superduplex stainless <span class="hlt">steels</span> have superior mechanical and <span class="hlt">corrosion</span> properties compared to austenitic stainless <span class="hlt">steels</span> such as the grade 300 series. This is a result of a microstructure consisting of roughly equal percentages of austenite (y) and ferrite (a) and negligible inclusion content. As a result, super duplex stainless <span class="hlt">steels</span> are increasingly being used in the offshore oil and gas industries. It is also envisaged that they will find application in the emergent renewable energy sec...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:46014486','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:46014486"><span id="translatedtitle">Investigation of high temperature <span class="hlt">corrosion</span> behavior on 304L austenite stainless <span class="hlt">steel</span> in <span class="hlt">corrosive</span> environments</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>In this work, 304L stainless <span class="hlt">steel</span> samples were exposed at 700 °C for 10hrs in different <span class="hlt">corrosive</span> environments; dry oxygen, molten salt, and molten salt + dry oxygen. The <span class="hlt">corrosion</span> behavior of samples was analyzed using weight change measurement technique, optical microscope (OM) and Scanning Electron Microscope (SEM) equipped with Energy Dispersive X-ray (EDX). The existence phases of corroded sample were determined using X-ray Diffraction (XRD). The lowest <span class="hlt">corrosion</span> rate was recorded in dry oxygen while the highest was in molten salt + dry oxygen environments with the value of 0.0062 mg/cm2 and ?13.5225 mg/cm2 respectively. The surface morphology of sample in presence of salt mixture showed scale spallation. Oxide scales of Fe3O4, Fe2O3 were the main phases developed and detected by XRD technique. Cr2O3 was not developed in every sample as <span class="hlt">protective</span> layers but chromate-rich oxide was developed. The cross-section analysis found the oxide scales were in porous, thick and non-adherent that would not an effective barrier to prevent from further degradation of alloy. EDX analysis also showed the Cr-element was low compared to Fe-element at the oxide scale region</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=22308313','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=22308313"><span id="translatedtitle">Investigation of high temperature <span class="hlt">corrosion</span> behavior on 304L austenite stainless <span class="hlt">steel</span> in <span class="hlt">corrosive</span> environments</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Sahri, M. I.; Othman, N. K.; Samsu, Z.; Daud, A. R. [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi Selangor (Malaysia)</p> <p>2014-09-03</p> <p>In this work, 304L stainless <span class="hlt">steel</span> samples were exposed at 700 °C for 10hrs in different <span class="hlt">corrosive</span> environments; dry oxygen, molten salt, and molten salt + dry oxygen. The <span class="hlt">corrosion</span> behavior of samples was analyzed using weight change measurement technique, optical microscope (OM) and Scanning Electron Microscope (SEM) equipped with Energy Dispersive X-ray (EDX). The existence phases of corroded sample were determined using X-ray Diffraction (XRD). The lowest <span class="hlt">corrosion</span> rate was recorded in dry oxygen while the highest was in molten salt + dry oxygen environments with the value of 0.0062 mg/cm{sup 2} and ?13.5225 mg/cm{sup 2} respectively. The surface morphology of sample in presence of salt mixture showed scale spallation. Oxide scales of Fe{sub 3}O{sub 4}, Fe{sub 2}O{sub 3} were the main phases developed and detected by XRD technique. Cr{sub 2}O{sub 3} was not developed in every sample as <span class="hlt">protective</span> layers but chromate-rich oxide was developed. The cross-section analysis found the oxide scales were in porous, thick and non-adherent that would not an effective barrier to prevent from further degradation of alloy. EDX analysis also showed the Cr-element was low compared to Fe-element at the oxide scale region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=20525181','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=20525181"><span id="translatedtitle">Steam <span class="hlt">corrosion</span> resistance of new 12% Cr ferritic boiler <span class="hlt">steels</span></span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Lepingle, V.; Louis, G. [Ecole des Mines de Douai, Douai (France); Petelot, D. [Centre de Recherche Vallourec, Aulnoye Aymeries (France); Lefebvre, B.; Vandenberghe, B. [Vallourec and Mannesmann Tubes, St Saulve (France)</p> <p>2004-07-01</p> <p>A new 12%Cr <span class="hlt">steel</span> integrating good creep properties, fabricability and <span class="hlt">corrosion</span> resistance up to 650 C is being developed. For each step of this development, long term oxidation tests (about 6000 h and 8000 h) were made in pure water vapour in the temperature range 600-650 C. The laboratory and industrial heats were tested in comparison with two 12%Cr <span class="hlt">steels</span> (X20CrMoV12-1), a 9%Cr <span class="hlt">steel</span> (T91) and a fined grain austenitic stainless <span class="hlt">steel</span> (TP347FG). <span class="hlt">Corrosion</span> damage was measured using mass losses obtained after a reducing descaling process. Weight loss and metallographic results confirm the good <span class="hlt">corrosion</span> resistance in steam of the new <span class="hlt">steel</span>, VM12, and show either 2 different <span class="hlt">corrosion</span> mechanisms or the same mechanism but with 2 different spreading rates: for the VM12, one X20 heat and TP347 <span class="hlt">steels</span>, the time required for the whole surface of the samples being covered with <span class="hlt">corrosion</span> products is definitely longer than for the other 9-12% Cr. (orig.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:39068215','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:39068215"><span id="translatedtitle">Water <span class="hlt">corrosion</span> resistance of ODS ferritic-martensitic <span class="hlt">steel</span> tubes</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Oxide dispersion strengthened (ODS) ferritic-martensitic <span class="hlt">steels</span> have superior radiation resistance; it is possible to achieve a service temperature of up to around 973 K because of their superior creep strength. These advantages of ODS <span class="hlt">steels</span> facilities their application to long-life cladding tubes in advanced fast reactor fuel elements. In addition to neutron radiation resistance, sufficient general <span class="hlt">corrosion</span> resistance to maintain the strength of the cladding, and the stress <span class="hlt">corrosion</span> cracking (SCC) resistance for spent-fuel-pool cooling systems and high-temperature oxidation for the fuel-clad chemical interaction (FCCI) of ODS ferritic <span class="hlt">steel</span> are required. Although the addition of Cr to ODS is effective in preventing water <span class="hlt">corrosion</span> and high-temperature oxidation, an excessively high amount of Cr leads to embrittlement due to the formation of a Cr-rich ?' precipitate. The Cr content in 9Cr-ODS martensite and 12Cr-ODS ferrite, the ODS <span class="hlt">steels</span> developed by the Japan Atomic Energy Agency (JAEA), is controlled. In a previous paper, it has been demonstrated that the resistances of 9Cr- and 12Cr-ODS ferritic-martensitic <span class="hlt">steels</span> for high-temperature oxidation are superior to those of conventional 12Cr ferritic <span class="hlt">steel</span>. However, the water <span class="hlt">corrosion</span> data of ODS ferritic-martensitic <span class="hlt">steels</span> are very limited. In this study, a water <span class="hlt">corrosion</span> test was conducted on ODS <span class="hlt">steels</span> in consideration of the spent-fuel-pool cooling condition, and the results were compared with those of conventional austenitic stainless <span class="hlt">steel</span> and ferritic-martensitic stainless <span class="hlt">steel</span>. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://fstroj.uniza.sk/journal-mi/PDF/2011/20-2011.pdf','DOAJ-ART-EN'); return false;" href="http://fstroj.uniza.sk/journal-mi/PDF/2011/20-2011.pdf"><span id="translatedtitle">PITTING <span class="hlt">CORROSION</span> OF STAINLESS <span class="hlt">STEEL</span> AT THE VARIOUS SURFACE TREATMENT</span></a></p> <p><a target="_blank" href="http://www.doaj.org/doaj?func=searchArticles">Directory of Open Access Journals (Sweden)</a></p> <p>Viera Zatkalíková</p> <p>2011-09-01</p> <p>Full Text Available The stainless <span class="hlt">steel</span> surface treatment is very important with regard to its pitting <span class="hlt">corrosion</span> susceptibility. An effect of various types surfacing on pitting <span class="hlt">corrosion</span> resistance of AISI 304stainless <span class="hlt">steel</span> is investigated in this work. The samples of the tested material are turned, blasted, peened, grinded and a half of them are pickled to achieve higher purity of surfaces and better quality of passive film. Eight types of different finished surfaces are tested by electrochemical and immersion tests to determine <span class="hlt">corrosion</span> behaviour in conditions where pitting is evoked by controlled potential and second by solution with high redox potential. By this way the effect of mechanical and chemical surface treatment on the resistance to pitting <span class="hlt">corrosion</span>, character, size and shape of pits are compared in the conditions of different mechanisms of <span class="hlt">corrosion</span> process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ojs.mateng.sk/index.php/Mateng/article/view/20','DOAJ-ART-EN'); return false;" href="http://ojs.mateng.sk/index.php/Mateng/article/view/20"><span id="translatedtitle">PITTING <span class="hlt">CORROSION</span> OF STAINLESS <span class="hlt">STEEL</span> AT THE VARIOUS SURFACE TREATMENT</span></a></p> <p><a target="_blank" href="http://www.doaj.org/doaj?func=searchArticles">Directory of Open Access Journals (Sweden)</a></p> <p>Viera Zatkalíková</p> <p>2012-02-01</p> <p>Full Text Available The stainless <span class="hlt">steel</span> surface treatment is very important with regard to its pitting <span class="hlt">corrosion</span> susceptibility. An effect of various types surfacing on pitting <span class="hlt">corrosion</span> resistance of AISI 304stainless <span class="hlt">steel</span> is investigated in this work. The samples of the tested material are turned, blasted, peened, grinded and a half of them are pickled to achieve higher purity of surfaces and better quality of passive film. Eight types of different finished surfaces are tested by electrochemical and immersion tests to determine <span class="hlt">corrosion</span> behaviour in conditions where pitting is evoked by controlled potential and second by solution with high redox potential. By this way the effect of mechanical and chemical surface treatment on the resistance to pitting <span class="hlt">corrosion</span>, character, size and shape of pits are compared in the conditions of different mechanisms of <span class="hlt">corrosion</span> process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:36014296','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:36014296"><span id="translatedtitle"><span class="hlt">Corrosion</span> of carbon <span class="hlt">steel</span> liners within failed nuclear waste containers</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The <span class="hlt">corrosion</span> of carbon <span class="hlt">steel</span> liners in failed Canadian nuclear waste containers could have a major effect on the redox conditions controlling the subsequent dissolution of the fuel waste form. Consequently, we have been studying the <span class="hlt">corrosion</span> of carbon <span class="hlt">steel</span> in anoxic simulated groundwaters, which could flood a failed container. Voltammetric scans were performed on a rotating ring-disc electrode to quantify the amount, and potential region, of active Fe2+ release. Potentiostatic experiments were performed to monitor <span class="hlt">corrosion</span> product deposit growth rates. Raman spectroscopy and scanning electron microscopy of surface deposits indicated surface composition varied from predominantly siderite (FeCO3) (nodular deposits) in carbonate-dominated waters to magnetite (Fe3O4) (compact deposit of very small crystals) in sulphate-dominated waters. Open circuit measurements accompanied by periodic electrochemical impedance spectroscopy measurements showed that active <span class="hlt">corrosion</span> conditions with the accumulation of a Fe3O4 deposit appear sustainable under natural <span class="hlt">corrosion</span> conditions. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:21054489','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:21054489"><span id="translatedtitle"><span class="hlt">Corrosion</span> of carbon <span class="hlt">steel</span> nuclear waste containers in marine sediment</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The report describes a study of the <span class="hlt">corrosion</span> of carbon <span class="hlt">steel</span> nuclear waste containers in deep ocean sediments, which had the objective of estimating the metals allowance needed to ensure that the containers were not breached by <span class="hlt">corrosion</span> for 1000 years. It is concluded that, under such disposal conditions, carbon <span class="hlt">steel</span> would not be subject to localized <span class="hlt">corrosion</span>. Therefore, the study concentrated on evaluating the rate of general attack. This was done by developing a mechanistically based mathematical model that was formulated on the conservative assumption that the <span class="hlt">corrosion</span> would be under activation control and would not be impeded by the formation of <span class="hlt">corrosion</span> product layers. This model predicted that an allowance of 33 mm would be required for a 1000-year life</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:19016971','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:19016971"><span id="translatedtitle"><span class="hlt">Corrosion</span> of carbon <span class="hlt">steel</span> nuclear waste containers in marine sediment</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The report describes a study of the <span class="hlt">corrosion</span> of carbon <span class="hlt">steel</span> nuclear waste containers in deep ocean sediments, which had the objective of estimating the metal allowance needed to ensure that the containers were not breached by <span class="hlt">corrosion</span> for 1000 years. It was concluded that under such disposal conditions carbon <span class="hlt">steel</span> would not be subject to localised <span class="hlt">corrosion</span> or hydrogen embrittlement, and therefore the study concentrated on evaluating the rate of general attack. This was carried out by developing a mechanistically based mathematical model which was formulated on the conservative assumption that the <span class="hlt">corrosion</span> would be under activation control, and would not be impeded by the formation of <span class="hlt">corrosion</span> product layers. This model predicted that an allowance of 33 mm would be required for a 1000 year life. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:23076415','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:23076415"><span id="translatedtitle">Crevice <span class="hlt">corrosion</span> resistivity assessment of carbon <span class="hlt">steel</span> and stainless alloys</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The disposal facility for radioactive wastes requires long-term integrity. Metal is considering to use as the engineered barrier which constructs the outer walls in such facility, in order to prevent groundwater from percolating into such disposal facility. The present report discusses crevice <span class="hlt">corrosion</span> resistivity assessment of carbon <span class="hlt">steel</span> and stainless alloys. Potential-pH (E-pH) diagram for carbon <span class="hlt">steel</span> is obtained in the environment of water which imitates groundwater in Japan. And the repassivation potential for crevice <span class="hlt">corrosion</span>, ER,CREV, is measured by an electro-chemical test. And natural <span class="hlt">corrosion</span> potential, ESP, and ER,CREV for stainless alloys. Type 304 <span class="hlt">steel</span> and Titanium alloys (ASTM Gr. 1-Ti, Gr, 12-Ti), are measured in the environment of neutral and alkalized water. And usable condition of these materials are discussed. The conclusion of this paper are: 1) In the environment of higher values of pH, carbon <span class="hlt">steel</span> is in the state of passivation. In this state it can occur crevice <span class="hlt">corrosion</span>, at least in the condition of [Cl-]? 10ppm. So, using carbon <span class="hlt">steel</span> is inadequate for coexistence with concrete lining which shows higher pH environment. In neutral pH environment which without concrete, carbon <span class="hlt">steel</span> is in the state of uniform <span class="hlt">corrosion</span>, and can be used by previous consideration of diminishing its thickness by <span class="hlt">corrosion</span>. 2) Usable diagram for crevice <span class="hlt">corrosion</span> of stainless alloys is obtained, which includes [Cl-] concentration and temperature as a parameter. And it can be said that the adequate selection of materials by using this diagram can assure long-term integrity for groundwater <span class="hlt">corrosion</span>. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/doepatents/biblio/868106','SCIGOV-EN'); return false;" href="http://www.osti.gov/doepatents/biblio/868106"><span id="translatedtitle"><span class="hlt">Corrosion</span> <span class="hlt">protection</span> for silver reflectors</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Arendt, Paul N. (Los Alamos, NM); Scott, Marion L. (Los Alamos, NM)</p> <p>1991-12-31</p> <p>A method of <span class="hlt">protecting</span> silver reflectors from damage caused by contact with gaseous substances which are often present in the atmosphere and a silver reflector which is so <span class="hlt">protected</span>. The inventive method comprises at least partially coating a reflector with a metal oxide such as aluminum oxide to a thickness of 15 .ANG. or less.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:44092690','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:44092690"><span id="translatedtitle">Bacterial <span class="hlt">corrosion</span> in marine sediments: influence of cathodic <span class="hlt">protection</span></span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>In order to <span class="hlt">protect</span> offshore structures from marine <span class="hlt">corrosion</span>, cathodic <span class="hlt">protection</span> is widely applied via sacrificial anodes (for example zinc or aluminium) or impressed current. In aerated seawater, <span class="hlt">steel</span> is considered to be <span class="hlt">protected</span> when a potential of -8050 mV/Cu.CuSO4 is achieved. In many cases, however this potential must be lowered, due to the activity of microorganisms and more specially sulfate-reducing bacteria (SRB). SRB are obligate anaerobes using sulphate as electron acceptor with resultant production of sulphide. Some of them are also able to use hydrogen as energy source, causing cathodic depolarization of <span class="hlt">steel</span> surfaces. An experiment was performed to analyze the relation between SRB activity and use of different cathodic potentials applied to mild <span class="hlt">steel</span> samples in marine sediments. Analytical techniques employed included lipid bio-markers and electrochemical methods. Results indicated an evolution of the bacterial community structure both on the <span class="hlt">steel</span> and in the sediment, as a function of time and potential. The results also show that cathodically produced hydrogen promotes the growth of SRB (author)</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:27034366','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:27034366"><span id="translatedtitle"><span class="hlt">Corrosion</span> properties of stainless <span class="hlt">steel</span> coatings made by different methods of thermal spraying</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The <span class="hlt">corrosion</span> <span class="hlt">protection</span> ability of thermally sprayed stainless <span class="hlt">steel</span> coatings in aggressive environments is considerably limited as compared to bulk materials of the same composition. The two main reasons for the decrease in <span class="hlt">corrosion</span> resistance are the porosity in the coatings and the oxidation of elements, particularly chromium, during spraying process. The <span class="hlt">corrosion</span> resistance and structure of stainless <span class="hlt">steel</span> coatings, ANVAL 254 SMO, made by different methods of thermal spraying were evaluated in this work. The coatings were produced by atmospheric plasma spraying (APS), atmospheric plasma spraying using gas shielding around the plasma (APS/S), low pressure plasma spraying (LPPS), detonation gun spraying (DGS) and high velocity oxyfuel spraying (HVOF). Electrochemical methods were used for determining the <span class="hlt">corrosion</span> <span class="hlt">protection</span> ability of coatings in 3.5% NaCl-solution and in sulfur acid solution (pH 3 and 1). The structure and composition of coatings were studied by optical microscopy and scanning electron microscopy/energy dispersive analysator (SEM/EDS). The porosity of the coatings was determined by water impregnation method, optical microscopy and mercury porosimeter. The results showed that the best coating quality can be achieved by LPPS- and HVOF-coatings. Oxidation and porosity restrict the use of APS-coatings in <span class="hlt">corrosive</span> environments. The oxidation can be avoided by using argon gas shield around the plasma flame during spraying. Due to porosity all studied coatings suffered crevice <span class="hlt">corrosion</span> in chloride solution. Despite high Mo-alloying the best coatings reached only the <span class="hlt">corrosion</span> resistance of AISI 316</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://orbit.dtu.dk/ws/files/103681330/Anders_Ole_Stubbegaard_Solgaard_Afhandling..PDF','DEFFRD-EN'); return false;" href="http://orbit.dtu.dk/ws/files/103681330/Anders_Ole_Stubbegaard_Solgaard_Afhandling..PDF"><span id="translatedtitle"><span class="hlt">Corrosion</span> of reinforcement bars in <span class="hlt">steel</span> ibre reinforced concrete structures</span></a></p> <p><a target="_blank" href="http://forskningsbasen.deff.dk/?lang=eng">DEFF Research Database (Denmark)</a></p> <p>Solgaard, Anders Ole Stubbe</p> <p></p> <p>resistivity of concrete, which is known to affect the <span class="hlt">corrosion</span> process of embedded reinforcement. The work concerning the impact of <span class="hlt">steel</span> fibres on initiation and propagation of cracks was linked to <span class="hlt">corrosion</span> initiation and propagation of embedded reinforcement bars via additional studies. Cracks in the...... concrete cover are known to alter the ingress rate of depassivating substances and thereby influence the <span class="hlt">corrosion</span> process. The Ph.D. study covered numerical as well as experimental studies. Electrochemically passive <span class="hlt">steel</span> fibres are electrically isolating thus not changing the electrical resistivity of...... concrete, whereas electrochemically active (depassivated/corroding) <span class="hlt">steel</span> fibres are conducting. The impact of electrochemically active (depassivated/corroding) <span class="hlt">steel</span> fibres on the electrical resistivity of SFRC was studied experimentally and analytically herein. Those studies showed that the addition of...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ljs.academicdirect.org/A14/140_146.htm','DOAJ-ART-EN'); return false;" href="http://ljs.academicdirect.org/A14/140_146.htm"><span id="translatedtitle">Investigation of Fecraly Coating on <span class="hlt">Corrosion</span> Behaviour of Mild <span class="hlt">Steel</span></span></a></p> <p><a target="_blank" href="http://www.doaj.org/doaj?func=searchArticles">Directory of Open Access Journals (Sweden)</a></p> <p>Joseph B. AGBOOLA</p> <p>2009-07-01</p> <p>Full Text Available <span class="hlt">Steel</span> has found wide application in hot rolling equipments in the <span class="hlt">steel</span> industry and the oil rig structures in sea water. These equipments are frequently subjected to <span class="hlt">corrosive</span> and temperature condition which causes severe damage to them, hence the need to develop <span class="hlt">steel</span> suitable to withstand these conditions in terms of surface treatment. This research work investigates the effect of FeCrAlY coating on mild <span class="hlt">steel</span> under high temperature and aggressive environment. Iron based coatings are used due to low cost among other properties such as good <span class="hlt">corrosion</span> resistance, ease of machining and high ductility when compared to hard metals.Thermal spraying of the specimens was carried out using high velocity oxygen fuel (HVOF. <span class="hlt">Corrosion</span> test was carried out on both coated and uncoated samples. All samples were subjected to the same high temperature treatment for oxidation test.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:11551596','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:11551596"><span id="translatedtitle"><span class="hlt">Corrosion</span> in lithium-stainless <span class="hlt">steel</span> thermal-convection systems</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The <span class="hlt">corrosion</span> of types 304L and 316 austenitic stainless <span class="hlt">steel</span> by flowing lithium was studied in thermal-convection loops operated at 500 to 6500C. Both weight and compositional changes were measured on specimens distributed throughout each loop and were combined with metallographic examinations to evaluate the <span class="hlt">corrosion</span> processes. The <span class="hlt">corrosion</span> rate and mass transfer characteristics did not significantly differ between the two austenitic stainless <span class="hlt">steels</span>. Addition of 500 or 1700 wt ppM N to purified lithium did not increase the dissolution rate or change the attack mode of type 316 stainless <span class="hlt">steel</span>. Adding 5 wt % Al to the lithium reduced the weight loss of this <span class="hlt">steel</span> by a factor of 5 relative to a pure lithium-thermal-convection loop</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=doajarticles::d37f7e51a3ea70e5d58f448b2c276f27','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=doajarticles::d37f7e51a3ea70e5d58f448b2c276f27"><span id="translatedtitle">Synthesis and Characterization of Zinc Carboxylates as Aqueous <span class="hlt">Corrosion</span> Inhibitors for Mild <span class="hlt">Steel</span> and 2024, 6061, and 7075 Aluminum Alloys</span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>Volkan Cicek; Mehmet Ozdemir</p> <p>2013-01-01</p> <p>Synthesis and characterization of environmentally friendly metallo-organic <span class="hlt">corrosion</span> inhibitors for <span class="hlt">protection</span> of mild <span class="hlt">steel</span> and certain aluminum alloys are being sought to replace carcinogenic hexavalent chromium based <span class="hlt">corrosion</span> inhibitors. Given the toxicity and carcinogenicity of chromates, the purpose of this study is not just synthesizing any efficient <span class="hlt">corrosion</span> inhibitors for certain alloys of certain metals to be applied in different environments, but also to find environmentally frien...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=doajarticles::ec2cef7c137065f00bca43c0750e0353','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=doajarticles::ec2cef7c137065f00bca43c0750e0353"><span id="translatedtitle">Synthesis and Characterization of Benzilate Esters as Aqueous <span class="hlt">Corrosion</span> Inhibitors for Mild <span class="hlt">Steel</span> and 2024, 6061, and 7075 Aluminum Alloys</span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>Volkan Cicek; Mehmet Ozdemir</p> <p>2013-01-01</p> <p>In this investigation, synthesis and characterization of environmentally friendly metallo-organic <span class="hlt">corrosion</span> inhibitors for <span class="hlt">protection</span> of mild <span class="hlt">steel</span> and certain aluminum alloys are being sought to replace hexavalent chromium based <span class="hlt">corrosion</span> inhibitors. For this reason, several <span class="hlt">corrosion</span> inhibiting species such as benzilic acid and metal oxyanions were combined in a single compound with the general formula, (M)x(benzilicacid)y(M?aOb)z. First group of such compounds were synthesized in a similar...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26831689','SCIGOV-EN'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26831689"><span id="translatedtitle">Formation of Surface <span class="hlt">Corrosion</span>-Resistant Nanocrystalline Structures on <span class="hlt">Steel</span>.</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Nykyforchyn, Hryhoriy; Kyryliv, Volodymyr; Maksymiv, Olha; Slobodyan, Zvenomyra; Tsyrulnyk, Oleksandr</p> <p>2016-12-01</p> <p>Engineering materials with nanocrystalline structure could be exploited under simultaneous action of mechanical loading and <span class="hlt">corrosion</span> environments; therefore, their <span class="hlt">corrosion</span> resistance is important. Surface nanocrystalline structure was generated on middle carbon <span class="hlt">steels</span> by severe plastic deformation using the method of mechanical pulse friction treatment. This treatment additionally includes high temperature phase transformation and alloying. Using a complex of the <span class="hlt">corrosive</span>, electrochemical and physical investigations, it was established that nanocrystalline structures can be characterized by lower or increased <span class="hlt">corrosion</span> resistance in comparison with the reference material. It is caused by the action of two confronting factors: arising energy level and anticorrosive alloying of the surface layer. PMID:26831689</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9555E..10H','SCIGOV-EN'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9555E..10H"><span id="translatedtitle">Polarization-based optical fiber sensor of <span class="hlt">steel</span> <span class="hlt">corrosion</span></span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Hu, Wenbin; Zhu, Cheng; Zheng, Xing; Gao, Min; Guo, Donglai; Chen, Wei</p> <p>2015-08-01</p> <p>Metal-coated D-shape optical fiber is serving as a polarizer by using its attenuation difference for two orthogonal fundamental modes. This paper presents a novel <span class="hlt">corrosion</span> sensor, based on an iron-coated optical fiber polarizer. The sensor is fabricated by sputtering a Fe-C film on a side-polished single mode fiber. The extinction ratio and the optical power loss are varying during the <span class="hlt">corrosion</span> process when the iron-coated sensor is exposed to a <span class="hlt">corrosive</span> environment. The proposed sensor provides a new approach for monitoring the early-age <span class="hlt">corrosion</span> of <span class="hlt">steel</span> structures by tracing the variation of polarization characteristics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ias.ac.in/describe/article/boms/026/03/0307-0310','GOOGLE-IAS-EN'); return false;" href="http://www.ias.ac.in/describe/article/boms/026/03/0307-0310"><span id="translatedtitle">Study on <span class="hlt">corrosion</span> simulation device for marine structural <span class="hlt">steel</span></span></a></p> <p><a target="_blank" href="http://www.ias.ac.in/">Indian Academy of Sciences (India)</a></p> <p>Hou Baorong; Xiang Bin</p> <p>2003-04-01</p> <p>A <span class="hlt">corrosion</span> simulation device was studied using offshore long scale hanging specimens. An Ni–Cu–P <span class="hlt">steel</span> specimen was studied by analysing its <span class="hlt">corrosion</span> products and <span class="hlt">corrosion</span> types. The appearance of the samples and the surface of the metallic substrate after the removal of the rust layer produced by these two methods were observed and compared after 470 days of exposure. The phase structure of the <span class="hlt">corrosion</span> products under different marine environments were analysed and compared. It further indicated good correlation between the electrically connected hanging specimen method and the long scale hanging specimen method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/doepatents/biblio/644401','SCIGOV-EN'); return false;" href="http://www.osti.gov/doepatents/biblio/644401"><span id="translatedtitle"><span class="hlt">Corrosion</span> <span class="hlt">protective</span> coating for metallic materials</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Buchheit, R.G.; Martinez, M.A.</p> <p>1998-05-26</p> <p><span class="hlt">Corrosion</span> <span class="hlt">protective</span> coatings for metallic materials, particularly aluminum and aluminum alloys, produced with simple, low-cost equipment and materials other than toxic metals or metal salts, or metal cyanides is disclosed. The metallic material is cleaned, degreased, and deoxidized, the surface is converted to a substantially alkaline condition, and the surface is chemically sealed with inorganic metal compounds. 1 fig.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:28024397','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:28024397"><span id="translatedtitle">Evaluation of stainless <span class="hlt">steels</span> for their resistance to intergranular <span class="hlt">corrosion</span></span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Austenitic stainless <span class="hlt">steels</span> are being considered as structural materials for first wall/blanket systems in the international thermonuclear reactor (ITER). The uniform <span class="hlt">corrosion</span> of stainless <span class="hlt">steels</span> in water is well known and is not a critical issue limiting its application for the ITER design. The sensitivity of austenitic <span class="hlt">steels</span> to intergranular <span class="hlt">corrosion</span> (IGC) can be estimated rather accurately by means of calculation methods, considering structure and chemical composition of <span class="hlt">steel</span>. There is a maximum permissible carbon content level, at which sensitization of stainless <span class="hlt">steel</span> is eliminated: K=Creff-?Ceff, where ?-thermodynamic coefficient, Creff-effective chromium content (regarding molybdenum influence) and Ceff-effective carbon content (taking into account nickel and stabilizing elements). <span class="hlt">Corrosion</span> tests for 16Cr11Ni3MoTi, 316L and 316LN <span class="hlt">steel</span> specimens, irradiated up to 2 x 1022 n/cm2 fluence have proved the effectiveness of this calculation technique for determination of austenitic <span class="hlt">steels</span> tendency to IGC. This method is directly applicable in austenitic stainless <span class="hlt">steel</span> production and enables one to exclude complicated experiments on determination of stainless <span class="hlt">steel</span> susceptibility to IGC. (orig.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.doiserbia.nb.rs/img/doi/0367-598X/2011/0367-598X1000069E.pdf','DOAJ-ART-EN'); return false;" href="http://www.doiserbia.nb.rs/img/doi/0367-598X/2011/0367-598X1000069E.pdf"><span id="translatedtitle">Electrochemical synthesis and <span class="hlt">corrosion</span> behavior of thin polyaniline film on mild <span class="hlt">steel</span>, copper and aluminum</span></a></p> <p><a target="_blank" href="http://www.doaj.org/doaj?func=searchArticles">Directory of Open Access Journals (Sweden)</a></p> <p>Elkais Ali Ramadan</p> <p>2011-01-01</p> <p>Full Text Available The electrochemical synthesis of polyaniline (PANI on mild <span class="hlt">steel</span>, aluminum and copper from the sodium benzoate solutions has been investigated. It has been shown that thin, highly adherent, polyaniline films on the investigated metals could be obtained by anodic oxidation with current densities in the range of 0.5 and 1.5 mA cm-2. The <span class="hlt">corrosion</span> behavior of mild <span class="hlt">steel</span>, aluminum and copper with polyaniline coating in 0.5 mol dm3 NaCl (pH 3 solutions, has been investigated by polarization technique. The <span class="hlt">corrosion</span> current densities, porosity and <span class="hlt">protection</span> efficiency was determined. It has been shown that polyaniline coating provided <span class="hlt">corrosion</span> <span class="hlt">protection</span> of all mentioned metals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008ApSS..254.5569A','SCIGOV-EN'); return false;" href="http://adsabs.harvard.edu/abs/2008ApSS..254.5569A"><span id="translatedtitle">An electroactive co-polymer as <span class="hlt">corrosion</span> inhibitor for <span class="hlt">steel</span> in sulphuric acid medium</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Achary, Ganesha; Naik, Y. Arthoba; Kumar, S. Vijay; Venkatesha, T. V.; Sherigara, B. S.</p> <p>2008-06-01</p> <p>The <span class="hlt">corrosion</span> behavior of mild <span class="hlt">steel</span> in sulphuric acid solution containing various concentrations of a co-polymer formed between maleic anhydride and N-vinyl-2-pyrrolidone (VPMA) was investigated using weight-loss, polarization and electrochemical impedance techniques. The polymer acts as an effective <span class="hlt">corrosion</span> inhibitor for <span class="hlt">steel</span> in sulphuric acid medium. The inhibition process is attributed to the formation of an adsorbed film of co-polymer on the metal surface which <span class="hlt">protects</span> the metal against <span class="hlt">corrosion</span>. Scanning electron microscopy (SEM) studies of the metal surfaces confirmed the existence of an adsorbed film. The adsorption followed the Langmuir isotherm. The <span class="hlt">protection</span> efficiency increased with increase in inhibitor concentration and decreased with increase in temperature and acid concentration. The thermodynamic functions of the adsorption and dissolution processes were evaluated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:40030150','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:40030150"><span id="translatedtitle">An electroactive co-polymer as <span class="hlt">corrosion</span> inhibitor for <span class="hlt">steel</span> in sulphuric acid medium</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The <span class="hlt">corrosion</span> behavior of mild <span class="hlt">steel</span> in sulphuric acid solution containing various concentrations of a co-polymer formed between maleic anhydride and N-vinyl-2-pyrrolidone (VPMA) was investigated using weight-loss, polarization and electrochemical impedance techniques. The polymer acts as an effective <span class="hlt">corrosion</span> inhibitor for <span class="hlt">steel</span> in sulphuric acid medium. The inhibition process is attributed to the formation of an adsorbed film of co-polymer on the metal surface which <span class="hlt">protects</span> the metal against <span class="hlt">corrosion</span>. Scanning electron microscopy (SEM) studies of the metal surfaces confirmed the existence of an adsorbed film. The adsorption followed the Langmuir isotherm. The <span class="hlt">protection</span> efficiency increased with increase in inhibitor concentration and decreased with increase in temperature and acid concentration. The thermodynamic functions of the adsorption and dissolution processes were evaluated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:19093888','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:19093888"><span id="translatedtitle"><span class="hlt">Corrosion</span> and hydrogen permeation of A216 Grade WCA <span class="hlt">steel</span> in hydrothermal magnesium-containing brines</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p><span class="hlt">Corrosion</span> rates determined at 1 month in 150/degree/C brine increased with magnesium concentration. The structure of the <span class="hlt">corrosion</span> product, as determined by x-ray diffraction, depended upon the magnesium concentration. In brines with less than 10,000 ppM magnesium, the primary <span class="hlt">corrosion</span> product had a spinel structure characteristic of magnetite or magnesioferrite. In brines containing magnesium concentrations greater than 20,000 ppM, the primary <span class="hlt">corrosion</span> product had the amakinite structure characteristic of a complex iron-magnesium hydroxide. The high <span class="hlt">corrosion</span> rates observed in brines containing high magnesium concentrations suggest that the <span class="hlt">corrosion</span> products having the amakinite structure is less <span class="hlt">protective</span> than <span class="hlt">corrosion</span> products having the spinel structure. <span class="hlt">Corrosion</span> rates in high-magnesium (inclusion) brine determined over a 6-month test duration were essentially constant. Hydrogen permeation rates observed in exposing mild <span class="hlt">steel</span> to high-Mg/sup 2/plus// brine at 150/degree/C could be potentially damaging to a mild <span class="hlt">steel</span> waste package container. The rate of hydrogen permeation was proportional to the brine flow rate in the autoclave. Thiourea additions to the brine increased the hydrogen permeation rate; sulfate and bromide ion additions did not. The maximum gaseous hydrogen pressure attainable is not known (based on 3Fe /plus/ 4H2O /plus/ Fe(sub 3)O /plus/ 4H2, would be /approximately/900 atmospheres), and the dependence of permeation rate on temperature is not known. 8 refs., 13 figs., 3 tabs</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2013-09-27/pdf/2013-23636.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2013-09-27/pdf/2013-23636.pdf"><span id="translatedtitle">78 FR 59651 - Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From the Republic of Korea: Notice of...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2013-09-27</p> <p>...A-580-816] Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...duty order on certain <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products...2\\ See Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2012-05-30/pdf/2012-13078.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2012-05-30/pdf/2012-13078.pdf"><span id="translatedtitle">77 FR 31877 - <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From Germany and Korea; Scheduling of Full Five...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2012-05-30</p> <p>...Third Review)] <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...countervailing duty order on <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products from...antidumping duty orders on <span class="hlt">corrosion</span>- resistant carbon <span class="hlt">steel</span> flat products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2011-09-06/pdf/2011-22730.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2011-09-06/pdf/2011-22730.pdf"><span id="translatedtitle">76 FR 55004 - Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From the Republic of Korea: Preliminary...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2011-09-06</p> <p>...A-580-816] Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...antidumping order on <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products (CORE...Products and Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2013-03-29/pdf/2013-07402.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2013-03-29/pdf/2013-07402.pdf"><span id="translatedtitle">78 FR 19210 - <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From the Republic of Korea: Final Results of...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2013-03-29</p> <p>...Administration [C-580-818] <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...duty (CVD) order on <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products from...1\\ See <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2011-01-25/pdf/2011-1393.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2011-01-25/pdf/2011-1393.pdf"><span id="translatedtitle">76 FR 4291 - <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From the Republic of Korea: Partial Rescission of...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2011-01-25</p> <p>...Administration [C-580-818] <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...countervailing duty order on <span class="hlt">corrosion</span>- resistant carbon <span class="hlt">steel</span> flat products from...countervailing duty order on <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2010-09-14/pdf/2010-22887.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2010-09-14/pdf/2010-22887.pdf"><span id="translatedtitle">75 FR 55769 - Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From the Republic of Korea: Notice of...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2010-09-14</p> <p>...A-580-816] Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...antidumping order on <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products (CORE...Products and Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2012-09-06/pdf/2012-21993.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2012-09-06/pdf/2012-21993.pdf"><span id="translatedtitle">77 FR 54891 - Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products from the Republic of Korea: Preliminary...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2012-09-06</p> <p>...A-580-816] Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products from...antidumping order on <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products (CORE...2012. See Certain <span class="hlt">Corrosion</span>- Resistant Carbon <span class="hlt">Steel</span> Flat Products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2011-11-09/pdf/2011-29056.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2011-11-09/pdf/2011-29056.pdf"><span id="translatedtitle">76 FR 69703 - <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From the Republic of Korea: Notice of Extension of...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2011-11-09</p> <p>...Administration [A-580-816] <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...antidumping duty order on <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products from...review. See Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2010-12-13/pdf/2010-31217.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2010-12-13/pdf/2010-31217.pdf"><span id="translatedtitle">75 FR 77615 - <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From the Republic of Korea: Notice of Extension of...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2010-12-13</p> <p>...Administration [A-580-816] <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...antidumping duty order on <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products from...review. See Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2012-01-04/pdf/2011-33770.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2012-01-04/pdf/2011-33770.pdf"><span id="translatedtitle">77 FR 301 - <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From Germany and Korea: Institution of Five-Year...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2012-01-04</p> <p>...Third Review)] <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...Countervailing Duty Order on <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...Antidumping Duty Orders on <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2011-12-14/pdf/2011-32092.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2011-12-14/pdf/2011-32092.pdf"><span id="translatedtitle">76 FR 77775 - <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products from the Republic of Korea: Extension of Time...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2011-12-14</p> <p>...Administration [C-580-818] <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products from...countervailing duty order on <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products from...December 31, 2009. See <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2013-09-27/pdf/2013-23643.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2013-09-27/pdf/2013-23643.pdf"><span id="translatedtitle">78 FR 59652 - Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From the Republic of Korea: Notice of...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2013-09-27</p> <p>...A-580-816] Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...duty order on certain <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products...2\\ See Certain <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2013-09-09/pdf/2013-21890.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2013-09-09/pdf/2013-21890.pdf"><span id="translatedtitle">78 FR 55057 - <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products from the Republic of Korea: Preliminary Results of...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2013-09-09</p> <p>...Administration [A-580-816] <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products from...antidumping duty order on <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products (CORE...effective this date. See <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.gpo.gov:80/fdsys/pkg/FR-2012-04-23/pdf/2012-9665.pdf','SCIGOV-EN'); return false;" href="http://www.gpo.gov:80/fdsys/pkg/FR-2012-04-23/pdf/2012-9665.pdf"><span id="translatedtitle">77 FR 24221 - <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From Germany and Korea; Notice of Commission...</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2012-04-23</p> <p>...Third Review)] <span class="hlt">Corrosion</span>-Resistant Carbon <span class="hlt">Steel</span> Flat Products From...countervailing duty order on <span class="hlt">corrosion</span>-resistant carbon <span class="hlt">steel</span> flat products from...antidumping duty orders on <span class="hlt">corrosion</span>- resistant carbon <span class="hlt">steel</span> flat products...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:19059372','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:19059372"><span id="translatedtitle">Stress <span class="hlt">corrosion</span> cracking <span class="hlt">protection</span> device</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Purpose: To reduce dissolved oxygen at a reduced cost and simply thereby prevent stress <span class="hlt">corrosion</span> cracking. Constitution: Taking notice of the fact that dissolved oxygen concentration is reduced in reactor water in contact with organic materials irradiated with radioactive rays such as ?-rays, organic materials such as polyethylenes are disposed to the inside of pipeways in reactor clean-up systems and radioactive rays are irradiated to them. Thus, reactor water can be brought into contact with organic materials, by which dissolved oxygen is caught by organic materials under the action of the radioactive rays to reduce the dissolved oxygen concentration. Further, if the organic materials are disposed to the inside of the pipeways connecting the heat exchanger and the desalter of the clean-up system, since the temperature of the reactor water is relatively low and the flow rate is not so high in this portion, dissolved oxygen can be removed stably and efficiently. (Kawakami, Y.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=109922','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=109922"><span id="translatedtitle">Stable non-<span class="hlt">protective</span> films and atmospheric <span class="hlt">corrosion</span></span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Payer, J.H.; Ball, G.R.; Rickett, B.I.; Kim, H.S. [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Materials Science and Engineering</p> <p>1995-10-01</p> <p>In order for a <span class="hlt">corrosion</span> process to proceed beyond a few monolayers, the transport of reactants through the <span class="hlt">corrosion</span> product layer is necessary. The formation of a stable non-<span class="hlt">protective</span> film is required for <span class="hlt">corrosion</span> to continue beyond initial stages. High rates of ionic transport through the non-<span class="hlt">protective</span> film on the metal surface supply reactants to the <span class="hlt">corrosion</span> reaction interface and allow <span class="hlt">corrosion</span> to continue beyond surface coverage. In this paper, the processes relevant to film stability in atmospheric <span class="hlt">corrosion</span> are identified and discussed. Several systems currently under study in the research group will be discussed in the context of non-<span class="hlt">protective</span> films and <span class="hlt">corrosion</span> reactant transport.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://jfas.info/index.php/jfas/article/view/20/25','DOAJ-ART-EN'); return false;" href="http://jfas.info/index.php/jfas/article/view/20/25"><span id="translatedtitle">ANTICORROSION POTENTIAL OF HYDRALAZINE FOR <span class="hlt">CORROSION</span> OF MILD <span class="hlt">STEEL</span> IN 1M HYDROCHLORIC ACID SOLUTION</span></a></p> <p><a target="_blank" href="http://www.doaj.org/doaj?func=searchArticles">Directory of Open Access Journals (Sweden)</a></p> <p>B. M. Prasanna</p> <p>2015-05-01</p> <p>Full Text Available Anticorrosion potential of mild <span class="hlt">steel</span> by Hydralazine as <span class="hlt">corrosion</span> inhibitor for mild <span class="hlt">steel</span> in 1M hydrochloric acid was investigated by chemical and electrochemical measurements at 303-333 K temperature. The maximum inhibition efficiency of inhibitor by Weight loss method is around 90%, Tafel polarization method is around 85%; electrochemical impedance spectroscopy measurement around 90% at 1250 ppm of Hydralazine in. The result shows that the inhibition efficiency increases with I 1M hydrochloric acid. Hydralazine acts as a mixed type inhibitor which inhibits the <span class="hlt">corrosion</span> of mild <span class="hlt">steel</span> due to the adsorption on metal surface. This adsorption system obeys the Langmuir adsorption isotherm.Activation parameters explains the effect of temperature with inhibition efficiency of inhibitor molecule.SEM images of inhibited mild <span class="hlt">steel</span> strips shows a formation of passive <span class="hlt">protective</span> film over the surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=21395150','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=21395150"><span id="translatedtitle">Investigation on <span class="hlt">corrosion</span> of titanium/<span class="hlt">steel</span> brazed joint</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Elrefaey, A.; Wojarski, L.; Tillmann, W. [TU Dortmund (Germany). Lehrstuhl fuer Werkstofftechnologie</p> <p>2010-11-15</p> <p>Furnace vacuum brazing has been employed to join commercially pure titanium alloy and low carbon <span class="hlt">steel</span> using a silver-based filler metal with a composition of Ag-Cu34-Ti2 (wt%). Three different brazing temperatures (850 C, 880 C, 930 C) and two holding times (5 and 15 min) were applied and evaluated. The <span class="hlt">corrosion</span> behavior of the joints in 0.1 M sulfuric acid was investigated using immersion and electrochemical tests. Measurements of <span class="hlt">corrosion</span> potential, <span class="hlt">corrosion</span> current density, <span class="hlt">corrosion</span> rate, polarization resistance, weight loss, and morphology of <span class="hlt">corrosion</span> attack were used in this study. The results indicated that a severe <span class="hlt">corrosion</span> attack at the interfacial area of the <span class="hlt">steel</span> side took place. Despite the difference in <span class="hlt">corrosion</span> rate values obtained by electrochemical and weight loss measurements, the trend of the results was identical to a large extent. The <span class="hlt">corrosion</span> resistance of the joint showed a general tendency to increase with an increasing brazing temperature and holding time. Therefore, the joints produced at a temperature of 930 C and a holding time of 15 min produced the best result concerning the <span class="hlt">corrosion</span> behavior. (orig.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:41014525','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:41014525"><span id="translatedtitle">Environmental factors affecting the <span class="hlt">corrosion</span> behavior of reinforcing <span class="hlt">steel</span> III. Measurement of pitting <span class="hlt">corrosion</span> currents of <span class="hlt">steel</span> in Ca(OH)2 solutions under natural <span class="hlt">corrosion</span> conditions</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Using a simple electrolytic cell, the pitting <span class="hlt">corrosion</span> current of reinforcing <span class="hlt">steel</span> is measured in Ca(OH)2 solutions in presence of chloride and sulfate as aggressive ions. Pitting <span class="hlt">corrosion</span> current starts to flow after an induction period which depends on the concentration of both the aggressive and the passivating anions. The pitting <span class="hlt">corrosion</span> current densities reach steady-state values which depend also on the type and concentration of the <span class="hlt">corrosive</span> and passivating anions. The <span class="hlt">corrosive</span> action of the aggressive species decreased in the order: SO42- > Cl-. <span class="hlt">Corrosion</span> of the <span class="hlt">steel</span> is found to be governed by a single electron transfer reaction. Raising the temperature decreases the induction period associated with pit initiation and increases the <span class="hlt">corrosion</span> current associated with pit propagation. From Arrhenius plots, the activation energies for both pit initiation and pit propagation in presence of chloride and sulfate ions are calculated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:44012538','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:44012538"><span id="translatedtitle">Poly(o-phenylenediamine) as an inhibitor of mild <span class="hlt">steel</span> <span class="hlt">corrosion</span> in HCl solution</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The inhibition properties of the electro-prepared P(o-phenylenediamine), P(oPD), on the <span class="hlt">corrosion</span> rate of mild <span class="hlt">steel</span> (MS) in HCl solutions have been investigated under different experimental conditions using weight loss and potentiodynamic polarization techniques. The data obtained from the two techniques are comparable and showed that the presence of P(oPD) in the acid solutions suppresses the <span class="hlt">corrosion</span> rate of MS indicating that the polymer acts as <span class="hlt">corrosion</span> inhibitor. The inhibition efficiency (IE%) of the polymer enhances with increasing its concentration and decreases with an increase in temperature. The inhibition occurs through adsorption and formation of barrier film on the metal surface which separates the metal from direct contact with the <span class="hlt">corrosive</span> medium and hence <span class="hlt">protects</span> the metal against the <span class="hlt">corrosion</span>. Langmuir isotherm fits well with the experimental data. Thermodynamic parameters for both dissolution and adsorption processes were determined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=22052574','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=22052574"><span id="translatedtitle">Poly(o-phenylenediamine) as an inhibitor of mild <span class="hlt">steel</span> <span class="hlt">corrosion</span> in HCl solution</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Abd El Rehim, S.S. [Chemistry Department, Faculty of Science, Ain Shams University, Cairo (Egypt); Sayyah, S.M., E-mail: smsayyah@hotmail.com [Polymer Research Laboratory, Chemistry Department, Faculty of Science, Beni-Suef University, 62514 Beni-Suef (Egypt); El-Deeb, M.M.; Kamal, S.M.; Azooz, R.E. [Polymer Research Laboratory, Chemistry Department, Faculty of Science, Beni-Suef University, 62514 Beni-Suef (Egypt)</p> <p>2010-09-01</p> <p>The inhibition properties of the electro-prepared P(o-phenylenediamine), P(oPD), on the <span class="hlt">corrosion</span> rate of mild <span class="hlt">steel</span> (MS) in HCl solutions have been investigated under different experimental conditions using weight loss and potentiodynamic polarization techniques. The data obtained from the two techniques are comparable and showed that the presence of P(oPD) in the acid solutions suppresses the <span class="hlt">corrosion</span> rate of MS indicating that the polymer acts as <span class="hlt">corrosion</span> inhibitor. The inhibition efficiency (IE%) of the polymer enhances with increasing its concentration and decreases with an increase in temperature. The inhibition occurs through adsorption and formation of barrier film on the metal surface which separates the metal from direct contact with the <span class="hlt">corrosive</span> medium and hence <span class="hlt">protects</span> the metal against the <span class="hlt">corrosion</span>. Langmuir isotherm fits well with the experimental data. Thermodynamic parameters for both dissolution and adsorption processes were determined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:38045038','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:38045038"><span id="translatedtitle"><span class="hlt">Corrosion</span> <span class="hlt">protection</span> and finishing of automobiles</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>finishing of automobiles is an important aspect. There have been considerable reductions of weight in automobiles by the use of composites components replacing heavy metallic components. Fenders previously based on metal have been replaced with plastic and painted with the same colour shade as of the metallic body, this has eps for proper adhesion of the paints on the plastic fender to avoid chipping off the paint form it. This paper discusses the necessary processes required for finishing of an automobile along with the <span class="hlt">corrosion</span> <span class="hlt">protection</span> measures. Automobiles contains a variety of engineering materials, engine main body fuel tanks connecting rods heat radiators and other mechanical parts are made from different types of engineering alloys having varying chemical compositions. Other parts like dashboard, front panel and other are made from composites. The main body made from cold roll ed <span class="hlt">steel</span> having various contours 'c' it due to the different designs is the potential site for <span class="hlt">corrosion</span> attack, The main body is exposed to the hostile environment through out its life period. An automobile is given a particular finish with a view to counter the hostile environments as they are not limited for plying in a limiting conditions and are taken to different weather conditions in one day thus facing severe stresses and strain. Thus it is essential that an automobile before rolling 'out of the assembly line should properly <span class="hlt">corrosion</span> resistant and aesthetically pleasant also. Finishing for automobiles being very specialized, the main requirement being maximum durability with minimum numbers of coats baked, at the fastest possible schedule. High gloss and range of good eye catching colours being important to increase sales appeal. In the near past the car finishes were based on alkyd-amino resins baking materials and force drying lacquers, which have excellent appearance originally and maintain it on aging. The finishing system for the synthetic baking type may consist of one primer coat and a double finish coat. The two finishing coats are applied one immediately after the other, and both are baked simultaneously. An alternate system is to apply a red iron oxide epoxy primer followed by a gray epoxy primer and to bake the two coats at 200 degree C for about 35 minutes. The dry film thickness is about is about 1.5 mils. This coating is wet sanded, washed, and dried then top-coated with a double (wet-on-wet) coat of alkyd-amino resin enamel. The enamel is baked at 120 degree C for about 35 minutes. The lacquer system consists of one prime coat followed by several coats of lacquer finish. Number of coats depending on the price range of the car. All the efforts are made to make the metal surface as smooth as possible and free from rough places due to spot wielding and filing. This means a minimum of sanding on the primer, thus saving in labour cost but also makes possible less pigment in the primer resulting in better hold-out of the finish. However, the primer must be hard enough to sand easily, because rubbery primers tare slow sanding and tend to show scratch marks from the sand paper. All metal surfaces are given a passivating treatment before application of the primer. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.scielo.oces.mctes.pt/scielo.php?script=sci_arttext&pid=S0872-19042011000400004','DOAJ-ART-EN'); return false;" href="http://www.scielo.oces.mctes.pt/scielo.php?script=sci_arttext&pid=S0872-19042011000400004"><span id="translatedtitle">Ranitidine Drugs as Non-Toxic <span class="hlt">Corrosion</span> Inhibitors for Mild <span class="hlt">Steel</span> in Hydrochloric Acid Medium</span></a></p> <p><a target="_blank" href="http://www.doaj.org/doaj?func=searchArticles">Directory of Open Access Journals (Sweden)</a></p> <p>R.S. Abdel Hameed</p> <p>2011-01-01</p> <p>Full Text Available Expired ranitidine was tested as a <span class="hlt">corrosion</span> inhibitor for mild <span class="hlt">steel</span> in 1 M HCl using different techniques: weight loss, potentiodynamic polarization, open circuit potential and electrochemical impedance spectroscopy. The polarization resistance (Rp value increased with increase in the concentration of the inhibitor. Results obtained revealed that ranitidine performed excellently as a <span class="hlt">corrosion</span> inhibitor for mild <span class="hlt">steel</span> in this medium at 303 K. The <span class="hlt">protection</span> efficiency increased with increasing inhibitor concentration. The maximum <span class="hlt">protection</span> efficiency of 90% has been obtained at 400 ppm. On the other hand, the efficiency decreases with increasing temperature. The adsorption of the inhibitor on the mild <span class="hlt">steel</span> surface followed Langmuir adsorption isotherm model. The activation and thermodynamic parameters of dissolution and adsorption were calculated and discussed. The negative value of ?Gads (-40 kJ mol-1 indicates spontaneous chemical adsorption. Results obtained from polarization, EIS and weight loss measurements are in good agreement with each other.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.scielo.gpeari.mctes.pt/scielo.php?script=sci_arttext&pid=S0872-19042011000400004&lang=en','SCIELO-EN'); return false;" href="http://www.scielo.gpeari.mctes.pt/scielo.php?script=sci_arttext&pid=S0872-19042011000400004&lang=en"><span id="translatedtitle">/ Ranitidine Drugs as Non-Toxic <span class="hlt">Corrosion</span> Inhibitors for Mild <span class="hlt">Steel</span> in Hydrochloric Acid Medium</span></a></p> <p><a target="_blank" href="http://www.scielo.org/php/index.php?lang=en">Scientific Electronic Library Online (English)</a></p> <p>R.S., Abdel Hameed.</p> <p></p> <p>Full Text Available Expired ranitidine was tested as a <span class="hlt">corrosion</span> inhibitor for mild <span class="hlt">steel</span> in 1 M HCl using different techniques: weight loss, potentiodynamic polarization, open circuit potential and electrochemical impedance spectroscopy. The polarization resistance (Rp) value increased with increase in the concentrati [...] on of the inhibitor. Results obtained revealed that ranitidine performed excellently as a <span class="hlt">corrosion</span> inhibitor for mild <span class="hlt">steel</span> in this medium at 303 K. The <span class="hlt">protection</span> efficiency increased with increasing inhibitor concentration. The maximum <span class="hlt">protection</span> efficiency of 90% has been obtained at 400 ppm. On the other hand, the efficiency decreases with increasing temperature. The adsorption of the inhibitor on the mild <span class="hlt">steel</span> surface followed Langmuir adsorption isotherm model. The activation and thermodynamic parameters of dissolution and adsorption were calculated and discussed. The negative value of ?Gads (-40 kJ mol-1) indicates spontaneous chemical adsorption. Results obtained from polarization, EIS and weight loss measurements are in good agreement with each other.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=21527292','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=21527292"><span id="translatedtitle">Materials <span class="hlt">corrosion</span> and <span class="hlt">protection</span> at high temperatures; <span class="hlt">Corrosion</span> et <span class="hlt">protection</span> des materiaux a haute temperature</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Balbaud, F.; Desgranges, Clara; Martinelli, Laure; Rouillard, Fabien [CEA-Saclay, DEN, DPC, SCCME, Laboratoire d' Etude de la Corrosion Non Aqueuse, 91191 Gif-sur-Yvette Cedex (France); Duhamel, Cecile [Mines ParisTech, Centre des materiaux UMR-CNRS 7633, BP 87, 91003 Evry Cedex (France); Marchetti, Loic; Perrin, Stephane [CEA, Laboratoire d' Etude de la Corrosion Aqueuse (France); Molins, Regine [Mines ParisTech, Direction de la Recherche, 60 Bvd Saint Michel, 75272 Paris Cedex 06 (France); Chevalier, S.; Heintz, O. [Laboratoire interdisciplinaire Carnot de Bourgogne, UMR 5209 CNRS, Univ. de Bourgogne, Dijon (France); David, N.; Fiorani, J.M.; Vilasi, M. [Institut Jean Lamour, UMR 7198, Univ. Henri Poincare Nancy-1 - CNRS, 54506 Vandoeuvre-les-Nancy (France); Wouters, Y.; Galerie, A. [SIMAP UMR CNRS 5266, Grenoble-INP/UJF, 1130 rue de la Piscine BP 75, 38402 Saint-Martin-d' Heres Cedex (France); Mangelinck, D. [IM2NP, UMR6242, CNRS, Univ. Paul Cezanne, Case 142, Faculte de Saint Jerome, 13397 Marseille Cedex 20 (France); Viguier, B.; Monceau, D. [Univ. de Toulouse, Institut Carnot CIRIMAT, INP-ENSIACET, 4 allee Emile Monso, BP 44362, 31030 Toulouse Cedex 4 (France); Soustelle, M. [Ecole nationale superieure des mines, Saint Etienne (France); Pijolat, M. [Centre Spin, Ecole des mines de Saint Etienne (France); Favergeon, J.; Brancherie, D.; Moulin, G.; Dawi, K. [Laboratoire Roberval, UTC (France); Wolski, K.; Barnier, V. [Centre SMS, EMSE, UMR 5146, LCG, Univ. de Lyon, 158 Cours Fauriel, 42023 Saint Etienne (France); Rebillat, F. [LCTS, Univ. de Bordeaux (France); Lavigne, O. [Onera, Dep. Materiaux et Structures Metalliques, BP 72, 29 av. de la Division Leclerc, 92322 Chatillon (France); Brossard, J.M. [Dep. energetique et procedes, Veolia Environnement Recherche et Innovation, Limay (France); Ropital, F. [IFP Energies Nouvelles, BP 3, 69360 Solaize (France); Mougin, J. [CEA-Liten, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)</p> <p>2011-07-01</p> <p>This book was made from the lectures given in 2010 at the thematic school on 'materials <span class="hlt">corrosion</span> and <span class="hlt">protection</span> at high temperatures'. It gathers the contributions from scientists and engineers coming from various communities and presents a state-of-the-art of the scientific and technological developments concerning the behaviour of materials at high temperature, in aggressive environments and in various domains (aerospace, nuclear, energy valorization, and chemical industries). It supplies pedagogical tools to grasp high temperature <span class="hlt">corrosion</span> thanks to the understanding of oxidation mechanisms. It proposes some <span class="hlt">protection</span> solutions for materials and structures. Content: 1 - <span class="hlt">corrosion</span> costs; macro-economical and metallurgical approach; 2 - basic concepts of thermo-chemistry; 3 - introduction to the Calphad (calculation of phase diagrams) method; 4 - use of the thermodynamic tool: application to pack-cementation; 5 - elements of crystallography and of real solids description; 6 - diffusion in solids; 7 - notions of mechanics inside crystals; 8 - high temperature <span class="hlt">corrosion</span>: phenomena, models, simulations; 9 - pseudo-stationary regime in heterogeneous kinetics; 10 - nucleation, growth and kinetic models; 11 - test experiments in heterogeneous kinetics; 12 - mechanical aspects of metal/oxide systems; 13 - coupling phenomena in high temperature oxidation; 14 - other <span class="hlt">corrosion</span> types; 15 - methods of oxidized surfaces analysis at micro- and nano-scales; 16 - use of SIMS in the study of high temperature <span class="hlt">corrosion</span> of metals and alloys; 17 - oxidation of ceramics and of ceramic matrix composite materials; 18 - <span class="hlt">protective</span> coatings against <span class="hlt">corrosion</span> and oxidation; 19 - high temperature <span class="hlt">corrosion</span> in the 4. generation of nuclear reactor systems; 20 - heat exchangers <span class="hlt">corrosion</span> in municipal waste energy valorization facilities; 21 - high temperature <span class="hlt">corrosion</span> in oil refining and petrochemistry; 22 - high temperature <span class="hlt">corrosion</span> in new energies industry. (J.S.)</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:7267872','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:7267872"><span id="translatedtitle"><span class="hlt">Corrosion</span> behaviour of high chromium ferritic stainless <span class="hlt">steels</span></span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Ferritic <span class="hlt">steels</span> developed for seawater desalination and containing 20 to 28% chromium, up to 5% Mo and additions of nickel and copper have been tested with respect to their <span class="hlt">corrosion</span> behaviour, in particular in chloride containing media. The materials in the sensibilized state were tested for intercrystalline <span class="hlt">corrosion</span> susceptibility in the Strauss-, Streicher-, nitric acid hydrofluoric acid- and Huey-Tests. No intercrystalline <span class="hlt">corrosion</span> was encountered in the case of the <span class="hlt">steels</span> with 28% Cr and 2% Mo. The resistance to pitting was assessed on the basis of rupture potentials determined by potentiokinetic tests. The resistance of the <span class="hlt">steels</span> with 20% Cr and 5% Mo or 28% Cr and 2% Mo is superior to that of the molybdenum containing austenitic types. Addition of nickel yields a significant increase in crevice <span class="hlt">corrosion</span> resistance; the same applies to resistance in sulfuric acid. In boiling seawater all the materials tested are resistant to stress <span class="hlt">corrosion</span> cracking. No sign of any type of <span class="hlt">corrosion</span> was found on nickel containing <span class="hlt">steels</span> after about 6,000 hours exposure to boiling 50% seawater brine even under salt deposits. (orig.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:24021963','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:24021963"><span id="translatedtitle">Intergranular <span class="hlt">corrosion</span> mechanism of stainless <span class="hlt">steels</span> in fuel reprocessing environments</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The intergranular <span class="hlt">corrosion</span> mechanism in stainless <span class="hlt">steels</span> is well explained by the combined effect of environmental and metallurgical factors. As for the environmental factors, the <span class="hlt">corrosion</span> potential is the critical issue. In fuel reprocessing environments, the <span class="hlt">corrosion</span> potentials are expected to be 1200 ± 150 mV (SHE). At the <span class="hlt">corrosion</span> potentials lower than about 1200 mV (SHE) in the passive state <span class="hlt">corrosion</span> potential region, the Cr depleted zone is the main metallurgical factor to induce IGC and compounds such as Ni phosphide (Ni3P2), Laves phase (Fe2Mo) and X phase (Fe18Cr6Mo5) have been confirmed to play the most important role in IGC above about 1200 mV (SHE) in the transpassive state <span class="hlt">corrosion</span> potential region. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:14741142','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:14741142"><span id="translatedtitle">Investigation of sodium phenylanthranilate as an inhibitor of <span class="hlt">steel</span> <span class="hlt">corrosion</span> in neutral media</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Effect of sodium phenylanthranilate (SPhN) on <span class="hlt">corrosion</span> and electrochemical behaviour of armco- and Kh18N10T <span class="hlt">steels</span> is studied in borate buffer solutions (pH=7.36) and in water. It is established that <span class="hlt">protective</span> effect on Kh18N10T <span class="hlt">steels</span> is higher, that is connected with the increased chromium content. Presence of F and CH3COO- ions in studied solutions does not cause the pitting of armco and Kh18N10T <span class="hlt">steels</span>. It is proposed to use SPhN as a practically safe inhibitor</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:34000114','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:34000114"><span id="translatedtitle"><span class="hlt">Corrosion</span> and erosion-<span class="hlt">corrosion</span> behaviors of carbon <span class="hlt">steel</span> in naphthenic acid media</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The naphthenic acid <span class="hlt">corrosion</span> (NAC) and erosion-<span class="hlt">corrosion</span> (NAEC) behaviors of carbon <span class="hlt">steel</span> were investigated detailedly in laboratory. The resistance to NAEC of pack-aluminized carbon <span class="hlt">steel</span> and carbon <span class="hlt">steel</span> coated by high velocity oxygen-fuel (HVOF) thermal-sprayed AISI 316L stainless <span class="hlt">steel</span>, was also investigated in both laboratory and an oil refinery. It was found that the control-step of NAC was primarily dependent on the temperature. The NAC rate of carbon <span class="hlt">steel</span> increased markedly with the increase of the total acid number and temperature, which may be attributed to the enhanced absorption and active reaction of naphthenic acid molecules on the metal surface. Increasing the velocity of flow seriously aggravated NAEC, especially in the high temperature range. The reasons were closely associated with the enhanced mass transfer and the accelerated active reaction as well as the rapid spallation of <span class="hlt">corrosion</span> products from the metal surface. Both the aluminized carbon <span class="hlt">steel</span> and the carbon <span class="hlt">steel</span> covered by HVOF coating showed better resistance against NAEC compared to the carbon <span class="hlt">steel</span> due to higher microhardness and <span class="hlt">corrosion</span> resistance of their surface-layers. The HVOF coating is hopeful to be applied for NAEC prevention of the components in oil refineries in view of present experimental results. (Abstract Copyright [2002], Wiley Periodicals, Inc.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.etde.org/etdeweb/servlets/purl/371211-L31QiX/webviewable/','ETDEWEB-EN'); return false;" href="https://www.etde.org/etdeweb/servlets/purl/371211-L31QiX/webviewable/"><span id="translatedtitle"><span class="hlt">Corrosion</span> of mild <span class="hlt">steel</span> in simulated cesium elution process solutions</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Elmore, M.R.</p> <p>1996-09-01</p> <p>The West Valley Support Project is being conducted to meet technology needs for the West Valley Demonstration Project and to provide support to the site cleanup and stabilization activities, which involves removing residual Cs in Tank 8D-1 after waste retrieval. In-tank oxalic acid elution of Cs-loaded zeolite is being evaluated. The work reported here involved evaluating the potential for increased <span class="hlt">corrosion</span> of Tank 8D-1 during Cs elution, because oxalic acid is <span class="hlt">corrosive</span> to carbon <span class="hlt">steel</span>. This included <span class="hlt">corrosion</span> tests with mild <span class="hlt">steel</span> (A516 Grade 55) at 27-50 C with 4 and 8 wt% oxalic acid, for 2, 4, and 6 days. Results agreed with Sept. 1995 tests at 50 C for 1-3 weeks. <span class="hlt">Corrosion</span> rate of A516 Grade 55 mild <span class="hlt">steel</span> in oxalic acid is quite high (about 150 mils/y or 3.8 mm/y). <span class="hlt">Corrosion</span> increased three- or fourfold going from 27 to 50 C. Although the tests resulted in a very rough surface appearance, indicating potential for localized <span class="hlt">corrosion</span>, eg, pitting and crevice <span class="hlt">corrosion</span>, the exposure times used were apparently too short to initiate pitting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:38088417','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:38088417"><span id="translatedtitle"><span class="hlt">Corrosion</span> of <span class="hlt">steel</span> tanks in liquid nuclear wastes</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The objective of this work is to understand how solution chemistry would impact on the <span class="hlt">corrosion</span> of waste storage <span class="hlt">steel</span> tanks at the Hanford Site. Future tank waste operations are expected to process wastes that are more dilute with respect to some current <span class="hlt">corrosion</span> inhibiting waste constituents. Assessment of <span class="hlt">corrosion</span> damage and of the influence of exposure time and electrolyte composition, using simulated (non-radioactive) wastes, of the double-shell tank wall carbon <span class="hlt">steel</span> alloys is being conducted in a statistically designed long-term immersion experiment. <span class="hlt">Corrosion</span> rates at different times of immersion were determined using both weight-loss determinations and electrochemical impedance spectroscopy measurements. Localized <span class="hlt">corrosion</span> susceptibility was assessed using short-term cyclic potentiodynamic polarization curves. The results presented in this paper correspond to electrochemical and weight-loss measurements of the immersed coupons during the first year of immersion from a two year immersion plan. A good correlation was obtained between electrochemical measurements, weight-loss determinations and visual observations. Very low general <span class="hlt">corrosion</span> rates (-1) were estimated using EIS measurements, indicating that general <span class="hlt">corrosion</span> rate of the <span class="hlt">steel</span> in contact with liquid wastes would no be a cause of tank failure even for these out-of-chemistry limit wastes. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:45077915','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:45077915"><span id="translatedtitle"><span class="hlt">Corrosion</span> mitigation by photo-catalytic coatings for stainless <span class="hlt">steels</span></span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Incidents of intergranular stress <span class="hlt">corrosion</span> cracking (IGSCC) have occurred in boiling water reactors (BWRs) for decades. The electrochemical <span class="hlt">corrosion</span> potential (ECP) is currently a major indicator for the IGSCC susceptibility of stainless <span class="hlt">steel</span> (SS) components in BWR environments. This study proposes a novel technique of photo-catalytic treatment to mitigate the IGSCC problems in BWRs that could eventually lead to a lower demand of dissolved hydrogen for hydrogen water chemistry (HWC). Zirconium dioxide (ZrO2) and titanium dioxide (TiO2) were selected as the coating material for <span class="hlt">corrosion</span> mitigation of Type 304 stainless <span class="hlt">steel</span> (SS) in high temperature water. Electrochemical polarization analyses were conducted to investigate the <span class="hlt">corrosion</span> behavior of both treated and untreated samples in 288degC pure water with O2 concentration of 300 ppb. Ultraviolet (UV) irradiation was then imposed upon the treated samples to examine if there was any photoelectric effect on the <span class="hlt">corrosion</span> behavior of the treated samples. According to the experimental results, the ECPs of the treated samples with UV became lower than those without UV, and the <span class="hlt">corrosion</span> rates of the treated with UV irradiation were actually lower, as expected. These results indicate that the ZrO2 or TiO2 treatment in combination with UV radiation would effectively reduce the <span class="hlt">corrosion</span> rate of Type 304 stainless <span class="hlt">steels</span> in high temperature oxygenated environments. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=20769429','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=20769429"><span id="translatedtitle">Microbiologically influenced <span class="hlt">corrosion</span> of <span class="hlt">steels</span> by thermophilic and mesophilic bacteria</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Alfaro-Cuevas-Villanueva, R.; Cortes-Martinez, R.; Galvan-Martinez, R.; Torres-Sanchez, R. [Universidad Michoacana de San Nicolas de Hidalgo, Instituto de Investigaciones Metalurgicas, Edificio ' ' U' ' , C.U. Apartado Postal 52-B, CP, 58000, Morelia, Michoacan (Mexico); Garcia-Diaz, J.J. [Instituto Tecnologico de Morelia, Centro de Graduados, Morelia, Michoacan (Mexico)</p> <p>2006-07-15</p> <p>Bacterial influenced <span class="hlt">corrosion</span> of AISI 316 stainless <span class="hlt">steels</span> (SS) and ASTM A36 carbon <span class="hlt">steel</span> by two strains of sulfate reducing bacteria (SRB) were analyzed. Thermophilic and mesophilic bacteria were isolated from the condensate fluid of ''Los Azufres'', a geothermal electric field located in the State of Michoacan at Central Mexico. Anaerobic <span class="hlt">corrosion</span> tests were carried out for 15, 30 and 60 days in lactate-containing media at 50 C and 40 C. Scanning electron microscopy (SEM) was used to determine <span class="hlt">corrosion</span> morphology. Pitting density was determined with an optical microscope. <span class="hlt">Corrosion</span> potential, anodic potentiodynamic polarization curves and pH values were measured under anaerobic conditions. Results show that the microbial activity influenced the overall <span class="hlt">corrosion</span> process, whereas, pitting <span class="hlt">corrosion</span> and localized attack <span class="hlt">corrosion</span> (LAC) were found. The anodic polarization curves show that passivation and activation processes should take place on the <span class="hlt">steel</span> surface of the sample and pH decreases as the exposure time increases. (Abstract Copyright [2006], Wiley Periodicals, Inc.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pub.iapchem.org/ojs/index.php/JESE/article/view/242','DOAJ-ART-EN'); return false;" href="http://pub.iapchem.org/ojs/index.php/JESE/article/view/242"><span id="translatedtitle">Inhibition of carbon <span class="hlt">steel</span> <span class="hlt">corrosion</span> by 11-aminoundecanoic acid</span></a></p> <p><a target="_blank" href="http://www.doaj.org/doaj?func=searchArticles">Directory of Open Access Journals (Sweden)</a></p> <p>Saad Ghareba</p> <p>2015-12-01</p> <p>Full Text Available The current study reports results on the investigation of the possibility of using 11-aminoundecanoic acid (AA as an inhibitor of general <span class="hlt">corrosion</span> of carbon <span class="hlt">steel</span> (CS in HCl under a range of experimental conditions: inhibitor concentration, exposure time, electrolyte temperature and pH and CS surface roughness. It was found that AA acts as a mixed-type inhibitor, yielding maximum inhibition efficiency of 97 %. The adsorption of AA onto the CS surface was described by the Langmuir adsorption isotherm. The corresponding apparent Gibbs free energy of AA adsorption on CS at 295 K was calculated to be ?30.2 kJ mol–1. The adsorption process was found to be driven by a positive change in entropy of the system. PM-IRRAS measurements revealed that the adsorbed AA layer is amorphous, which can be attributed to the repulsion between the neighboring positively charged amine groups and a high heterogeneity of the CS surface. It was also found that the AA provides very good <span class="hlt">corrosion</span> <span class="hlt">protection</span> of CS of various surface roughness, and over a prolonged time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:40049147','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:40049147"><span id="translatedtitle">Polyethyleneimine as a <span class="hlt">corrosion</span> inhibitor for ASTM 420 stainless <span class="hlt">steel</span> in near-neutral saline media</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The effect of polyethyleneimine (PEI) as a <span class="hlt">corrosion</span> inhibitor for ASTM 420 stainless <span class="hlt">steel</span> in 3% aqueous NaCl solution was studied. The results of linear polarization and cyclic polarization measurements indicate high inhibiting effectiveness of the selected organics. Moreover, from cyclic polarization measurements it can be deduced that PEI acts as an inhibitor against pitting <span class="hlt">corrosion</span>. Immersion tests in the presence of PEI showed remarkable <span class="hlt">corrosion</span> <span class="hlt">protection</span> against uniform <span class="hlt">corrosion</span>. Film persistency immersion testing indicated that once the <span class="hlt">protective</span> layer is formed, it is very stable in a non-inhibited NaCl solution. X-ray photoelectron spectroscopy measurements showed that PEI binding is mediated by electrostatic interactions between PEI and the substrate. A dense layer of PEI might be effective either in preventing diffusion of ionic species from the film or in preventing attack by chlorine from the salt water</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=21270076','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=21270076"><span id="translatedtitle">Susceptibility to <span class="hlt">corrosion</span> damage of pipeline <span class="hlt">steels</span> under coating disbondments</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Guermazi, N.; Ibrahmi, A.; Hmidi, H.; Elleuch, K.; Ayedi, H.F. [Unite de Recherche de Chimie Industrielle et Materiaux, URCIM - ENIS, Sfax (Tunisia)</p> <p>2010-01-15</p> <p>This study provides an experimental investigation on the <span class="hlt">corrosion</span> behaviour of three carbon <span class="hlt">steels</span> used for pipeline application. The susceptibility of these materials to <span class="hlt">corrosion</span> damage was analysed in order to simulate its service conditions particularly under disbonded coating. Monitoring of open-circuit potential (E{sub free}), polarization resistance (R{sub p}) and measuring of the weight loss during immersion time were used to evaluate the <span class="hlt">corrosion</span> behaviour of the studied materials. All the <span class="hlt">corrosion</span> experiments were performed in two aqueous solutions: natural seawater and synthetic one (3 wt% NaCl solution). The morphology of the <span class="hlt">corrosion</span> products was examined by optical microscopy. The results obtained from electrochemical tests have shown different behaviour for the studied <span class="hlt">steels</span> into the retained <span class="hlt">corrosive</span> environments: more stable potentials (E{sub free}), higher R{sub p}-values with large fluctuations evolution were found in natural seawater. The gravimetric measurements have also shown a continuous variation of the weight loss throughout the exposure period in the sodium chloride solution. However, it seemed that a passive behaviour was observed in natural seawater. A little difference was observed between all the studied <span class="hlt">steels</span> in terms of <span class="hlt">corrosion</span> kinetics. The <span class="hlt">steel</span>, having the little ferritic grain size, seems to be more resistant to <span class="hlt">corrosion</span> damage. Qualitatively, a porous and non-adherent oxide film was observed on the corroded surface in the synthetic solution; while, the rust layer, which is formed in the natural seawater, has acted as a barrier of <span class="hlt">corrosion</span> process. Finally, all the results obtained from both electrochemical tests and weight loss measurements were in reasonably good accordance. The important common point that can be concluded was that all the tested materials seem to be more suitable for natural seawater than 3 wt% NaCl solution. Also, they are not recommendable to be used in an environment where chloride attack is possible and important. (Abstract Copyright [2010], Wiley Periodicals, Inc.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25839822','SCIGOV-EN'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25839822"><span id="translatedtitle">Performance evaluation of pectin as ecofriendly <span class="hlt">corrosion</span> inhibitor for X60 pipeline <span class="hlt">steel</span> in acid medium: experimental and theoretical approaches.</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Umoren, Saviour A; Obot, Ime B; Madhankumar, A; Gasem, Zuhair M</p> <p>2015-06-25</p> <p>The <span class="hlt">corrosion</span> inhibition effect of pectin (a biopolymer) for X60 pipeline <span class="hlt">steel</span> in HCl medium was investigated using weight loss, electrochemical, water contact angle measurements, and scanning electron microscopy techniques. The results obtained show that pectin acts as a good <span class="hlt">corrosion</span> inhibitor for X60 <span class="hlt">steel</span>. Inhibition efficiency increased with increase in pectin concentration and temperature. Potentiodynamic polarization results reveal that pectin could be classified as a mixed-type <span class="hlt">corrosion</span> inhibitor with predominant control of the cathodic reaction. The effective <span class="hlt">corrosion</span> inhibition potential of pectin could be related to the adsorption of pectin molecules at the metal/solution interface which is found to accord with the Langmuir adsorption isotherm model and a <span class="hlt">protective</span> film formation. Quantum chemical calculations provided insights into the active sites and reactivity parameters governing pectin activity as a good <span class="hlt">corrosion</span> inhibitor for X60 <span class="hlt">steel</span>. PMID:25839822</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=od_______942::6b4232b0ce1041b1642e7a727b30dd2b','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=od_______942::6b4232b0ce1041b1642e7a727b30dd2b"><span id="translatedtitle">Analysis of stray current induced by cathodic <span class="hlt">protection</span> on <span class="hlt">steel</span>-framed masonry structures</span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>Wu, YY; P. Lambert; Mangat, Pal; O'Flaherty, Fin</p> <p>2011-01-01</p> <p>Cathodic <span class="hlt">protection</span> (CP) has been successfully employed to <span class="hlt">protect</span> <span class="hlt">steel</span>-framed masonry buildings from <span class="hlt">corrosion</span> related damage. When a CP system is installed to <span class="hlt">protect</span> the structural members, other metallic items which are within the fabric of the structure but are not in direct electrical continuity may suffer from stray current interactions, resulting in accelerated <span class="hlt">corrosion</span> of the discontinuous items. Therefore, these must be considered when CP systems are designed prior to installation...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=od_______912::bd6ff5c84f76add77fd700a8403e6df2','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=od_______912::bd6ff5c84f76add77fd700a8403e6df2"><span id="translatedtitle">Boro-aluminising of P91 <span class="hlt">steel</span> by pack cementation for <span class="hlt">protection</span> against steam oxidation</span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>Omar, H.; Tsipas, Sophia Alexandra; Maragoudakis, N; Michailidis, N.</p> <p>2011-01-01</p> <p>High performance alloys are often the materials used for various components exposed to high temperature environments. In many cases, <span class="hlt">protective</span> coatings are applied in these alloys, providing higher <span class="hlt">corrosion</span> and oxidation resistance, compared to the base material. This study investigates the feasibility to apply boro-aluminising treatment on P91 <span class="hlt">steel</span> by pack cementation process, to increase the <span class="hlt">steel</span> high temperature properties in oxidising and <span class="hlt">corrosive</span> environments. Packs activated...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:46099524','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:46099524"><span id="translatedtitle">The synergistic effect of polyamidoamine dendrimers and sodium silicate on the <span class="hlt">corrosion</span> of carbon <span class="hlt">steel</span> in soft water</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Highlights: • The composite demonstrated synergistic effects and exhibited mixed-type <span class="hlt">corrosion</span> inhibition behavior. • The composite showed remarkable <span class="hlt">corrosion</span> inhibition property at a relatively low dosage. • The composite functioned more environmental-friendly compared to traditional inhibitors. • The composite have been adsorbed on the carbon <span class="hlt">steel</span> surface as a <span class="hlt">protective</span> film against <span class="hlt">corrosion</span> attack. - Abstract: The <span class="hlt">corrosion</span> inhibition properties of a combination of polyamidoamine dendrimers and sodium silicate for carbon <span class="hlt">steel</span> in soft water has been examined and characterized by weight loss measurements, Tafel polarization, electrochemical impedance spectroscopy (EIS), energy-dispersive X-ray spectroscopy (EDS) and atomic force microscopy (AFM). The results show that this environmental friendly <span class="hlt">corrosion</span> inhibitor at relatively low dosages had a good inhibition effect on the carbon <span class="hlt">steel</span> <span class="hlt">corrosion</span> in soft water. The adsorption of a combination of polyamidoamine dendrimers and sodium silicate obeys a Langmuir adsorption isotherm. Potentiodynamic polarization studies show that the <span class="hlt">corrosion</span> inhibitor was a mixed inhibitor. EDS determined the nature of the adsorption layer on the <span class="hlt">steel</span> surfaces, and AFM further confirmed the formation of a <span class="hlt">protective</span> film on the carbon <span class="hlt">steel</span> surface</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=doajarticles::5153bd9d8da36ab02a7225bc12bcaa13','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=doajarticles::5153bd9d8da36ab02a7225bc12bcaa13"><span id="translatedtitle">Optimal Piling Network <span class="hlt">Corrosion</span> <span class="hlt">Protection</span> System for Al-Zubair Harbor</span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>Mohammed H. Hafiz; Wisam K. Hamdan; Ruaa Kaream Salman</p> <p>2012-01-01</p> <p>Cathodic <span class="hlt">protection</span> is an effective electrochemical technique for preventing <span class="hlt">corrosion</span> of metallic structures, for large structures like piles network impressed current cathodic <span class="hlt">protection</span> (ICCP) system is usually preferred. The main aim of this study is to obtain the optimum <span class="hlt">protection</span> potential that would provide a full cathodic <span class="hlt">protection</span> for <span class="hlt">steel</span> piles net-work immersed in sea water at Al-Zubair harbor. The effect of one immeasurable factor (path of anode (?<sub>1</sub>)) and...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:43023393','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:43023393"><span id="translatedtitle">Recent Research and Development in Solving Atmospheric <span class="hlt">Corrosion</span> Problems of <span class="hlt">Steel</span> Industries in Japan</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>A rust layer, so called '<span class="hlt">protective</span>' rust layer, on a weathering low-alloy <span class="hlt">steel</span> has strong <span class="hlt">protective</span> ability for atmospheric <span class="hlt">corrosion</span> of the <span class="hlt">steel</span>. We have recently found through a large number of spectroscopic studies including Moessbauer spectroscopy that the <span class="hlt">protective</span> rust layer forms after long-term phase transformation. The phase and structure of the rust definitely control the <span class="hlt">protective</span> ability of the rust layer. From this recent knowledge, some new technologies have been developed. One is the surface-treatment technique that provides a possibility for obtaining the <span class="hlt">protective</span> rust layer in a relatively short period even in the severe environments such as in marine and chloride (de-icing salts) containing environments. Others are based on selection of effective alloying elements for <span class="hlt">steel</span> materials. These are particularly important for application in areas where <span class="hlt">protective</span> rust layer formation may be hindered or prevented. In this paper, we mention recent progress in research and development on rusting <span class="hlt">protection</span> by rust for atmospheric <span class="hlt">corrosion</span> of <span class="hlt">steels</span> in Japan.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JTST...21..987H','SCIGOV-EN'); return false;" href="http://adsabs.harvard.edu/abs/2012JTST...21..987H"><span id="translatedtitle">Influence of Processing and Heat Treatment on <span class="hlt">Corrosion</span> Resistance and Properties of High Alloyed <span class="hlt">Steel</span> Coatings</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Hill, Horst; Weber, Sebastian; Raab, Ulrich; Theisen, Werner; Wagner, Lothar</p> <p>2012-09-01</p> <p><span class="hlt">Corrosion</span> and abrasive wear are two important aspects to be considered in numerous engineering applications. Looking at <span class="hlt">steels</span>, high-chromium high-carbon tool <span class="hlt">steels</span> are proper and cost-efficient materials. They can either be put into service as bulk materials or used as comparatively thin coatings to <span class="hlt">protect</span> lower alloyed construction or heat treatable <span class="hlt">steels</span> from wear and <span class="hlt">corrosion</span>. In this study, two different <span class="hlt">corrosion</span> resistant tool <span class="hlt">steels</span> were used for the production of coatings and bulk material. They were processed by thermal spraying and super solidus liquid phase sintering as both processes can generally be applied to produce coatings on low alloyed substrates. Thermally sprayed (high velocity oxygen fuel) coatings were investigated in the as-processed state, which is the most commonly used condition for technical applications, and after a quenching and tempering treatment. In comparison, sintered <span class="hlt">steels</span> were analyzed in the quenched and tempered condition only. Significant influence of alloy chemistry, processing route, and heat treatment on tribological properties was found. Experimental investigations were supported by computational thermodynamics aiming at an improvement of tribological and <span class="hlt">corrosive</span> resistance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MMTB..tmp...51M','SCIGOV-EN'); return false;" href="http://adsabs.harvard.edu/abs/2015MMTB..tmp...51M"><span id="translatedtitle">Effect of Acidified Feronia elephantum Leaf Extract on the <span class="hlt">Corrosion</span> Behavior of Mild <span class="hlt">Steel</span></span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Muthukrishnan, Pitchaipillai; Prakash, Periakaruppan; Ilayaraja, Murugan; Jeyaprabha, Balasubramanian; Shankar, Karikalan</p> <p>2015-03-01</p> <p>Mild <span class="hlt">steel</span> is used as a structural material for pipes, tank, reaction vessels, etc. which are known to corrode invariably in contact with various solvents. From the view point of a nation's economy and financial implications of <span class="hlt">corrosion</span> hazard, it is necessary to adopt appropriate means and ways to reduce the losses due to <span class="hlt">corrosion</span>. The use of eco-friendly <span class="hlt">corrosion</span> inhibitors are increasing day by day. Feronia elephantum leaf extract (FELE) has been tested as eco-friendly <span class="hlt">corrosion</span> inhibitor for A262 mild <span class="hlt">steel</span> in 1 M H2SO4 and 1 M HCl solutions using non-electrochemical (Gravimetric, X-ray diffraction analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy) and electrochemical techniques (open circuit potential, potentiostatic polarization, and electrochemical impedance measurements). The <span class="hlt">protection</span> efficiency is found to increase with increase in FELE concentration but decrease with temperature, which is suggestive of physical adsorption mechanism. The adsorption of FELE on mild <span class="hlt">steel</span> surface obeys the Langmuir adsorption isotherm. SEM results confirm the formation of a <span class="hlt">protective</span> layer by FELE over mild <span class="hlt">steel</span> surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:40019821','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:40019821"><span id="translatedtitle">Multilayer coatings for <span class="hlt">corrosion</span> <span class="hlt">protection</span> of coal gasifier components</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Deposition of TiAlN/Nb, TiAlN/Ta, TiAlN/W and TiAlN/Zr multilayer coatings on 409 stainless <span class="hlt">steel</span> was studied by CVD in a fluidized bed reactor (FBR-CVD). The coatings consisted of four TiAlN layers with individual thickness of 2.5-3.5 ?m, and four metal interlayers with thicknesses in the range of 100-250 nm. The W interlayers suffered partial nitridation during the coating process and the resulting coatings had poor adhesion. Deposition of Zr through reduction of ZrI4 by H2 was found to be inefficient. Both TiAlN/Nb and TiAlN/Ta coatings showed good adhesion, but only TiAlN/Nb provided sulfidation resistance to 409 <span class="hlt">steel</span> during exposure to simulated coal gas at 1173 K for 300 h. Though outward diffusion of Cr took place during the <span class="hlt">corrosion</span> test, the results reported in this paper suggest that TiAlN/Nb coatings are promising candidates for <span class="hlt">corrosion</span> <span class="hlt">protection</span> of <span class="hlt">steels</span> under typical coal gasifier conditions</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26647950','SCIGOV-EN'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26647950"><span id="translatedtitle"><span class="hlt">Corrosion</span> of connectors used in equipment <span class="hlt">protecting</span> against falls from a height.</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Jachowicz, Marcin</p> <p>2015-01-01</p> <p>Connectors are commonly found in personal equipment <span class="hlt">protecting</span> against falls from a height. They are typically used outdoors and exposed to atmospheric factors, which can result in <span class="hlt">corrosion</span>. This article presents the results of a study involving exposure of connectors to experimental <span class="hlt">corrosive</span> media - neutral salt spray (NSS), acid salt spray (ASS), and seawater mist (for elements made of carbon <span class="hlt">steel</span> and non-ferrous metals) - and to experimental conditions simulating the processes of pitting, stress, and intercrystalline <span class="hlt">corrosion</span> (for equipment made of s`tainless <span class="hlt">steel</span>). The results indicate that the main effects of <span class="hlt">corrosion</span> on connectors include impaired operation and reduced strength of their mobile elements. The article presents methods of testing connector operation developed for this purpose. <span class="hlt">Corrosive</span> damage to connectors has been presented in relation to potential hazards for their users. PMID:26647950</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.etde.org/etdeweb/servlets/purl/22012568/','ETDEWEB-EN'); return false;" href="https://www.etde.org/etdeweb/servlets/purl/22012568/"><span id="translatedtitle">Development of Nb{sub 2}O{sub 5}|Cu composite as AISI 1020 <span class="hlt">steel</span> thermal spray coating for <span class="hlt">protection</span> against <span class="hlt">corrosion</span> by soil in buried structures; Desenvolvimento e uso do composito de Nb{sub 2}O{sub 5}|Cu como revestimento aplicado por aspersao termica sobre o aco AISI 1020 para protecao contra a corrosao pelo solo em estruturas enterradas</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Regis Junior, Oscar [Universidade Tecnologica Federal do Parana, Ponta Grossa, PR (Brazil). Dept. de Mecanica; Silva, Jose Maurilio da; Portella, Kleber Franke [Instituto de Tecnologia para o Desenvolvimento, Curitiba, PR (Brazil). Dept. de Pesquisa em Engenharia Civil; Paredes, Ramon Sigifredo Cortes, E-mail: regis@utfpr.edu.br [Universidade Federal do Parana, Curitiba, PR (Brazil). Dept. de Mecanica</p> <p>2012-07-01</p> <p>An Nb{sub 2}O|Cu <span class="hlt">corrosion</span>-resistant coating was developed and applied onto AISI 1020 <span class="hlt">steel</span> substrate by Powder Flame Spray. A galvanostatic electrochemical technique was employed, with and without ohmic drop, in four different soils (two <span class="hlt">corrosively</span> aggressive and two less aggressive). Behavior of coatings in different soils was compared using a cathodic hydrogen reduction reaction (equilibrium potential, overvoltage and exchange current density) focusing on the effect of ohmic drop. Results allow recommendation of Nb{sub 2}O{sub 5}|Cu composite for use in buried structure <span class="hlt">protection</span>. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://drs.nio.org/drs/handle/2264/2994','DRSNIO-EN'); return false;" href="http://drs.nio.org/drs/handle/2264/2994"><span id="translatedtitle"><span class="hlt">Corrosion</span> of mild <span class="hlt">steel</span>, copper and brass in crude oil / seawater mixture</span></a></p> <p><a target="_blank" href="http://drs.nio.org/drs/advanced-search">Digital Repository Service at National Institute of Oceanography (India)</a></p> <p>PrabhaDevi, S.; Sawant, S.S.; Wagh, A.B.</p> <p></p> <p>Mild <span class="hlt">steel</span>, copper and brass coupons were introduced in natural seawater containing varying amount of crude oil. Mild <span class="hlt">steel</span> showed higher rate of <span class="hlt">corrosion</span> in seawater containing oil and lower <span class="hlt">corrosion</span> rate in natural as well as artificial seawater...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:32044929','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:32044929"><span id="translatedtitle">Results of <span class="hlt">steel</span> <span class="hlt">corrosion</span> tests in flowing liquid Pb/Bi at 420-600 deg. C after 2000 h</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p><span class="hlt">Corrosion</span> tests were carried out on austenitic AISI 316L and 1.4970 <span class="hlt">steel</span> and on MANET <span class="hlt">steel</span> up to 2000 h of exposure to flowing (up to 2 m/s) Pb/Bi. The concentration of oxygen in the liquid alloy was controlled at 10-6 wt%. Specimens consisted of tube and rod sections in original state and after alloying of Al into the surface. After 2000 h of exposure at 420 and 550 deg. C the specimen surfaces were covered with an intact oxide layer which provided a good <span class="hlt">protection</span> against <span class="hlt">corrosion</span> attack of the liquid Pb/Bi alloy. At the same time <span class="hlt">corrosion</span> attack at 600 deg. C was severe at the original AISI 316L <span class="hlt">steel</span> specimens. The alloyed specimens containing FeAl on the surface of the alloyed layer still maintained an intact oxide layer with good <span class="hlt">corrosion</span> <span class="hlt">protection</span> up to 600 deg. C. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:39009225','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:39009225"><span id="translatedtitle">Electrochemical <span class="hlt">Corrosion</span> Testing of Borated Stainless <span class="hlt">Steel</span> Alloys</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The Department of Energy Office of Civilian Radioactive Waste Management has specified borated stainless <span class="hlt">steel</span> manufactured to the requirements of ASTM A 887-89, Grade A, UNS S30464, to be the material used for the fabrication of the fuel basket internals of the preliminary transportation, aging, and disposal canister system preliminary design. The long-term <span class="hlt">corrosion</span> resistance performance of this class of borated materials must be verified when exposed to expected YMP repository conditions after a waste package breach. Electrochemical <span class="hlt">corrosion</span> tests were performed on crevice <span class="hlt">corrosion</span> coupons of Type 304 B4 and Type 304 B5 borated stainless <span class="hlt">steels</span> exposed to single postulated in-package chemistry at 60 C. The results show low <span class="hlt">corrosion</span> rates for the test period</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:32067779','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:32067779"><span id="translatedtitle"><span class="hlt">Corrosion</span> testing of stainless <span class="hlt">steel</span>-zirconium metal waste form</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Stainless <span class="hlt">steel</span>-zirconium (SS-Zr) alloys are being considered as waste forms for the disposition of metallic waste generated during the electrometallurgical treatment of spent nuclear fuel. The waste forms contain irradiated cladding hulls, components of the alloy fuel, noble metal fission products, and actinide elements. The baseline waste form is a stainless <span class="hlt">steel</span>-15 wt% zirconium (SS-15Zr) alloy. This article presents microstructure and some of the <span class="hlt">corrosion</span> studies being conducted on the waste form alloys. Electrochemical <span class="hlt">corrosion</span>, immersion <span class="hlt">corrosion</span>, and vapor hydration tests have been performed on various alloy compositions to evaluate <span class="hlt">corrosion</span> behavior and resistance to selective leaching of simulated fission products. The SS-Zr waste forms are successful at the immobilization and retention of fission products and show potential for acceptance as high-level nuclear waste forms</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014HTMP...33..489F','SCIGOV-EN'); return false;" href="http://adsabs.harvard.edu/abs/2014HTMP...33..489F"><span id="translatedtitle">Effect of Different Treatment on <span class="hlt">Corrosion</span> Resistance of Sputtered Al Coating on Stainless <span class="hlt">Steel</span></span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Fu, Guangyan; Qi, Zeyan; Su, Yong; Liu, Qun; Guo, Xingxing</p> <p>2014-12-01</p> <p>Aluminum coating on 1Cr18Ni9Ti stainless <span class="hlt">steel</span> was prepared by magnetron sputtering method. The specimens were treated with pre-oxidation (PO) or vacuum diffusion annealing (VA). Hot <span class="hlt">corrosion</span> resistance of the coatings beneath the deposits of Na2SO4 at 1050 °C was investigated. <span class="hlt">Corrosion</span> products were analyzed by XRD and SEM. Results show that the presence of coating could improve the <span class="hlt">corrosion</span> resistance of stainless <span class="hlt">steel</span>. FeAl phase appeared after VA at 600 °C, which enhanced cohesive force between the coating and the substrate, and reduced the oxidation and sulfidation rate. PO treatment can <span class="hlt">protect</span> the substrate more effectively than VA treatment for metastable Al2O3 formed during PO treatment can be translated to stable Al2O3 more quickly at high temperatures. The <span class="hlt">corrosion</span> products of the two kinds of specimens with aluminum coating were both composed of Al2O3, a little amount of FeS and Fe2O3 after 24 h <span class="hlt">corrosion</span>. Al2O3 was formed mainly in the coatings, FeS was mainly distributed in the interface between coating and substrate of the specimens, and a small amount of FeS was distributed in the substrate. Al2O3 film remained intact after 24 h <span class="hlt">corrosion</span>, and kept its <span class="hlt">protective</span> effect on the substrate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=21110935','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=21110935"><span id="translatedtitle"><span class="hlt">Corrosion</span> <span class="hlt">protection</span> - less defects, more operational safety</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Calin, Cristian; Mihai Filip, Stefan [E.ON Gaz Distributie SA Targu-Mure (Romania). Network Management Div.</p> <p>2008-11-15</p> <p>Beginning with June 2005, the year of the Distrigaz Nord privatization, new technical approaches started to be implemented. A <span class="hlt">steel</span> pipeline rehabilitation strategy was initiated according to European and Romanian Norms, as well as western technology, in order to improve the operational safety. Thus, a few important directions were established: replacement or repairing of old <span class="hlt">steel</span> grids, which are in bad technical condition with polyethylene or <span class="hlt">steel</span> pipelines and cathodic <span class="hlt">protection</span> for grids worth to be <span class="hlt">protected</span>, according to the E.ON Ruhrgas technology. These rehabilitations are performed both by our own and by third party companies. In the near future a complex data base (collected within the framework of the P.I.M.S. activity - pipeline integrity management system) will support this strategy. New leak detection techniques as well as pipeline repairing techniques were also implemented. All these operation and construction activities are improved by new techniques, procedures, equipments and trainings. (orig.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=od_______935::052c277da40fca0f27514bc34f969cae','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=od_______935::052c277da40fca0f27514bc34f969cae"><span id="translatedtitle"><span class="hlt">Corrosion</span> behaviour at the interface of <span class="hlt">steel</span> bars embedded in cement slurries: effect of phenol polymer coatings</span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>García Andión, Luis; Garcés Terradillos, Pedro; Lapuente Aragó, Rocío; Vázquez Picó, José Luis; Cases Iborra, Francisco Javier</p> <p>2002-01-01</p> <p>Cyclic voltammetry has been employed to investigate the behaviour of carbon <span class="hlt">steel</span> and stainless <span class="hlt">steel</span> electrodes in solutions obtained by ?ltering of calcium aluminate cement and portland cement slurries. Electro-polymerized phenol coating on <span class="hlt">steel</span> electrodes has also been studied in carbonate medium. The phenol electro-polymerization occurs on a passivated surface and leads to adherent and stable polymeric ?lm exhibiting a partial <span class="hlt">protection</span> against <span class="hlt">corrosion</span>. The Fourier transform infrar...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.etde.org/etdeweb/servlets/purl/20671815-J8q2Qy/','ETDEWEB-EN'); return false;" href="https://www.etde.org/etdeweb/servlets/purl/20671815-J8q2Qy/"><span id="translatedtitle">Oil field chemicals synergistic effects on the <span class="hlt">corrosion</span> rate of L-80 <span class="hlt">steel</span> in sea and formation waters</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Al Hashem, A.; Carew, J. [Petroleum Research and Studies Center, Kuwait Institute for Scientific Research, P.O. Box 24885, 13109 Safat Kuwait (Kuwait); Al-Borno, A. [Charter Coating Service (2000) Ltd., no 6, 4604, 13 Street N.E., Calgary, AB T2E 6P1 (Canada)</p> <p>2004-07-01</p> <p>The <span class="hlt">corrosion</span> rate of tubular grade L-80 carbon <span class="hlt">steel</span> under downhole conditions of a northern oil field of Kuwait was investigated. This was done using the injection seawater, formation water and a 50:50 mixture of both waters in the presence of commercially available <span class="hlt">corrosion</span> inhibitor, scale inhibitor, and biocide products separately and in combination with each other. The main objective of this study was to investigate the effect of the <span class="hlt">corrosion</span> inhibitor and its interaction with the scale inhibitor and the biocide, as seen in the <span class="hlt">corrosion</span> rate of L80 carbon <span class="hlt">steel</span>. This was done using the manufacturers' recommended dosage levels of the <span class="hlt">corrosion</span> inhibitor, scale inhibitor and biocide. The <span class="hlt">corrosion</span> rates were measured by linear polarization. Tests were conducted using the rotating cylinder electrode method with rotational speeds of 1000 and 2000 rpm at 80 deg. C. The seawater results indicated that the <span class="hlt">corrosion</span>-scale inhibitor and biocide-scale inhibitor combinations provided the best <span class="hlt">protection</span> at both rotation speeds. In formation water, the effects of rotation speed were more apparent with higher <span class="hlt">corrosion</span> rates of L-80 carbon <span class="hlt">steel</span> accompanying higher shear forces. In the 50: 50 mix waters and the formation water, the <span class="hlt">corrosion</span>-scale inhibitors-biocide combination provided the best <span class="hlt">protection</span> at both rotational speeds under downhole conditions of a northern oil field of Kuwait. (authors)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=dedup_wf_001::4bc6f424b09ea8f104a3f740e4c9081f','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=dedup_wf_001::4bc6f424b09ea8f104a3f740e4c9081f"><span id="translatedtitle">Characterization of <span class="hlt">corrosion</span> products formed on <span class="hlt">steels</span> in the first months of atmospheric exposure</span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>Antunes Renato Altobelli; Costa Isolda; Faria Dalva Lúcia Araújo de</p> <p>2003-01-01</p> <p>The <span class="hlt">corrosion</span> products of carbon <span class="hlt">steel</span> and weathering <span class="hlt">steel</span> exposed to three different types of atmospheres, at times ranging from one to three months, have been identified. The <span class="hlt">steels</span> were exposed in an industrial site, an urban site (São Paulo City, Brazil), and a humid site. The effect of the <span class="hlt">steel</span> type on the <span class="hlt">corrosion</span> products formed in the early stages of atmospheric <span class="hlt">corrosion</span> has been evaluated. The <span class="hlt">corrosion</span> products formed at the various exposure locations were characterized by Raman...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=131407','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=131407"><span id="translatedtitle">Crevice <span class="hlt">corrosion</span> repassivation temperatures of highly alloyed stainless <span class="hlt">steels</span></span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Valen, S.; Gartland, P.O. [SINTEF Corrosion Center, Trondheim (Norway)</p> <p>1995-10-01</p> <p>An investigation was conducted to study the repassivation temperature of a highly alloyed austenitic (UNS S31254) and of a highly alloyed duplex (UNS S32750) stainless <span class="hlt">steel</span> (SS). When initiated at a high temperature, repassivation occurred at a temperature level significantly lower than normally associated with initiation of crevice <span class="hlt">corrosion</span>. Experimental results combined with computer modeling of crevice <span class="hlt">corrosion</span> explored the mechanistic aspects. In this respect, the similarity between the hysteresis observed by cyclic polarization and cyclic temperature tests was emphasized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=od______1271::3deb12d53f019ca5d01fbaae3e43ef2c','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=od______1271::3deb12d53f019ca5d01fbaae3e43ef2c"><span id="translatedtitle">Influence of anions on the <span class="hlt">corrosion</span> of high speed <span class="hlt">steel</span></span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>Brett, C. M. A.; Melo, P. I. C.</p> <p>1997-01-01</p> <p><span class="hlt">Corrosion</span> potential measurements, voltammetric techniques and electrochemical impedance have been used to evaluate the <span class="hlt">corrosion</span> resistance of M2 high speed <span class="hlt">steel</span> in aqueous solutions containing chloride, bromide, iodide, nitrate, sulfate and perchlorate salts of sodium and potassium of varying concentration. The influence of changing the cation was found to be small and an order of anion aggressivity was established as: sulfate>chloride>bromide>perchlorate>iodide>nitrate. The data obtained a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=21565187','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=21565187"><span id="translatedtitle">Ni-W coatings electrodeposited on carbon <span class="hlt">steel</span>: Chemical composition, mechanical properties and <span class="hlt">corrosion</span> resistance</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Arganaraz, M.P. Quiroga; Ribotta, S.B. [INQUINOA-CONICET, Instituto de Quimica Fisica, Facultad de Bioquimica, Quimica y Farmacia, Universidad Nacional de Tucuman, Ayacucho 471, (4000) San Miguel de Tucuman (Argentina); Folquer, M.E., E-mail: mefolquer@fbqf.unt.edu.ar [INQUINOA-CONICET, Instituto de Quimica Fisica, Facultad de Bioquimica, Quimica y Farmacia, Universidad Nacional de Tucuman, Ayacucho 471, (4000) San Miguel de Tucuman (Argentina); Gassa, L.M.; Benitez, G.; Vela, M.E.; Salvarezza, R.C. [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas (INIFTA), Universidad Nacional de La Plata-CONICET, Suc. 4, C.C. 16, (1900) La Plata (Argentina)</p> <p>2011-07-01</p> <p>Highlights: > Hard, ductile and adherent nanostructured Ni-W coatings on carbon <span class="hlt">steel</span>. > New procedures for achieving deposits by current pulse techniques. > Current pulse frequency was the dominant factor to define coating characteristics. > Ni-W coatings <span class="hlt">protect</span> the carbon <span class="hlt">steel</span> from <span class="hlt">corrosion</span> induced by sulphate anions. - Abstract: Hard, ductile and adherent nanostructured Ni-W coatings were electrodeposited on carbon <span class="hlt">steel</span> from electrolyte solutions containing sodium tungstate, nickel sulfate and sodium citrate, using different current pulse programs. Current pulse frequency was the dominant factor to define chemical composition, grain size, thickness and hardness. According to the electrodeposition conditions the deposited coatings showed 15-30 at% W, the grain size ranged from 65 to 140 nm, and the hardness varied from 650 to 850 Hv. Tungsten carbide also present in the coating contributed to its hardness. The <span class="hlt">corrosion</span> resistance of the Ni-W coated <span class="hlt">steel</span> was tested by potentiodynamic polarization in a neutral medium containing sulphate ions. The Ni-W coating <span class="hlt">protected</span> the carbon <span class="hlt">steel</span> from localized <span class="hlt">corrosion</span> induced by sulphate anions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:43042995','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:43042995"><span id="translatedtitle">Ni-W coatings electrodeposited on carbon <span class="hlt">steel</span>: Chemical composition, mechanical properties and <span class="hlt">corrosion</span> resistance</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Highlights: ? Hard, ductile and adherent nanostructured Ni-W coatings on carbon <span class="hlt">steel</span>. ? New procedures for achieving deposits by current pulse techniques. ? Current pulse frequency was the dominant factor to define coating characteristics. ? Ni-W coatings <span class="hlt">protect</span> the carbon <span class="hlt">steel</span> from <span class="hlt">corrosion</span> induced by sulphate anions. - Abstract: Hard, ductile and adherent nanostructured Ni-W coatings were electrodeposited on carbon <span class="hlt">steel</span> from electrolyte solutions containing sodium tungstate, nickel sulfate and sodium citrate, using different current pulse programs. Current pulse frequency was the dominant factor to define chemical composition, grain size, thickness and hardness. According to the electrodeposition conditions the deposited coatings showed 15-30 at% W, the grain size ranged from 65 to 140 nm, and the hardness varied from 650 to 850 Hv. Tungsten carbide also present in the coating contributed to its hardness. The <span class="hlt">corrosion</span> resistance of the Ni-W coated <span class="hlt">steel</span> was tested by potentiodynamic polarization in a neutral medium containing sulphate ions. The Ni-W coating <span class="hlt">protected</span> the carbon <span class="hlt">steel</span> from localized <span class="hlt">corrosion</span> induced by sulphate anions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=22222766','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=22222766"><span id="translatedtitle">Flow accelerated <span class="hlt">corrosion</span> of carbon <span class="hlt">steel</span> piping in nuclear power plants</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Kim, Sang Hyun</p> <p>2006-02-15</p> <p>Flow accelerated <span class="hlt">corrosion</span> (FAC) is a process whereby the normally <span class="hlt">protective</span> oxide layer on carbon or low alloy <span class="hlt">steel</span> dissolved into a stream of flowing water resulting in increasing the <span class="hlt">corrosion</span> rate. Major influencing factors that affect the FAC are flow velocity, temperature, pH, dissolved oxygen concentration, and <span class="hlt">steel</span> composition. The experimental study described in this paper was focused on evaluating the FAC behavior of carbon <span class="hlt">steel</span> according to environment conditions. Feasibility tests for the mitigation method against the FAC were also carried out with controlling the water chemistry and with applying the magnetic field. A high temperature rotating cylinder electrode (HTRCE) and a water chemistry control system was developed to perform the electrochemical test in high temperature water environments. The main design concept of HTRCE is to assure stable operation of working electrode in a severe environment, to insulate electrode housing except working electrode surface against external fluid, and to extract <span class="hlt">corrosion</span> parameter from the rotating cylinder to outside of the autoclave safely. The electrochemical <span class="hlt">corrosion</span> potential (ECP) and current density were measured as a function of temperature and rotating speed using polarization monitoring. ECP values dropped at a rate of -1.51 mV/.deg. C above 150 .deg. C, which may be come from the formation of magnetite on the <span class="hlt">steel</span> surface. With increasing rotation of the RCE, the ECP shifted upward in all temperature ranges. This shift may be attributed to the diffusion enhancement of the oxidizing agents in the rapidly flowing of fluid. From the velocity exponent of the cathodic half-cell current density on the <span class="hlt">steel</span> surface, it was evident that a mass transfer process first dominated the <span class="hlt">corrosion</span> reaction at 150 .deg. C, and then an activation process partly controlled the <span class="hlt">corrosion</span> kinetics with increasing temperature. From the results of <span class="hlt">corrosion</span> experiment at high temperature water, HTRCE has been proved as an effective device to evaluate the velocity sensitivity of <span class="hlt">corrosion</span> reaction in high temperature water. An electrochemical analysis was performed to evaluate the effects of fluid flow and dissolved oxygen on the <span class="hlt">corrosion</span> behavior of carbon <span class="hlt">steel</span> and to correlate electrochemical aspect with the flow accelerated <span class="hlt">corrosion</span> rate. In neutral pH water containing 2 ppb oxygen, the ECP and <span class="hlt">corrosion</span> current density were increased with rotation of electrode. <span class="hlt">Corrosion</span> current density showed similar tendency with a wall shear stress on the surface of electrode due to the fluid flow. The wall shear stress might cause a decrease in the mass transfer boundary layer thickness resulting in increase in the rate of the <span class="hlt">corrosion</span> reaction due to faster diffusion of the soluble <span class="hlt">corrosion</span> product into the bulk solution. When the oxygen concentration exceeds a threshold concentration, the cathodic current previously supplied by the hydrogen evolution reaction is substituted by an equivalent reaction due to oxygen reduction. Thus, the ECP increases up to the range of hematite which has a very low solubility and electric conductivity. The hematite formation would lead to inhibit flow accelerated <span class="hlt">corrosion</span>. The effects of a magnetic field on the FAC behavior of a low alloy <span class="hlt">steel</span> were evaluated to develop a method to mitigate against feeder wall thinning. A magnet-attached rotating cylinder electrode and piping <span class="hlt">steel</span> covered with simulated oxide film were used in potentiodynamic test and erosion test to determine the magnetic effect on electrochemical and erosional aspect of the oxide layer, respectively. An Electrochemical <span class="hlt">corrosion</span> reaction was active in the magnetic field because the local mass transfer rate was increased by the magnetohydrodynamic force generated by a coupling of the electric and magnetic field. However, the magnetic field effect decreased with increasing temperature and rotation velocity. Those might be come from the facts that the thickness of the diffusion layer decreased with rotating velocity and the diffusion constant increased with increasing temperatu</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:45043721','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:45043721"><span id="translatedtitle">Flow accelerated <span class="hlt">corrosion</span> of carbon <span class="hlt">steel</span> piping in nuclear power plants</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Flow accelerated <span class="hlt">corrosion</span> (FAC) is a process whereby the normally <span class="hlt">protective</span> oxide layer on carbon or low alloy <span class="hlt">steel</span> dissolved into a stream of flowing water resulting in increasing the <span class="hlt">corrosion</span> rate. Major influencing factors that affect the FAC are flow velocity, temperature, pH, dissolved oxygen concentration, and <span class="hlt">steel</span> composition. The experimental study described in this paper was focused on evaluating the FAC behavior of carbon <span class="hlt">steel</span> according to environment conditions. Feasibility tests for the mitigation method against the FAC were also carried out with controlling the water chemistry and with applying the magnetic field. A high temperature rotating cylinder electrode (HTRCE) and a water chemistry control system was developed to perform the electrochemical test in high temperature water environments. The main design concept of HTRCE is to assure stable operation of working electrode in a severe environment, to insulate electrode housing except working electrode surface against external fluid, and to extract <span class="hlt">corrosion</span> parameter from the rotating cylinder to outside of the autoclave safely. The electrochemical <span class="hlt">corrosion</span> potential (ECP) and current density were measured as a function of temperature and rotating speed using polarization monitoring. ECP values dropped at a rate of -1.51 mV/.deg. C above 150 .deg. C, which may be come from the formation of magnetite on the <span class="hlt">steel</span> surface. With increasing rotation of the RCE, the ECP shifted upward in all temperature ranges. This shift may be attributed to the diffusion enhancement of the oxidizing agents in the rapidly flowing of fluid. From the velocity exponent of the cathodic half-cell current density on the <span class="hlt">steel</span> surface, it was evident that a mass transfer process first dominated the <span class="hlt">corrosion</span> reaction at 150 .deg. C, and then an activation process partly controlled the <span class="hlt">corrosion</span> kinetics with increasing temperature. From the results of <span class="hlt">corrosion</span> experiment at high temperature water, HTRCE has been proved as an effective device to evaluate the velocity sensitivity of <span class="hlt">corrosion</span> reaction in high temperature water. An electrochemical analysis was performed to evaluate the effects of fluid flow and dissolved oxygen on the <span class="hlt">corrosion</span> behavior of carbon <span class="hlt">steel</span> and to correlate electrochemical aspect with the flow accelerated <span class="hlt">corrosion</span> rate. In neutral pH water containing 2 ppb oxygen, the ECP and <span class="hlt">corrosion</span> current density were increased with rotation of electrode. <span class="hlt">Corrosion</span> current density showed similar tendency with a wall shear stress on the surface of electrode due to the fluid flow. The wall shear stress might cause a decrease in the mass transfer boundary layer thickness resulting in increase in the rate of the <span class="hlt">corrosion</span> reaction due to faster diffusion of the soluble <span class="hlt">corrosion</span> product into the bulk solution. When the oxygen concentration exceeds a threshold concentration, the cathodic current previously supplied by the hydrogen evolution reaction is substituted by an equivalent reaction due to oxygen reduction. Thus, the ECP increases up to the range of hematite which has a very low solubility and electric conductivity. The hematite formation would lead to inhibit flow accelerated <span class="hlt">corrosion</span>. The effects of a magnetic field on the FAC behavior of a low alloy <span class="hlt">steel</span> were evaluated to develop a method to mitigate against feeder wall thinning. A magnet-attached rotating cylinder electrode and piping <span class="hlt">steel</span> covered with simulated oxide film were used in potentiodynamic test and erosion test to determine the magnetic effect on electrochemical and erosional aspect of the oxide layer, respectively. An Electrochemical <span class="hlt">corrosion</span> reaction was active in the magnetic field because the local mass transfer rate was increased by the magnetohydrodynamic force generated by a coupling of the electric and magnetic field. However, the magnetic field effect decreased with increasing temperature and rotation velocity. Those might be come from the facts that the thickness of the diffusion layer decreased with rotating velocity and the diffusion constant increased with increasing temperatu</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:21037068','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:21037068"><span id="translatedtitle">Long-term <span class="hlt">corrosion</span> behavior of cathodicly <span class="hlt">protected</span> cask materials</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The concept of a canister based on the principle of cathodic <span class="hlt">protection</span> has been introduced. The main points for this concept are: nonself-shielding canisters require a radiation <span class="hlt">protection</span> jacket during the operational stage of the repository; cost-efficient material for radiation <span class="hlt">protection</span> is nodular cast iron; and multilayered canister consisting of materials which become successively more noble towards the inner shells has been found to be too large and too heavy for a repository. This problem has been overcome now by a new and cost-efficient production method. This is accomplished by immersing a tube made of stainless <span class="hlt">steel</span> in molten GGG 40.3 at a defined temperature and letting them cool together. Dimensions and weight now meet the requirements of the repository. In case of an accident, that is intrusion of brine into the repository and contact with the canister, <span class="hlt">corrosion</span> will start uniformly at the outer cast iron package. This package is sufficiently designed not to be used up in a projected term of 500 years. If, nonetheless, the cast iron jacket should rupture by means of <span class="hlt">corrosion</span> or mechanical damage, a shortcircuit cell will form with the cast iron being the anode and the stainless <span class="hlt">steel</span> acting as the cathode. The testing of welded large-scale integral structures, which can be regarded as mock-ups of a canister section, is in progress since March 1984 to demonstrate the feasibility of this container concept. Two such bodies are immersed in brine at 100 degree C. Examinations with the very sensitive liquid penetration test fluorescent proved both bodies to be free of incipient cracks or local <span class="hlt">corrosion</span> in the area of the weld seams</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ijettjournal.org/volume-8/number-3/IJETT-V8P222.pdf','DOAJ-ART-EN'); return false;" href="http://ijettjournal.org/volume-8/number-3/IJETT-V8P222.pdf"><span id="translatedtitle">Efficiency of <span class="hlt">Corrosion</span> Inhibitors on Cathodic <span class="hlt">Protection</span> System</span></a></p> <p><a target="_blank" href="http://www.doaj.org/doaj?func=searchArticles">Directory of Open Access Journals (Sweden)</a></p> <p>Tobinson Briggs</p> <p>2014-02-01</p> <p>Full Text Available This study is on experiment being carried out to determine the efficiency of in inhibitors on catholically <span class="hlt">protected</span> medium carbon <span class="hlt">steel</span> in sea water in Bonny and Ogbokoro in the Niger Delta region of Nigeria. The experiment was conducted using the total immersion technique in a non-flowing media containing sea water inhibited with potassium dichromate, sodium nitrate, ECIO21A, sarvor CK 368, and Kurizets 636. In the course of this research work, Cathodically <span class="hlt">protected</span> and unprotected medium carbon <span class="hlt">steel</span> were totally immersed in seawater containing the aforementioned inhibitors differently. Their weight loss, <span class="hlt">corrosion</span> rate, pH value and <span class="hlt">corrosion</span> potentials were determined at intervals of 72 hours, over 2016 hours the test lasted. The results obtained shows that inhibitor EC1021A has efficiency of 79.8%, other results are as follows: Kurizet S.636, 77%, savor CK368, 43%, potassium dichromate, 35% and sodium nitrate, 1.88%. It was concluded that EC1021A is the most efficient inhibitor, under a non-flow system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=22233866','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=22233866"><span id="translatedtitle">Pitting <span class="hlt">corrosion</span> detection in stainless <span class="hlt">steels</span> using ultrasounds; Deteccion de la <span class="hlt">corrosion</span> por picadura en aceros inoxidables empleando ultrasonidos</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Rodriguez, C.; Biezma, M. V.</p> <p>2014-04-01</p> <p>Passive metallic systems are able to develop in a spontaneous way a <span class="hlt">protective</span> layer on the metallic surface that offers excellent <span class="hlt">corrosion</span> resistance since really in a physical barrier for the reaction with the environment. However, some factors can break locally this layer, promoting one of the most insidious attack, pitting <span class="hlt">corrosion</span>, which produces local chemical conditions that favouring the <span class="hlt">corrosive</span> process causing defects in the material, as externals and internals ones, with a random distribution on the metal surface. In this work, ultrasounds non destructive technique has been employed using as variable the maximum amplitude of the back wall echo in order to detect this type of attack. The material employed is an austenitic stainless <span class="hlt">steel</span> AISI 304, wherein appear several defectology distributions as superficial such as depths simulating pits. (Author)</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392013000600035&lang=en','SCIELO-EN'); return false;" href="http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392013000600035&lang=en"><span id="translatedtitle"><span class="hlt">Steel</span> <span class="hlt">corrosion</span> assessment by electrochemical impedance on metakaolin blended mortars</span></a></p> <p><a target="_blank" href="http://www.scielo.org/php/index.php?lang=en">Scientific Electronic Library Online (English)</a></p> <p>Víctor, Triana; Juan, Lizarazo-Marriaga; Jhon Olaya, Flórez.</p> <p>2013-12-01</p> <p>Full Text Available Since <span class="hlt">Corrosion</span> of reinforcing <span class="hlt">steel</span> in concrete is the cause of major economic losses, Portland cement has been traditionally replaced by cements blended with pozzalanic materials, most of which have been found to reduce the <span class="hlt">corrosion</span> of <span class="hlt">steel</span>. This paper shows the results of an experimental resear [...] ch aimed to investigate the <span class="hlt">corrosion</span> of reinforcement in mortar using electrochemical impedance spectroscopy (EIS). For this, concrete laboratory samples containing a 0.0055 m <span class="hlt">steel</span> bar and prepared with just ordinary Portland cement (OPC) and metakaolin at a replacement level of 20% were analyzed. In order to accelerate the <span class="hlt">steel</span> <span class="hlt">corrosion</span> process, all the samples were kept in a 3% NaCl solution and a constant anodic electrical potential was applied. Variations in the water to cementitious material ratio (0.5 and 0.6) and metakaolin proportion were analyzed, while the cementitious material to sand ratio was kept constant at 1:2.25 in all of the specimens. The results showed a reduction in <span class="hlt">corrosion</span> rates when metakaolin was used as a blending admixture, especially at water to cementitious material ratio of 0.5.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:14788306','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:14788306"><span id="translatedtitle"><span class="hlt">Corrosion</span> <span class="hlt">protection</span> system for nuclear power plant</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>A cathodic <span class="hlt">corrosion</span> <span class="hlt">protection</span> system for a nuclear power plant which employs an ion tank adjacent the main fresh water feed pipe leading to the steam generator to treat water from the main feed pipe and then return the treated water to the main feed pipe to form a <span class="hlt">corrosion</span> <span class="hlt">protecting</span> alkaline layer on surfaces of the main feed pipe and the secondary side of the steam generator. The ion tank receives measured amounts of hydrazine to render the water therein substantially conductive and contains ionizable metal anodes which release free metal ions as electric current flows between the anodes and a cathode connection on an ion tank outlet pipe near the main feed water pipe</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:27043571','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:27043571"><span id="translatedtitle">Microbial <span class="hlt">corrosion</span> of high alloy <span class="hlt">steels</span> in natural sea water</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The paper deals with an investigation into regularities of settlement and potential impact of microbial forms on the <span class="hlt">corrosion</span> of 12Kh18N10T stainless <span class="hlt">steel</span> depending on its microstructure. It is shown that inhomogeneity of the morphorological composition and quantitative distribution of microorganisms on the surface of alloyed <span class="hlt">steels</span> is caused by the selectivity of bacterial cells settlement on the substrate structural elements. The <span class="hlt">corrosion</span> destruction at microscopic level primarily starts in the zones of microorganism concentration. 19 refs.; 3 figs.; 2 tabs</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://lejpt.academicdirect.org/A27/120_130.pdf','DOAJ-ART-EN'); return false;" href="http://lejpt.academicdirect.org/A27/120_130.pdf"><span id="translatedtitle"><span class="hlt">Corrosion</span> behaviour of some conventional stainless <span class="hlt">steels</span> in electrolyzing process</span></a></p> <p><a target="_blank" href="http://www.doaj.org/doaj?func=searchArticles">Directory of Open Access Journals (Sweden)</a></p> <p>Amal NASSAR</p> <p>2015-12-01</p> <p>Full Text Available In this study, attempts were made to increase the amount of hydrogen generated from the water electrolysis process. Some conventional stainless <span class="hlt">steels</span> (316; 409; 410 and 430 were used as anode and cathode in electrolysis process. Further study was carried out on the <span class="hlt">corrosion</span> trend in all the investigated metals. It is observed that the electrode material can effect on the amount of hydrogen generate by electrolyzing process and metal composition of the stainless <span class="hlt">steels</span> effects on the rate of <span class="hlt">corrosion</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:37078964','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:37078964"><span id="translatedtitle"><span class="hlt">Corrosion</span> of 316L stainless <span class="hlt">steels</span> MAVL wastes containers</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The long lived and medium activity wastes are conditioned or could be re-conditioned in primary drums of 316L stainless <span class="hlt">steels</span>. In the framework of wastes storage, these drums will be placed in concrete containers; each containers would contain one or more drums. This document recalls global information on the <span class="hlt">corrosion</span> of stainless <span class="hlt">steels</span>, analyzes specific conditions bond to the drums conditioning in concrete containers and the nature of the wastes, and details the consequences on the possible risks of external and internal <span class="hlt">corrosion</span> of the drums. (A.L.B.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=doajarticles::329853707bff26f7a17210dc78a3cdd8','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=doajarticles::329853707bff26f7a17210dc78a3cdd8"><span id="translatedtitle">A Novel Carbon <span class="hlt">Steel</span> Pipe <span class="hlt">Protection</span> Based on Radial Basis Function Neural Network</span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>Sami A. Ajeel</p> <p>2010-01-01</p> <p>Problem statement: The cost due to <span class="hlt">corrosion</span> Damage have estimated to be 3-4% of their gross national product which significantly Countries problem around the world. Approach: In this study, a novel carbon <span class="hlt">steel</span> pipe <span class="hlt">protection</span> based on RBFNN was proposed. The RBFNN used to predict the minimum current density required in impressed current cathodic <span class="hlt">protection</span> to <span class="hlt">protect</span> low carbon <span class="hlt">steel</span> pipe. Learning data was performed by using a 30 samples test with different concentration C%, temperature T,...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:38068198','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:38068198"><span id="translatedtitle"><span class="hlt">Corrosion</span> of a carbon <span class="hlt">steel</span> in simulated liquid nuclear wastes</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>This work is part of a collaboration agreement between CNEA (National Atomic Energy Commission of Argentina) and USDOE (Department of Energy of the United States of America), entitled 'Tank <span class="hlt">Corrosion</span> Chemistry Cooperation', to study the <span class="hlt">corrosion</span> behavior of carbon <span class="hlt">steel</span> A537 class 1 in different simulated non-radioactive wastes in order to establish the safety concentration limits of the tank waste chemistry at Hanford site (Richland-US). Liquid high level nuclear wastes are stored in tanks made of carbon <span class="hlt">steel</span> A537 (ASTM nomenclature) that were designed for a service life of 20 to 50 years. A thickness reduction of some tank walls, due to <span class="hlt">corrosion</span> processes, was detected at Hanford site, beyond the existing predicted values. Two year long-term immersion tests were started using non radioactive simulated liquid nuclear waste solutions at 40 C degrees. This work extends throughout the first year of immersion. The simulated solutions consist basically in combinations of the 10 most <span class="hlt">corrosion</span> significant chemical components: 5 main components (NaNO3, NaCl, NaF, NaNO2 and NaOH) at three concentration levels and 5 secondary components at two concentration levels. Measurements of the general <span class="hlt">corrosion</span> rate with time were performed for carbon <span class="hlt">steel</span> coupons, both immersed in the solutions and in the vapor phases, using weight loss and electrochemistry impedance spectroscopy techniques. Optic and scanning electron microscopy examination, analysis of U-bend samples and <span class="hlt">corrosion</span> potential measurements, were also done. Localized <span class="hlt">corrosion</span> susceptibility (pitting and crevice <span class="hlt">corrosion</span>) was assessed in isolated short-term tests by means of cyclic potentiodynamic polarization curves. The effect of the simulated waste composition on the <span class="hlt">corrosion</span> behavior of A537 <span class="hlt">steel</span> was studied based on statistical analyses. The Surface Response Model could be successfully applied to the statistical analysis of the A537 <span class="hlt">steel</span> <span class="hlt">corrosion</span> in the studied solutions. General <span class="hlt">corrosion</span> was not significant for A537 carbon <span class="hlt">steel</span> in the concentration range of the solutions studied (pH 10-13) at 40 C degrees. The highest calculated <span class="hlt">corrosion</span> rate for immersed samples, using the electrochemical impedance spectroscopy techniques, was 25 ?m/yr, while the highest calculated <span class="hlt">corrosion</span> rate for vapor phase coupons, using weight-loss measurements, was 51 ?m/yr. On the contrary, it was found that A537 carbon <span class="hlt">steel</span> was highly susceptible to localized attack, due to pitting and crevice <span class="hlt">corrosion</span>, in the solutions and at the temperature studied. The highest penetration rates produced by pitting attack, measured by optical microscopy examination after 11 month immersion, were 0.3 mm/yr and 0.4 mm/yr for the immersed and the vapor phase coupons respectively. The highest penetration rate produced by crevice <span class="hlt">corrosion</span> on the immersed coupons, measured by optical microscopy examination after 11 month immersion, was 1,1 mm/yr. Stress <span class="hlt">corrosion</span> cracking signs were not observed after 11 month immersion on the U-bend coupons. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:43125296','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:43125296"><span id="translatedtitle">Resistance of Cementitious Binders to Chloride Induced <span class="hlt">Corrosion</span> of Embedded <span class="hlt">Steel</span> by Electrochemical and Microstructural Studies</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The high alkaline property in the concrete pore solution <span class="hlt">protects</span> the embedded <span class="hlt">steel</span> in concrete from <span class="hlt">corrosion</span> due to aggressive ions attack. However, a continuous supply of those ions, in particular, chlorides altogether with a pH fall in electrochemical reaction on the <span class="hlt">steel</span> surface eventually depassivate the <span class="hlt">steel</span> to corrode. To mitigate chloride-induced <span class="hlt">corrosion</span> in concrete structures, finely grained mineral admixtures, for example, pulverized fuel ash (PFA), ground granulated blast furnace slag (GGBS) and silica fume (SF) have been often advised to replace ordinary Portland cement (OPC) partially as binder. A consistent assessment of those partial replacements has been rarely performed with respect to the resistance of each binder to <span class="hlt">corrosion</span>, although the studies for each binder were extensively looked into in a way of measuring the <span class="hlt">corrosion</span> rate, influence of microstructure or chemistry of chlorides ions with cement hydrations. The paper studies the behavior of <span class="hlt">steel</span> <span class="hlt">corrosion</span>, chloride transport, pore structure and buffering capacity of those cementitious binders. The <span class="hlt">corrosion</span> rate of <span class="hlt">steel</span> in mortars of OPC, 30% PFA, 60% GGBS and 10% SF respectively, with chloride in cast ranging from 0.0 to 3.0% by weight of binder was measured at 7, 28 and 150 days to determine the chloride threshold level and the rate of <span class="hlt">corrosion</span> propagation, using the anodic polarization technique. Mercury intrusion porosimetry was also applied to cement pastes of each binder at 7 and 28 days to ensure the development of pore structure. Finally, the release rate of bound chlorides (I.e. buffering capacity) was measured at 150 days. The chloride threshold level was determined assuming that the <span class="hlt">corrosion</span> rate is beyond 1-2 mA/m3 at <span class="hlt">corrosion</span> and the order of the level was OPC > 10% SF > 60% GGBS > 30% PFA. Mercury intrusion porosimetry showed that 10% SF paste produced the most dense pore structure, followed by 60% GGBS, 30% PFA and OPC pastes, respectively. It was found that OPC itself is beneficial in resisting to <span class="hlt">corrosion</span> initiation, but use of pozzolanic materials as binders shows more resistance to chloride transport into concrete, thus delay the onset of <span class="hlt">corrosion</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:10481743','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:10481743"><span id="translatedtitle"><span class="hlt">Corrosion</span> in austenitic stainless <span class="hlt">steels</span> (Cr-Ni alloy S.S.) under chemical conditions</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Various types of <span class="hlt">corrosion</span> such as intergranular, pitting, crevice, galvanic <span class="hlt">corrosion</span> and stress <span class="hlt">corrosion</span> cracking occurring in austenitic stainless <span class="hlt">steels</span> under varying chemical conditions are explained. <span class="hlt">Corrosion</span> by acids, bases and inorganic compounds is also explained. Nominal composition and special features of different types of AISI <span class="hlt">steels</span> are listed. (A.K.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:17058581','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:17058581"><span id="translatedtitle"><span class="hlt">Corrosion</span> resistance of niobium-to-<span class="hlt">steel</span> welded joints in boiling nitric acid</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p><span class="hlt">Corrosion</span> resistance of niobium with stell welded joints in boiling nitric acid is studied by melting of <span class="hlt">steel</span> only. It is shown that it corresponds to the 12Kh18N10T <span class="hlt">steel</span> resistance and is determined by general <span class="hlt">corrosion</span>. At the presence of interlayer of intermetallic compounds in the niobium with <span class="hlt">steel</span> contact zone the <span class="hlt">corrosion</span> resistance of joints decreases</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title21-vol3/pdf/CFR-2010-title21-vol3-sec178-3300.pdf','SCIGOV-EN'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title21-vol3/pdf/CFR-2010-title21-vol3-sec178-3300.pdf"><span id="translatedtitle">21 CFR 178.3300 - <span class="hlt">Corrosion</span> inhibitors used for <span class="hlt">steel</span> or tinplate.</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p></p> <p>2010-04-01</p> <p>... 21 Food and Drugs 3 2010-04-01 2009-04-01 true <span class="hlt">Corrosion</span> inhibitors used for <span class="hlt">steel</span> or tinplate... AIDS, AND SANITIZERS Certain Adjuvants and Production Aids § 178.3300 <span class="hlt">Corrosion</span> inhibitors used for <span class="hlt">steel</span> or tinplate. <span class="hlt">Corrosion</span> inhibitors may be safely used for <span class="hlt">steel</span> or tinplate intended for use in,...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997PhDT.......220L','SCIGOV-EN'); return false;" href="http://adsabs.harvard.edu/abs/1997PhDT.......220L"><span id="translatedtitle">The electrochemical <span class="hlt">corrosion</span> behavior of low-carbon <span class="hlt">steel</span> in simulated Yucca Mountain repository environments</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Lian, Tiangan</p> <p></p> <p>The <span class="hlt">corrosion</span> of nuclear waste container materials in possible concentrated underground environments is one of the major concerns in Yucca Mountain repository project. Low carbon <span class="hlt">steel</span> (LCS) is considered an optional material to serve as a <span class="hlt">corrosion</span> allowance layer. AISI 1016 low carbon <span class="hlt">steel</span> was investigated in concentrated J-13 ground waters. The electrochemical behavior of LCS was studied by monitoring <span class="hlt">corrosion</span> potential behavior, measuring polarization resistance and conducting anodic potentiodynamic polarization and cyclic polarization tests. LCS showed excellent resistance against general <span class="hlt">corrosion</span> in J-13 waters under de-aerated conditions, with the measured <span class="hlt">corrosion</span> rates at 25sp° and 90sp°C were less than 0.28 mpy. The temperature, precipitation and overall concentration effects on <span class="hlt">corrosion</span> rate were minimal under de-aerating conditions. Under aerated conditions, the dissolved oxygen significantly increased <span class="hlt">corrosion</span> rate of LCS in the J-13 water with low concentration and temperature. <span class="hlt">Corrosion</span> rate reached 5.5 mpy in aerated 10X J-13 water at 25sp°C. <span class="hlt">Corrosion</span> rate of LCS decreased in aerated J-13 waters with increasing temperature or concentration. With limitation of solubility, concentration overall species in J-13 water up to 1000X did not increase <span class="hlt">corrosion</span> rate or tendency of localized <span class="hlt">corrosion</span>. Resistance to pitting <span class="hlt">corrosion</span> varies with presence of aggressive Clsp- ions, oxidizer, inhibitors and precipitates. With heavy precipitates in overall concentrated J-13 waters at 90sp°C, measured pitting and <span class="hlt">protection</span> potentials were increased significantly. Presence of dissolved oxygen or higher Clsp- fraction decreased Esbpit, and significantly decreased Esbprot as well. However, 1000X Clsp- J-13 water formed passive film on LCS at 25sp°C. Addition of Fesp{3+} significantly increased pitting and crevice <span class="hlt">corrosion</span> tendency, because adding FeClsb3 removed inhibitor and passivator anions from aerated J-13 waters during the solution preparation. With presence of Fesp{3+} or depletion of inhibitor/passivator anions, pitting <span class="hlt">corrosion</span> was observed on LCS shortly exposed in J-13 Fesp{3+} waters. The pitting is believed to initiated under the iron hydroxides/oxides deposits. Higher temperature initiated pits at a lower potential and shorter induction time. Dissolved silicate ions were found an effective inhibitor in J-13 waters to reduce <span class="hlt">corrosion</span> rate and prevent localized <span class="hlt">corrosion</span>. Formation of stable metal silicates assures the inhibitory effects of precipitates at higher temperatures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:46027981','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:46027981"><span id="translatedtitle">Experimental studies of 2-pyridinecarbonitrile as <span class="hlt">corrosion</span> inhibitor for mild <span class="hlt">steel</span> in hydrochloric acid solution</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Highlights: • The <span class="hlt">corrosion</span> effect of inhibitor was studied in 0.1 mol L?1 HCl on mild <span class="hlt">steel</span>. • The inhibitor efficiency increases with increase in the concentration of inhibitor. • SEM micrographs showed that the inhibitor has a good <span class="hlt">protective</span> film on the metal surface. - Abstract: The effect of 2-Pyridinecarbonitrile (2-PCN) was studied on mild <span class="hlt">steel</span> (MS) <span class="hlt">corrosion</span> in 0.1 mol L?1 HCl by electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR) and potentiodynamic polarization measurements. The surface morphologies of the MS were investigated in the inhibitor-free and in the presence of 10 mmol L?1 2-PCN containing <span class="hlt">corrosive</span> media, at 120 h exposure period by scanning electron microscopy (SEM). The mechanism of adsorption was determined from the potential of zero charge (Epzc). 2-PCN adsorption on the MS surface obeyed the isotherm of Langmuir and the thermodynamic parameters Kads; ?Gads° were also calculated and discussed</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999ApSS..148..171A','SCIGOV-EN'); return false;" href="http://adsabs.harvard.edu/abs/1999ApSS..148..171A"><span id="translatedtitle">Characterization and <span class="hlt">corrosion</span> studies of laser-melted carbon <span class="hlt">steel</span> surfaces</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Agudelo, A. C.; Gancedo, J. R.; Marco, J. F.; Creus, M. F.; Gallego-Lluesma, E.; Desimoni, J.; Mercader, R. C.</p> <p>1999-07-01</p> <p>We have observed by conversion electron Mössbauer spectroscopy (CEMS) that the irradiation of carbon <span class="hlt">steel</span> surfaces with an industrial CO 2 laser, under different experimental conditions, brings about the formation of ?-Fe 2O 3, Fe 3O 4 and Fe 1- xO. The larger beam-surface interaction times favour the formation of greater amounts of Fe 3+ oxides (mainly ?-Fe 2O 3) within the depth that can be probed by CEMS (?300 nm). A model based on the numerical solution of the heat-diffusion equation gives evidence that the oxidation processes are mainly dictated by the time at which the metal remains at temperatures higher than the melting point. In addition, the samples have been subjected to wet-dry <span class="hlt">corrosion</span> cycles in SO 2-polluted atmospheres and monitored by CEMS and weight gain. The oxide layer reduces noticeably the <span class="hlt">corrosion</span> rate of <span class="hlt">steel</span> against <span class="hlt">corrosion</span>. This <span class="hlt">protection</span> is related to the composition of the oxidation layer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/15278311','SCIGOV-EN'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/15278311"><span id="translatedtitle">Inhibiting mild <span class="hlt">steel</span> <span class="hlt">corrosion</span> from sulfate-reducing and iron-oxidizing bacteria using gramicidin-S-producing biofilms.</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Zuo, Rongjun; Wood, Thomas K</p> <p>2004-11-01</p> <p>A gramicidin-S-producing Bacillus brevis 18-3 biofilm was shown to reduce <span class="hlt">corrosion</span> rates of mild <span class="hlt">steel</span> by inhibiting both the sulfate-reducing bacterium Desulfosporosinus orientis and the iron-oxidizing bacterium Leptothrix discophora SP-6. When L. discophora SP-6 was introduced along with D. orientis to a non-antimicrobial-producing biofilm control, Paenibacillus polymyxa ATCC 10401, a <span class="hlt">corrosive</span> synergy was created and mild <span class="hlt">steel</span> coupons underwent more severe <span class="hlt">corrosion</span> than when only D. orientis was present, showing a 2.3-fold increase via electrochemical impedance spectroscopy (EIS) and a 1.8-fold difference via mass-loss measurements. However, when a gramicidin-S-producing, <span class="hlt">protective</span> B. brevis 18-3 biofilm was established on mild <span class="hlt">steel</span>, the metal coupons were <span class="hlt">protected</span> against the simultaneous attack of D. orientis and L. discophora SP-6. EIS data showed that the <span class="hlt">protective</span> B. brevis 18-3 biofilm decreased the <span class="hlt">corrosion</span> rate about 20-fold compared with the non-gramicidin-producing P. polymyxa ATCC 10401 biofilm control. The mass loss for the <span class="hlt">protected</span> mild <span class="hlt">steel</span> coupons was also significantly lower than that for the unprotected ones (4-fold decrease). Scanning electron microscope images corroborated the <span class="hlt">corrosion</span> inhibition by the gramicidin-S-producing B. brevis biofilm on mild <span class="hlt">steel</span> by showing that the metal surface remained untarnished, i.e., the polishing grooves were still visible after exposure to the simultaneous attack of the sulfate-reducing bacterium and the iron-oxidizing bacterium. PMID:15278311</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:14786317','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:14786317"><span id="translatedtitle">Investigation of <span class="hlt">corrosion</span> products of <span class="hlt">steels</span> formed in cracks</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p><span class="hlt">Corrosion</span> crack of <span class="hlt">steels</span> 08Kh18N10T, 08Kh21N6M2T and 08Kh14MF has been studied. The investigations are carried out in aqueous solution containing 10% NaCl and 1 g/l oxygen at 300 deg C. The samples have been held under static strain. Determination of chemical composition of <span class="hlt">corrosion</span> products in cracks has been made using the method of X-ray spectral microanalysis. The results obtained permit to make a supposition on intermittent character of crack growth under conditions of chloride <span class="hlt">corrosion</span> crack</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:41087445','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:41087445"><span id="translatedtitle">Nanocrystallization of aluminized surface of carbon <span class="hlt">steel</span> for enhanced resistances to <span class="hlt">corrosion</span> and <span class="hlt">corrosive</span> wear</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Aluminizing is often used to improve <span class="hlt">steel</span>'s resistances to <span class="hlt">corrosion</span>, oxidation and wear. This article reports our recent attempts to further improve aluminized carbon <span class="hlt">steel</span> through surface nanocrystallization for higher resistances to <span class="hlt">corrosion</span> and <span class="hlt">corrosive</span> wear. The surface nanocrystallization was achieved using a process combining sandblasting and recovery heat treatment. The entire surface modification process includes dipping carbon <span class="hlt">steel</span> specimens into a molten Al pool to form an Al coat, subsequent diffusion treatment at elevated temperature to form an aluminized layer, sandblasting to generate dislocation network or cells, and recovery treatment to turn the dislocation cells into nano-sized grains. The grain size of the nanocrystallized aluminized surface layer was in the range of 20-100 nm. Electrochemical properties, electron work function (EWF), and <span class="hlt">corrosive</span> wear of the nanocrystalline alloyed surfaces were investigated. It was demonstrated that the nanocrystalline aluminized surface of carbon <span class="hlt">steel</span> exhibited improved resistances to <span class="hlt">corrosion</span>, wear and <span class="hlt">corrosive</span> wear. The passive film developed on the nanocrystallized aluminized surface was also evaluated in terms of its mechanical properties and adherence to the substrate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008JNuM..379...97S','SCIGOV-EN'); return false;" href="http://adsabs.harvard.edu/abs/2008JNuM..379...97S"><span id="translatedtitle">The effect of radiation on the anaerobic <span class="hlt">corrosion</span> of <span class="hlt">steel</span></span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Smart, N. R.; Rance, A. P.; Werme, L. O.</p> <p>2008-09-01</p> <p>To ensure the safe encapsulation of spent nuclear fuel elements for geological disposal, SKB of Sweden are considering using a canister, which consists of an outer copper canister and a cast iron insert. Previous work has investigated the rate of gas generation due to the anaerobic <span class="hlt">corrosion</span> of ferrous materials over a range of conditions. This paper examines the effect of radiation on the <span class="hlt">corrosion</span> of <span class="hlt">steel</span> in repository environments. Tests were carried out at two temperatures (30 °C and 50 °C), two dose rates (11 Gray h -1 and 300 Gray h -1) and in two different artificial groundwaters, for exposure periods of several months. Radiation was found to enhance the <span class="hlt">corrosion</span> rate at both dose rates but the greatest enhancement occurred at the higher dose rate. The <span class="hlt">corrosion</span> products were predominantly magnetite, with some indications of unidentified higher oxidation state <span class="hlt">corrosion</span> products being formed at the higher dose rates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:40002281','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:40002281"><span id="translatedtitle">The effect of radiation on the anaerobic <span class="hlt">corrosion</span> of <span class="hlt">steel</span></span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>To ensure the safe encapsulation of spent nuclear fuel elements for geological disposal, SKB of Sweden are considering using a canister, which consists of an outer copper canister and a cast iron insert. Previous work has investigated the rate of gas generation due to the anaerobic <span class="hlt">corrosion</span> of ferrous materials over a range of conditions. This paper examines the effect of radiation on the <span class="hlt">corrosion</span> of <span class="hlt">steel</span> in repository environments. Tests were carried out at two temperatures (30 deg. C and 50 deg. C), two dose rates (11 Gray h-1 and 300 Gray h-1) and in two different artificial groundwaters, for exposure periods of several months. Radiation was found to enhance the <span class="hlt">corrosion</span> rate at both dose rates but the greatest enhancement occurred at the higher dose rate. The <span class="hlt">corrosion</span> products were predominantly magnetite, with some indications of unidentified higher oxidation state <span class="hlt">corrosion</span> products being formed at the higher dose rates</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=20988688','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=20988688"><span id="translatedtitle"><span class="hlt">Corrosion</span> resistance of zinc-magnesium coated <span class="hlt">steel</span></span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Hosking, N.C. [Ford Motor Company Ltd., Dunton Engineering Centre, Room GB15/GM-D01, Laindon, Basildon, Essex SS15 6EE (United Kingdom) and School of Mechanical, Materials and Manufacturing Engineering, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)]. E-mail: niamh.hosking@gmail.com; Stroem, M.A. [Volvo Car Corporation, Building VCPC, Maildrop PV 1B, Volvo Jacobs vag, Goeteborg SE-405 31 (Sweden); Shipway, P.H. [School of Mechanical, Materials and Manufacturing Engineering, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom); Rudd, C.D. [School of Mechanical, Materials and Manufacturing Engineering, The University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)</p> <p>2007-09-15</p> <p>A significant body of work exists in the literature concerning the <span class="hlt">corrosion</span> behaviour of zinc-magnesium coated <span class="hlt">steel</span> (ZMG), describing its enhanced <span class="hlt">corrosion</span> resistance when compared to conventional zinc-coated <span class="hlt">steel</span>. This paper begins with a review of the literature and identifies key themes in the reported mechanisms for the attractive properties of this material. This is followed by an experimental programme where ZMG was subjected to an automotive laboratory <span class="hlt">corrosion</span> test using acidified NaCl solution. A 3-fold increase in time to red rust compared to conventional zinc coatings was measured. X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscopy were used to characterize the <span class="hlt">corrosion</span> products formed. The <span class="hlt">corrosion</span> products detected on ZMG included simonkolleite (Zn{sub 5}Cl{sub 2}(OH){sub 8} . H{sub 2}O), possibly modified by magnesium uptake, magnesium hydroxide (Mg(OH){sub 2}) and a hydroxy carbonate species. It is proposed that the oxygen reduction activity at the (zinc) cathodes is reduced by precipitation of alkali-resistant Mg(OH){sub 2}, which is gradually converted to more soluble hydroxy carbonates by uptake of atmospheric carbon dioxide. This lowers the surface pH sufficiently to allow thermodynamically for general precipitation of insoluble simonkolleite over the corroding surface thereby retarding the overall <span class="hlt">corrosion</span> reactions, leaving only small traces of magnesium <span class="hlt">corrosion</span> products behind. Such a mechanism is consistent with the experimental findings reported in the literature.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=551118','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=551118"><span id="translatedtitle"><span class="hlt">Corrosion</span> behaviour of nitrocarburized <span class="hlt">steels</span>; Korrosionsverhalten nitrocarburierter Staehle</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Pohl, M.; Al-Rubaie, K.S.; Steinmeier, F. [Bochum Univ. (Germany). Inst. fuer Werkstoffe</p> <p>1997-06-01</p> <p>Diffusion coatings have been used increasingly to modify surface properties of various machine components for several applications. In general, these coatings are used to improve the wear behaviour. Frequently, it is desirable that the <span class="hlt">corrosion</span> behaviour will be improved at the same time. In this investigation, the <span class="hlt">corrosion</span> behaviour of various diffusion coating-substrate-combinations has been studied. The coatings developed by three different nitrocarburizing processes, namely salt-bath, gas and plasma nitrocarburizing, were conducted on five various <span class="hlt">steel</span> substrates. These substrates were St 52-3, Ck 45, 42 CrMo 4, 30 CrNiMo 8 and X 20 Cr 13. The thickness of the compound layers and their porosity were measured using optical microscopy. The structure of the compound layers was characterized using an X-ray diffractometer and their surface roughness by a stylus profilometer. The <span class="hlt">corrosion</span> test was carried out using a salt-water spray test. The predominant <span class="hlt">corrosion</span> mechanisms have been evaluated using scanning electron microscopy. It was found that the employed nitrocarburizing processes have improved the <span class="hlt">corrosion</span> resistance of all tested coating-substrate-combinations comparing with that of the base materials. In general, the <span class="hlt">corrosion</span> resistance increases with an increase of the compound layer`s thickness and after an oxidation process. The best coating-substrate-combinations to improve the <span class="hlt">corrosion</span> behaviour were salt-bath nitrocarburized tempering <span class="hlt">steels</span>, whereas the thin layers of the plasma nitrocarburized specimens were the worst. (orig.) 12 refs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:47026652','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:47026652"><span id="translatedtitle"><span class="hlt">Corrosion</span> rate of carbon <span class="hlt">steel</span> in NS tank water</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Neutron shield tank (NST) is an open tank 12.5 meters in height and 12 meters dia constructed around the research reactor. It is filled with water to (i) provide shielding from the neutron radiation, (ii) to remove the heat from the Pressure suppression system during LOCA and (iii) to act as a heat sink. NST is made of IS2062 carbon <span class="hlt">steel</span> and it contains the stainless <span class="hlt">steel</span> tanks, CS support structures, forged carbon <span class="hlt">steel</span> gas cylinders, <span class="hlt">steel</span> containment and its supports and emergency cooling down system condensers made of ASTM 350 grade LF2 carbon <span class="hlt">steel</span>. All the equipments/systems located inside NST are painted with epoxy paint. NST is filled up 12 meters ie with 1200 m3 of water. The water chemistry parameters and microbiological parameters and <span class="hlt">corrosion</span> rate of carbon <span class="hlt">steel</span> materials in NST water at various water chemistry and various depths are discussed in the paper. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.etde.org/etdeweb/servlets/purl/20671850-rcfPqK/','ETDEWEB-EN'); return false;" href="https://www.etde.org/etdeweb/servlets/purl/20671850-rcfPqK/"><span id="translatedtitle">Trends in the automotive paint industry for <span class="hlt">corrosion</span> <span class="hlt">protection</span></span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Blandin, Nathalie; Brunat, William [PPG Industries France, 3 Z.A.E. Les Dix Muids, B.P. 89, F-59583 Marly (France); Neuhaus, Ralf [PPG Industries Lacke GmbH, Stackenbergstrasse 34, D-42329 Wuppertal (Germany); Sibille, Ettore [PPG Industries Italia, Via Serra11, I-15028 Quattordio (Italy)</p> <p>2004-07-01</p> <p>Since many years ED-paints are <span class="hlt">protecting</span> car bodies against <span class="hlt">corrosion</span>. Currently the automotive paint industry is faced with increasing demands of higher levels of <span class="hlt">corrosion</span> <span class="hlt">protection</span> and also requests to comply with new environmental regulations and economical pressures. Some key factors that contributed significantly towards the improvement of <span class="hlt">corrosion</span> <span class="hlt">protection</span> systems are: - New generations of lead free ED-paints; - Weldable organic thin film for <span class="hlt">corrosion</span> <span class="hlt">protection</span>, especially in box cavities and flange areas. The goal of this paper is to show how the various elements of the 'anti-<span class="hlt">corrosion</span> package' interact. (authors)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-70762015000200523&lang=en','SCIELO-EN'); return false;" href="http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-70762015000200523&lang=en"><span id="translatedtitle"><span class="hlt">Corrosion</span> Behavior and Microstructure of Borided Tool <span class="hlt">Steel</span></span></a></p> <p><a target="_blank" href="http://www.scielo.org/php/index.php?lang=en">Scientific Electronic Library Online (English)</a></p> <p>Muzaffer, Erdogan; Ibrahim, Gunes.</p> <p>2015-06-01</p> <p>Full Text Available In the present study, the <span class="hlt">corrosion</span> behaviors of borides formed on cold work tool <span class="hlt">steel</span> have been investigated in a 4% M HCl acid solution. Boriding was performed in a solid medium consisting of Ekabor-II powders at 850 and 950°C for 6 h. The boride layer was characterized by SEM, EDS, XRD and the h [...] ardness tester. XRD analysis of boride layers on the surface of the samples revealed the existence of FeB, Fe2B, CrB, Cr2B and MoB compounds. Depending on the chemical composition of substrates and boriding time, the boride layer thickness on the surface of the <span class="hlt">steel</span> ranged from 13.14 ?m and 120.82 ?m. The hardness of the boride compounds formed on the surface of the samples ranged from 1806 to 2342 HV0,05, whereas Vickers hardness values of the untreated the samples was 428 HV0,05. The <span class="hlt">corrosion</span> resistance of the borided <span class="hlt">steels</span> was higher compared with that of the unborided <span class="hlt">steels</span>. The borided <span class="hlt">steels</span> increased the <span class="hlt">corrosion</span> resistances of the <span class="hlt">steels</span> 8-17- fold.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.openaire.eu/search/publication?articleId=od______1318::2f170feccb456b442f4cdc07e0603221','DRIVER-EN'); return false;" href="https://www.openaire.eu/search/publication?articleId=od______1318::2f170feccb456b442f4cdc07e0603221"><span id="translatedtitle"><span class="hlt">Corrosion</span> behaviour of different hot rolled <span class="hlt">steels</span></span></a></p> <p><a target="_blank" href="https://www.openaire.eu/search/advanced/publications">OpenAIRE</a></p> <p>Perez, F. J.; Martinez, L.; Hierro, M. P.; Gomez, C.; Portela, A. L.; G.N. Pucci; Duday, D.; Lecomte-Beckers, Jacqueline; Greday, Y.</p> <p>2006-01-01</p> <p>The oxidation-<span class="hlt">corrosion</span> behaviour of hot rolled alloys was examined by electrochemical impedance spectroscopy. The <span class="hlt">corrosion</span> behaviour of the non-oxidised alloys was first determined in order to have a reference behaviour. Then, each alloy was oxidised for 1 and 3 days at 650 degrees C in air and its <span class="hlt">corrosion</span> behaviour was also determined. For all the alloys, Fe2O3 was formed at the scale-gas interface. However, the Fe2O3 crystallographic structures varied as a function of the alloy composit...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:36105084','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:36105084"><span id="translatedtitle"><span class="hlt">Corrosion</span> behaviour of carbon <span class="hlt">steel</span> in the Tournemire clay</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Carbon <span class="hlt">steels</span> are possible materials for the fabrication of nuclear waste containers for long term geological disposal in argillaceous environments. Experimental studies of the <span class="hlt">corrosion</span> behaviour of such materials has been conducted in various conditions. Concerning the numerous laboratory experiments, these conditions (water and clay mixture or compacted clay) mainly concern the bentonite clay that would be used for the engineered barrier. On the opposite, only few in-situ experiments has been conducted directly in the local clay of the repository site (such as Boom clay, etc.). In order to better estimate the <span class="hlt">corrosion</span> behaviour of carbon <span class="hlt">steels</span> in natural clay site conditions, an experimental study has been conducted jointly by EDF and IRSN in the argillaceous French site of Tournemire. In this study, A42 carbon <span class="hlt">steel</span> specimens have been exposed in 3 different zones of the Tournemire clay formation. The first type of environmental conditions concerns a zone where the clay has not been affected by the excavation (EDZ) of the main tunnel neither by the main fracture zone of the clay formation. The second and third ones are located in the EDZ of the tunnel. In the second zone, an additional aerated water flows from the tunnel, whereas it does not in the third place. Some carbon <span class="hlt">steel</span> specimens have been extracted after several years of exposure to these conditions. The average <span class="hlt">corrosion</span> rate has been measured by the weight loss technique and the pitting <span class="hlt">corrosion</span> depth has been evaluated under an optical microscope. <span class="hlt">Corrosion</span> products have also been characterised by scanning electron microscopy and X-ray diffraction technique. Results are then discussed regarding the surrounding environmental conditions. Calculations of the oxygen transport from the tunnel through the clay and of the clay re-saturation can explain, in a first approach, the <span class="hlt">corrosion</span> behaviour of the carbon <span class="hlt">steel</span> in the different tested zones. (authors)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=20856740','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=20856740"><span id="translatedtitle">Mangrove tannins and their flavanoid monomers as alternative <span class="hlt">steel</span> <span class="hlt">corrosion</span> inhibitors in acidic medium</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Rahim, Afidah A. [School of Chemical Sciences, University Sains Malaysia, 11800 Penang (Malaysia)]. E-mail: afidah@usm.my; Rocca, E. [Laboratoire de Chimie du Solide Mineral, Universite Henri Poincare, Nancy I BP 239, 54506 Vandoeuvre Les Nancy (France); Steinmetz, J. [Laboratoire de Chimie du Solide Mineral, Universite Henri Poincare, Nancy I BP 239, 54506 Vandoeuvre Les Nancy (France); Kassim, M.J. [School of Chemical Sciences, University Sains Malaysia, 11800 Penang (Malaysia); Adnan, R. [School of Chemical Sciences, University Sains Malaysia, 11800 Penang (Malaysia); Sani Ibrahim, M. [School of Chemical Sciences, University Sains Malaysia, 11800 Penang (Malaysia)</p> <p>2007-02-15</p> <p>The inhibitive behaviour on <span class="hlt">steel</span> of flavanoid monomers that constitute mangrove tannins namely catechin, epicatechin, epigallocatechin and epicatechingallate was investigated in an aerated HCl solution via electrochemical methods. The monomers were found to be mainly cathodic inhibitors and the inhibition efficiency was dependent on concentration. To explain the adsorptive behaviour of the molecules on the <span class="hlt">steel</span> surface, a semiempirical approach involving quantum chemical calculations using HyperChem 6.0 was undertaken. The HOMO electronic density of the molecule was used to explain the inhibiting mechanism. The most probable adsorption centers were found in the vicinity of the phenolic groups. In a second part, the use of mangrove tannin, extracted from the mangrove barks as <span class="hlt">steel</span> <span class="hlt">corrosion</span> inhibitors in acidic media was investigated and its inhibitive efficiency was compared with that of commercial mimosa, quebracho and chestnut tannins. The inhibitive performance of mangrove tannins was comparable to the other tannins investigated, indicating their potential in <span class="hlt">corrosion</span> <span class="hlt">protection</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-97072015000100004&lang=en','SCIELO-EN'); return false;" href="http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-97072015000100004&lang=en"><span id="translatedtitle">STUDY OF <span class="hlt">CORROSION</span> INHIBITION PROPERTIES OF NOVEL SEMICARBAZONES ON MILD <span class="hlt">STEEL</span> IN ACIDIC SOLUTIONS</span></a></p> <p><a target="_blank" href="http://www.scielo.org/php/index.php?lang=en">Scientific Electronic Library Online (English)</a></p> <p>RATHIKA, GOVINDASAMY; SWETHA, AYAPPAN.</p> <p>2015-03-01</p> <p>Full Text Available The inhibition efficiency of <span class="hlt">corrosion</span> on mild <span class="hlt">steel</span> using acids by three different novel Semicarbazones as inhibitors have been studied using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy methods. The inhibition efficiency, <span class="hlt">corrosion</span> rate, the nature of anchor [...] ing sites and the adsorption characteristics have been determined from the results. It was found that the newly synthesized compounds behaved as mixed type inhibitors with high inhibition efficiency. The inhibition efficiency increases with increasing the inhibitors concentration but decreases with increasing the temperature. Addition of halide ion enhances the inhibition efficiency. The adsorption of the inhibitors on the mild <span class="hlt">steel</span> surface obey Langmuir adsorption isotherm. Scanning Electron Spectroscopy is used to examine the surface morphology of mild <span class="hlt">steel</span> samples both in the presence and absence of inhibitors at optimum conditions. Scanning Electron Microscope reveals the formation of a smooth, dense <span class="hlt">protective</span> layer in the presence of inhibitor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24061751','SCIGOV-EN'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24061751"><span id="translatedtitle">The Inhibition of Mild <span class="hlt">Steel</span> <span class="hlt">Corrosion</span> in 1 N HCl by Imidazole Derivatives.</span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Patel, Niketan S; Jauhari, Smita; Mehta, Girishkumar N</p> <p>2010-06-01</p> <p>The inhibition effect of imidazole derivatives 4-methyl-2-propyl-1H-benzimidazole-6-carboxylic acid (MPBI) and 1,4'-Dimethyl-2'-propyl-1H,3'H-2,5'-dibenzimidazole (DPBI) against mild <span class="hlt">steel</span> <span class="hlt">corrosion</span> in 1 N HCl solutions were evaluated using conventional weight loss, potentiodynamic polarization, linear polarization and electrochemical impedance spectroscopy. The weight loss results showed that both are excellent <span class="hlt">corrosion</span> inhibitors, electrochemical polarizations data revealed the mixed mode of inhibition and the results of electrochemical impedance spectroscopy have shown that the change in the impedance parameters, charge transfer resistance and double layer capacitance, with the change in concentration of the inhibitor is due to the adsorption of the molecule leading to the formation of a <span class="hlt">protective</span> layer on the surface of mild <span class="hlt">steel</span>. The inhibition action of these compounds was, assumed to occur via adsorption on the <span class="hlt">steel</span> surface through the active centres contained of the molecule. PMID:24061751</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:37115505','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:37115505"><span id="translatedtitle">Bio-<span class="hlt">corrosion</span> in synthetic and natural sea water of modified stainless <span class="hlt">steels</span> by poison elements</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>In seawater, bacteria can modify the behaviour of stainless <span class="hlt">steels</span> towards <span class="hlt">corrosion</span>. It can be then considered to control this type of degradation by a better adjustment of the chemical composition of the <span class="hlt">steels</span> used. In this work, has been studied the influence of the addition of 'poisons' elements for bacteria on the bio-<span class="hlt">corrosion</span> resistance of an austenitic 316L <span class="hlt">steel</span>. The added elements were copper, tin and arsenic. After a bibliographic study and a description of the metallographic, electrochemical and surface analyses methods used, the results obtained in the considered media are given: synthetical seawater, natural, or sterilized and then inoculated. The specific role of each addition elements has then been revealed as well as the alteration of the <span class="hlt">protecting</span> films and of the induced bio-film, and the behaviour differences in aerobic and anaerobic conditions. (O.M.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:38028898','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:38028898"><span id="translatedtitle">Mangrove tannins and their flavanoid monomers as alternative <span class="hlt">steel</span> <span class="hlt">corrosion</span> inhibitors in acidic medium</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>The inhibitive behaviour on <span class="hlt">steel</span> of flavanoid monomers that constitute mangrove tannins namely catechin, epicatechin, epigallocatechin and epicatechingallate was investigated in an aerated HCl solution via electrochemical methods. The monomers were found to be mainly cathodic inhibitors and the inhibition efficiency was dependent on concentration. To explain the adsorptive behaviour of the molecules on the <span class="hlt">steel</span> surface, a semiempirical approach involving quantum chemical calculations using HyperChem 6.0 was undertaken. The HOMO electronic density of the molecule was used to explain the inhibiting mechanism. The most probable adsorption centers were found in the vicinity of the phenolic groups. In a second part, the use of mangrove tannin, extracted from the mangrove barks as <span class="hlt">steel</span> <span class="hlt">corrosion</span> inhibitors in acidic media was investigated and its inhibitive efficiency was compared with that of commercial mimosa, quebracho and chestnut tannins. The inhibitive performance of mangrove tannins was comparable to the other tannins investigated, indicating their potential in <span class="hlt">corrosion</span> <span class="hlt">protection</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:26011181','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:26011181"><span id="translatedtitle">Case histories of microbiologically influenced <span class="hlt">corrosion</span> of austenitic stainless <span class="hlt">steel</span> weldments</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Microbiologically influenced <span class="hlt">corrosion</span> (MIC) is initiated or accelerated by microorganisms and is currently recognized as a serious problem affecting the construction and operation of many industrial facilities, including nuclear power plants. The purpose of this paper is to review how biofouling and MIC can occur and discuss current mechanistic theories. A case history of MIC attack in power plants is examined with emphasis on the role of welding and heat treatment variables using laboratory electrochemical analyses. Although MIC can occur on a variety of alloys, pitting <span class="hlt">corrosion</span> failures of austenitic stainless <span class="hlt">steels</span> are often associated with weldments. MIC occurs as the result of a consortium of microorganisms colonizing on the metal surface and their variety (fungi, bacteria, algae, mold, and slimes) enables them to form support systems for cross feeding to enhance survival. The metabolic processes influence <span class="hlt">corrosion</span> behaviour of materials by destroying <span class="hlt">protective</span> coatings, producing a localized acid environment, creating <span class="hlt">corrosive</span> deposits, or altering anodic and cathodic reactions. On stainless <span class="hlt">steels</span>, biofilms destroy the passive oxide film on the surface of the <span class="hlt">steels</span> and subject them to localized forms of <span class="hlt">corrosion</span>. Many of the MIC failures in industry result in pitting to austenitic stainless <span class="hlt">steel</span> weldments. Pitting primarily occurs in the weld metal, heat affected zones, and adjacent to the weld in the base metal. Depending on the conditions of the concentration cell created by the biofilm, either phase of the two-phase duplex stainless <span class="hlt">steel</span>, austenite or delta ferrite, may be selectively attacked. Theories have been proposed about the mechanism of MIC on austenitic stainless <span class="hlt">steel</span> and and a general understanding is that some function associated with the biofilm formation directly affects the electrochemical process</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:45105586','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:45105586"><span id="translatedtitle">Contribution of acoustic emission to monitor the effect of phosphate based inhibitor on the <span class="hlt">corrosion</span> behavior of <span class="hlt">steel</span> reinforcement</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>One of the most important causes of reinforced concrete structures deterioration is the <span class="hlt">corrosion</span> of the reinforcement <span class="hlt">steel</span>. This <span class="hlt">corrosion</span> depends on the presence of aggressive agents such as chlorides in the surrounding medium. Numerous <span class="hlt">protection</span> techniques have been employed to mitigate this <span class="hlt">corrosion</span>. Among them, the use of <span class="hlt">corrosion</span> inhibitors has been considered as one of the most effective solutions. In the present work, the influence of phosphate based inhibitor on the <span class="hlt">corrosion</span> of reinforcing <span class="hlt">steels</span> embedded in mortar, and immersed in sodium chloride solution, was investigated by acoustic emission technique. The monitoring of specimens shows that the phosphate based inhibitor addition in the mortar increase the threshold of chloride concentrations, causing the breakdown of <span class="hlt">steel</span> passivation layer. Thus, the acoustic signatures of concrete fracture and of structure degradation during the <span class="hlt">corrosion</span> of these specimens have been highlighted. Similarly, the mechanism of phosphate action in terms of preventing <span class="hlt">steel</span> from <span class="hlt">corrosion</span> in mortar specimens was analysed by characterization methods (SEM, XRD) of the <span class="hlt">steel</span>-mortar interface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=22284178','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=22284178"><span id="translatedtitle">Contribution of acoustic emission to monitor the effect of phosphate based inhibitor on the <span class="hlt">corrosion</span> behavior of <span class="hlt">steel</span> reinforcement</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Nahali, Haifa [Laboratoire MATEIS CNRS UMR5511 (Equipe CorrIS), INSA-Lyon, Villeurbanne (France); Univ. de Tunis El Manar, Belvedere (Tunisia). Unite de Recherche ' ' Mecanique-Energetique' ' ; Dhouibi, Leila [Univ. de Tunis El Manar, Belvedere (Tunisia). Unite de Recherche ' ' Mecanique-Energetique' ' ; Idrissi, Hassane [Laboratoire MATEIS CNRS UMR5511 (Equipe CorrIS), INSA-Lyon, Villeurbanne (France)</p> <p>2014-11-01</p> <p>One of the most important causes of reinforced concrete structures deterioration is the <span class="hlt">corrosion</span> of the reinforcement <span class="hlt">steel</span>. This <span class="hlt">corrosion</span> depends on the presence of aggressive agents such as chlorides in the surrounding medium. Numerous <span class="hlt">protection</span> techniques have been employed to mitigate this <span class="hlt">corrosion</span>. Among them, the use of <span class="hlt">corrosion</span> inhibitors has been considered as one of the most effective solutions. In the present work, the influence of phosphate based inhibitor on the <span class="hlt">corrosion</span> of reinforcing <span class="hlt">steels</span> embedded in mortar, and immersed in sodium chloride solution, was investigated by acoustic emission technique. The monitoring of specimens shows that the phosphate based inhibitor addition in the mortar increase the threshold of chloride concentrations, causing the breakdown of <span class="hlt">steel</span> passivation layer. Thus, the acoustic signatures of concrete fracture and of structure degradation during the <span class="hlt">corrosion</span> of these specimens have been highlighted. Similarly, the mechanism of phosphate action in terms of preventing <span class="hlt">steel</span> from <span class="hlt">corrosion</span> in mortar specimens was analysed by characterization methods (SEM, XRD) of the <span class="hlt">steel</span>-mortar interface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:38049256','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:38049256"><span id="translatedtitle">Evaluation of the <span class="hlt">corrosion</span> resistance of the galvanized SS400 <span class="hlt">steel</span> in NaCl solutions</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>A typical CANDU plant generates about 5,000 spent fuel bundles annually, which are stored in a spent fuel pool. Because the storage capacity of a spent pool is 10 years of spent fuel bundles, the Silo type storage modules are used to store the extra fuel bundles. In a multi-unit site like Wolsong, the extra space needed for the Silo type storage modules are ever increasing with the operating years. Therefore a more space effective storage system is necessary to accommodate all the extra spent fuels from the four CANDU units at site. A new dry storage system, MACSTOR/KN-400 (M/KN- 400) that is based upon MACSTOR design concept was developed. M/KN-400 will be built at the seaside in Wolsong site and galvanized carbon <span class="hlt">steel</span> will be used for storage cylinder material to <span class="hlt">protect</span> from the <span class="hlt">corrosion</span>. Generally, galvanized carbon <span class="hlt">steels</span>, in which the Zn layer on the surface acts as a sacrificial anode, are known to have good <span class="hlt">corrosion</span> resistance in the atmospheric or aqueous conditions. However, in the brine condition containing chloride ions or steam environment, the Zn layer can be damaged. Therefore, considering the seaside atmosphere in which the storage system are located, the integrity of the storage cylinder is likely to be affected by the <span class="hlt">corrosion</span> caused by the salt included in the atmosphere. In this study, electrochemical <span class="hlt">corrosion</span> tests were performed on the galvanized carbon <span class="hlt">steels</span> to estimate the <span class="hlt">corrosion</span> resistance of the storage cylinder</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JTST...24..629P','SCIGOV-EN'); return false;" href="http://adsabs.harvard.edu/abs/2015JTST...24..629P"><span id="translatedtitle">Mitigating Localized <span class="hlt">Corrosion</span> Using Thermally Sprayed Aluminum (TSA) Coatings on Welded 25% Cr Superduplex Stainless <span class="hlt">Steel</span></span></a></p> <p><a target="_blank" href="http://www.science.gov/">Science.gov (United States)</a></p> <p>Paul, S.; Lu, Q.; Harvey, M. D. F.</p> <p>2015-04-01</p> <p>Thermally sprayed aluminum (TSA) coating has been increasingly used for the <span class="hlt">protection</span> of carbon <span class="hlt">steel</span> offshore structures, topside equipment, and flowlines/pipelines exposed to both marine atmospheres and seawater immersion conditions. In this paper, the effectiveness of TSA coatings in preventing localized <span class="hlt">corrosion</span>, such as pitting and crevice <span class="hlt">corrosion</span> of 25% Cr superduplex stainless <span class="hlt">steel</span> (SDSS) in subsea applications, has been investigated. Welded 25% Cr SDSS (coated and uncoated) with and without defects, and surfaces coated with epoxy paint were also examined. Pitting and crevice <span class="hlt">corrosion</span> tests, on welded 25% Cr SDSS specimens with and without TSA/epoxy coatings, were conducted in recirculated, aerated, and synthetic seawater at 90 °C for 90 days. The tests were carried out at both the free <span class="hlt">corrosion</span> potentials and an applied cathodic potential of -1100 mV saturated calomel electrode. The acidity (pH) of the test solution was monitored daily and adjusted to between pH 7.5 and 8.1, using dilute HCl solution or dilute NaOH, depending on the pH of the solution measured during the test. The test results demonstrated that TSA prevented pitting and crevice <span class="hlt">corrosion</span> of 25% Cr SDSS in artificial seawater at 90 °C, even when 10-mm-diameter coating defect exposing the underlying <span class="hlt">steel</span> was present.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=20883785','ETDEWEB-EN'); return false;" href="http://www.etde.org/etdeweb/details.jsp?query_id=1&page=0&osti_id=20883785"><span id="translatedtitle">Evaluation of the <span class="hlt">corrosion</span> resistance of the galvanized SS400 <span class="hlt">steel</span> in NaCl solutions</span></a></p> <p><a target="_blank" href="https://www.etde.org/etdeweb/fieldedsearch.jsp">Energy Technology Data Exchange (ETDEWEB)</a></p> <p>Hong, Seung Mo; Jang, Chang Heui; Kim, In Sup [KAIST, Taejon (Korea, Republic of); Lee, Kyung Ho; Choi, Byung Il [Korea Hydro and Nuclear Power Co., Taejon (Korea, Republic of)</p> <p>2006-07-01</p> <p>A typical CANDU plant generates about 5,000 spent fuel bundles annually, which are stored in a spent fuel pool. Because the storage capacity of a spent pool is 10 years of spent fuel bundles, the Silo type storage modules are used to store the extra fuel bundles. In a multi-unit site like Wolsong, the extra space needed for the Silo type storage modules are ever increasing with the operating years. Therefore a more space effective storage system is necessary to accommodate all the extra spent fuels from the four CANDU units at site. A new dry storage system, MACSTOR/KN-400 (M/KN- 400) that is based upon MACSTOR design concept was developed. M/KN-400 will be built at the seaside in Wolsong site and galvanized carbon <span class="hlt">steel</span> will be used for storage cylinder material to <span class="hlt">protect</span> from the <span class="hlt">corrosion</span>. Generally, galvanized carbon <span class="hlt">steels</span>, in which the Zn layer on the surface acts as a sacrificial anode, are known to have good <span class="hlt">corrosion</span> resistance in the atmospheric or aqueous conditions. However, in the brine condition containing chloride ions or steam environment, the Zn layer can be damaged. Therefore, considering the seaside atmosphere in which the storage system are located, the integrity of the storage cylinder is likely to be affected by the <span class="hlt">corrosion</span> caused by the salt included in the atmosphere. In this study, electrochemical <span class="hlt">corrosion</span> tests were performed on the galvanized carbon <span class="hlt">steels</span> to estimate the <span class="hlt">corrosion</span> resistance of the storage cylinder.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:23046938','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:23046938"><span id="translatedtitle">Carbon <span class="hlt">steel</span> <span class="hlt">protection</span> in G.S. (Girlder sulfide) plants. CITROSOLV process influence. Pt. 6</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>In order to <span class="hlt">protect</span> carbon <span class="hlt">steel</span> towers and piping of Girlder sulfide (G.S.) experimental heavy water plants against <span class="hlt">corrosion</span> produced by the action of aqueous solutions of hydrogen sulfides, a method, previously published, was developed. Carbon <span class="hlt">steel</span>, exposed to saturated aqueous solutions of hydrogen sulfide, forms iron sulfide scales. In oxygen free solutions evolution of <span class="hlt">corrosion</span> follows the sequence: mackinawite ? cubic ferrous sulfide ? troilite ? pyrrotite ? pyrite. Scales formed by pyrrotite-pyrite or pyrite are the most <span class="hlt">protective</span> layers (these are obtained at 130 deg C, 2 MPa, for periods of 14 days). CITROSOLV Process (Pfizer) is used to descaling and passivating stainless <span class="hlt">steel</span> plant's components. This process must be used in mixed (carbon <span class="hlt">steel</span> - stainless <span class="hlt">steel</span>) circuits and may cause the formation of magnetite scales over the carbon <span class="hlt">steel</span>. The influence of magnetite in the pyrrotite-pyrite scales formation is studied in this work. (Author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:40069837','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:40069837"><span id="translatedtitle"><span class="hlt">Corrosion</span> rate of ferritic ODS stainless <span class="hlt">steels</span> in a supercritical water environment</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Full text of publication follows: The <span class="hlt">corrosion</span> behavior of several ODS (Oxide Dispersion Strengthened) <span class="hlt">steels</span> (Fe-xCryAl-zW-Y2O3) were studied. A <span class="hlt">corrosion</span> experiment was performed up to 1000 hrs in 510 deg. C and 25 MPa pure water environments. The dissolved oxygen content was controlled by exposing the test solution to laboratory air at the start of the test. The weight gain of each sample was used to estimate the amount of <span class="hlt">corrosion</span> assuming dissolution rates to be small. Low angle X-ray diffraction method was applied for characterizing the surface oxide resulting from <span class="hlt">corrosion</span> reactions. further, the cross section area was observed by FESEM-EPMA to reveal the morphology and composition of the oxide. The weight gain increased with time and after a certain time, it reached a steady state. Using the weight gain data, we estimated the <span class="hlt">corrosion</span> rate defined as the ratio of weight gain and the test interval. The <span class="hlt">corrosion</span> rate decreased with time, which reflected that the oxide film became <span class="hlt">protective</span> for all the ODS <span class="hlt">steels</span>. From XRD and FESEM-EPMA studies, the oxide layers were examined to be Cr rich spinel at the early test period and to become Cr oxide (Cr2O3) after a certain time due to phase transformation. The Cr oxide formation inhibited further <span class="hlt">corrosion</span>, reaching the steady state. No exclusive aluminum oxide layer was formed in the test condition. Nonetheless, the summation of Cr and Al content represented the <span class="hlt">corrosion</span> resistance of ODS <span class="hlt">steels</span>. (authors)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://inis.iaea.org/search/search.aspx?orig_q=RN:43049678','IAEA-INISDB-EN'); return false;" href="http://inis.iaea.org/search/search.aspx?orig_q=RN:43049678"><span id="translatedtitle">Sodium phthalamates as <span class="hlt">corrosion</span> inhibitors for carbon <span class="hlt">steel</span> in aqueous hydrochloric acid solution</span></a></p> <p><a target="_blank" href="http://inis.iaea.org/search/">International Nuclear Information System (INIS) </a></p> <p></p> <p></p> <p>Highlights: ? N-Alkyl-sodium phthalamates as <span class="hlt">corrosion</span> inhibitors for industry in acidic medium. ? Compounds behaved as mixed type inhibitors and followed Langmuir adsorption isotherm. ? Efficiencies were proportional to aliphatic chain length and inhibitor concentration. ? Iron complexes and chelates with phthalamates contributed to carbon <span class="hlt">steel</span> <span class="hlt">protection</span>. - Abstract: Three compounds of N-alkyl-sodium phthalamates were synthesized and tested as <span class="hlt">corrosion</span> inhibitors for carbon <span class="hlt">steel</span> in 0.5 M aqueous hydrochloric acid. Tests showed that inhibitor efficiencies were related to aliphatic chain length and dependent on concentration. N-1-n-tetradecyl-sodium phthalamate displayed moderate efficiency against uniform <span class="hlt">corrosion</span>, 42-86% at 25 deg. C and 25-60% at 40 oC. Tests indicated that compounds behave as mixed type inhibitors where molecular adsorption on <span class="hlt">steel</span> followed Langmuir isotherm, whereas thermodynamic suggested that a physisorption process occurred. XPS analysis confirmed film formation on surface, where Fe+2 complexes and Fe+2 chelates with phthalamates prevented <span class="hlt">steel</span> from further <span class="hlt">corrosion</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <center> <div class="footer-extlink text-muted"><small>Some links on this page may take you to non-federal websites. 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