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1
Kumaraguru, Murali. "Electrochemical studies related to automotive corrosion." Thesis, University of Manchester, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488117.
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2
Peggs, Lee James. "Electrochemical studies of iron corrosion inhibitors." Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285364.
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3
Lowe, Alexander M. "Estimation of electrochemical noise impedance and corrosion rates from electrochemical noise measurements." Thesis, Curtin University, 2002. http://hdl.handle.net/20.500.11937/209.
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Electrochemical noise refers to the spontaneous fluctuations in potential and current that can be observed on a corroding metal. The use of electrochemical noise for obtaining information on the corrosion process generates much interest in research fields. One important application is the measurement of corrosion rate. This can be achieved using the electrochemical noise of a pair of electrically coupled corroding metals to obtain an estimate of electrochemical impedance - an abstract quantity that reflects various aspects of the corrosion process.There are a number of problems associated with estimation of impedance information from the electrochemical noise data, particularly regarding data pre-treatment, accuracy and precision. In addition, the present methods are incomplete: current literature does not offer information regarding the phase of the impedance; and assumptions regarding symmetry of an electrode pair cannot be tested without additional measurements.The thesis addresses the above mentioned problems. Specifically,analysis of the impedance estimation process is given to determine how precision can be affected by various factors;a novel signal processing technique is described that is shown to yield a local optimum precision;the application of the proposed signal processing to time varying systems is demonstrated by use of a time varying, frequency dependent impedance estimate;a technique for recovering phase information, given certain conditions, is suggested so that Nyquist impedance diagrams can be constructed; anda technique for testing the symmetry of a coupled pair of corroding metals is described.An integral part of electrochemical noise analysis is the software used for numerical computation. The Matlab package from MathWorks inc. provides an extensible platform for electrochemical noise analysis. Matlab code is provided in Appendix A to implement much of the theory discussed in the thesis.Impedance analysis and many other electrochemical corrosion monitoring techniques are primarily used for uniform corrosion, where the corrosion patterns occur uniformly over the exposed surface. In order to map localised corrosion, where the corrosion is typically concentrated within a small area, a wire beam electrode can be used. A wire beam electrode is a surface that is divided into a matrix of mini-electrodes so that the corrosion rate at different points can be monitored. However, manual connection of each mini-electrode to the measurement device can prove cumbersome. The final chapter of this thesis describes the design and testing of specialised multiplexing hardware to automate the process.In general, the thesis shows that by careful conditioning of the electrochemical noise prior to analysis, many of the problems with the technique of impedance estimation from the electrochemical noise data can be overcome. It is shown that the electrochemical noise impedance estimation can be extended to encompass a time varying, frequency dependent quantity for studying dynamic systems; that phase information can be recovered from electrochemical noise for the purpose of constructing Nyquist impedance diagrams; and that asymmetric electrodes can be detected without requiring additional measurements.
4
Lowe, Alexander M. "Estimation of electrochemical noise impedance and corrosion rates from electrochemical noise measurements." Curtin University of Technology, School of Electrical and Computer Engineering, 2002. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=12723.
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Electrochemical noise refers to the spontaneous fluctuations in potential and current that can be observed on a corroding metal. The use of electrochemical noise for obtaining information on the corrosion process generates much interest in research fields. One important application is the measurement of corrosion rate. This can be achieved using the electrochemical noise of a pair of electrically coupled corroding metals to obtain an estimate of electrochemical impedance - an abstract quantity that reflects various aspects of the corrosion process.There are a number of problems associated with estimation of impedance information from the electrochemical noise data, particularly regarding data pre-treatment, accuracy and precision. In addition, the present methods are incomplete: current literature does not offer information regarding the phase of the impedance; and assumptions regarding symmetry of an electrode pair cannot be tested without additional measurements.The thesis addresses the above mentioned problems. Specifically,analysis of the impedance estimation process is given to determine how precision can be affected by various factors;a novel signal processing technique is described that is shown to yield a local optimum precision;the application of the proposed signal processing to time varying systems is demonstrated by use of a time varying, frequency dependent impedance estimate;a technique for recovering phase information, given certain conditions, is suggested so that Nyquist impedance diagrams can be constructed; anda technique for testing the symmetry of a coupled pair of corroding metals is described.An integral part of electrochemical noise analysis is the software used for numerical computation. The Matlab package from MathWorks inc. provides an extensible platform for electrochemical noise analysis. Matlab code is provided in Appendix A to implement ++much of the theory discussed in the thesis.Impedance analysis and many other electrochemical corrosion monitoring techniques are primarily used for uniform corrosion, where the corrosion patterns occur uniformly over the exposed surface. In order to map localised corrosion, where the corrosion is typically concentrated within a small area, a wire beam electrode can be used. A wire beam electrode is a surface that is divided into a matrix of mini-electrodes so that the corrosion rate at different points can be monitored. However, manual connection of each mini-electrode to the measurement device can prove cumbersome. The final chapter of this thesis describes the design and testing of specialised multiplexing hardware to automate the process.In general, the thesis shows that by careful conditioning of the electrochemical noise prior to analysis, many of the problems with the technique of impedance estimation from the electrochemical noise data can be overcome. It is shown that the electrochemical noise impedance estimation can be extended to encompass a time varying, frequency dependent quantity for studying dynamic systems; that phase information can be recovered from electrochemical noise for the purpose of constructing Nyquist impedance diagrams; and that asymmetric electrodes can be detected without requiring additional measurements.
5
Tan, Yong-jun. "Electrochemical studies on carbon dioxide corrosion and its inhibition." Thesis, Curtin University, 1996. http://hdl.handle.net/20.500.11937/359.
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This thesis mainly concerns the application of electrochemical impedance spectroscopy (EIS) and electrochemical noise analysis (ENA) to the study of CO(subscript)2 corrosion of mild steel and its inhibition. The primary focus is on the use of EIS and ENA to monitor inhibitor film performance and to evaluate inhibitor film persistency.EIS was shown to be a suitable technique to study CO(subscript)2 corrosion product scale, and inhibitor films. The formation and deterioration of protective scales and inhibitor films is found to be accompanied by characteristic spectral changes and a rapid change in electrode impedance. EIS data were used to calculate corrosion related parameters such as the resistances and capacitances of inhibitor layers, and the charge transfer resistance and double layer capacitance. These parameters were used to analyse inhibitor mechanisms, determine corrosion rates and the persistence of inhibitor films.ENA is also a suitable technique to monitor the formation and deterioration of inhibitor films. It has the advantage of being able to monitor rapid processes which occur within one second. Several technical and theoretical developments were made in this thesis including the development of a new method of instantaneous corrosion rate measurement to study fast corrosion processes (the continuous noise resistance calculation method). Experimentally, the noise resistance was confirmed to be similar to linear polarisation resistance in the systems studies. The theoretical background and the advantages and disadvantages of the ENA technique are also discussed.Corrosion product scales formed under different conditions were investigated using EIS and surface analysis techniques. Temperature, pressure and exposure time were confirmed to be the important factors influencing the degree of protection given by the scale. The morphology of corrosion scales showed an obvious correlation to their protective ability. Electron microscopy revealed two types of crystal structures on corroded steel coupons. The smaller crystals associated with one of these structures was found to contribute most to corrosion protection.Several typical CO(subscript)2 corrosion inhibitors, including an imidazoline and a quaternised amine, were studied by EIS. A multi-layer model was employed to explain the EIS characteristics and self-repairing ability of imidazoline films. A quaternised amine film is most probably a physically or electrostatically adsorbed molecular layer which forms rapidly and desorbs easily.The deterioration of films, formed by commercial batch treatment inhibitors, was found to occur in three stages which were indicated or characterised by Bode phase-angle plots. A method to determine inhibitor film persistency was developed. This method is based on determining the three stages of inhibitor film deterioration, and the continuous measurement of corrosion rate, which is accessible at the second and third stages of film deterioration.
6
Dominguez, Olivo Juan M. "Electrochemical Model of Carbon Dioxide Corrosion in the Presence of Organic Corrosion Inhibitors." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1577092234789695.
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Jenkins, Andrew Tobias Aveling. "Electrochemical studies of coating degradation." Thesis, University of Newcastle Upon Tyne, 1995. http://hdl.handle.net/10443/967.
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The polymer coatings considered in this thesis work principally by creating a barrier, in order to prevent a corroding medium such as water and / or oxygen from contacting the surface of the underlying metal. Such coatings are subject to attack from the environment in which they are placed. This attack can lead to failure of the coating and corrosion of the underlying metal. In this thesis, three principle means of coating degradation, leading to subsequent corrosion of the substrate have been considered: Mechanical damage of the coating, the effect of ultra-violet light weathering and filiform corrosion. Electrochemical measurements have been made in order to attempt to quantify both the degree of coating breakdown and the extent of corrosion of the substrate. The principle method for measuring coating breakdown and substrate corrosion utilised in the work for this thesis was Electrochemical Impedance Spectroscopy (EIS). EIS, in principle, allows both changes in coating porosity resulting from coating breakdown, and the extent of corrosion of the substrate to be measured. The extent of delamination under polymer coatings on defects of different sizes and on different substrates has been measured. The effect of ultra-violet light weathering of polymer coatings was measured using EIS and correlated with measurements of light reflection of the coating. Filiform corrosion was induced on two different substrates, coated with various coatings. The effect of substrate and coating on filiform corrosion growth rate and mechanism has been considered.
8
Wang, Hansheng. "Electrochemical investigation of "green" film-forming corrosion inhibitors :." Thesis, KTH, Skolan för kemivetenskap (CHE), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-40888.
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In this work, a comparative electrochemical study has been performed to evaluate corrosion inhibition property of several film-forming corrosion inhibitors provide by Akzo Nobel on carbon steel in a chloride solution. For carbon steel exposed to 1 M NaCl solution with and without added inhibitor, electrochemical measurements including electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR) at different exposure time intervals, and potentiodynamic polarization at the termination of the exposure, have been performed to investigate the film forming process and to evaluate corrosion inhibition efficiency of the inhibitors, as well as its evolution with time. The corrosion resistance data obtained from the EIS and LPR measurements are in good agreement. The results indicate different inhibition properties of the inhibitors tested. The inhibition effect of SSF CI-1 is negligible in the first hour of exposure, but it increases steadily with time for 1 day, and then remains the same level during the exposure up to one week. SSF CI-2 exhibits a good inhibition effect in the first hour, but the effect decreases with time to a low level after 8 hours, and then increases again with prolonged exposure. SSF CI-4 shows a low inhibition effect during the first day, and then increases to a maximum level after three days’ exposure. For SSF CI-5 and SSF CI-6, the inhibition effect within 8 hours is relative low but higher than that of SSF CI-4, and the effect increases with time during prolonged exposure. The SSF CI-5 seems to be better than SSF CI-6 because of a more stable inhibition effect. The EIS results indicate that most of the inhibitors form a resistive surface film on carbon steel, which becomes more resistive and protective after several days’ of exposure. However, in the initial stage of exposure, the SSF CI-6 does not show an effect of formation of a resistive film on the surface. The potentiodynamic polarization measurements suggest that, SSF CI-1 and SSF CI-2 are anodic type inhibitor, SSF CI-4 is cathodic type inhibitor, and SSF CI-5 and SSF CI-6 are mix type inhibitor. Moreover, the inhibitors tested show a similar corrosion inhibition effect as mussel adhesive protein (MAP) at the low dosage level.
9
Treeman, Nicole M. "Electrochemical study of corrosion phenomena in zirconium alloys." Thesis, Cambridge, Massachusetts, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/10945/37785.
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CIVINSShadow corrosion of zirconium alloy fuel cladding in BWR environments, the phenomenon in which accelerated corrosion is experienced when the cladding surface is in close proximity to other metals, has become a potential life-limiting issue for BWR fuel. Recent results from experimentation at MIT, Halden and Studvik suggest that a galvanic coupling drives the phenomenon between the cladding and the adjacent material. However, the actual processes involved are not understood. One key parameter that would help in the understanding of the phenonenon would be a measurement of the actual corrosion current between fuel cladding and adjacent materials in the actual in-reactor environment. The limitations placed on the burn-up of uranium oxide fuel corelates to the amount of corrosion seen through a directly measurable oxide thickness on the waterside of the zirconium alloy cladding. This oxide corrosion product directly correlates to distance from structure components, leading the effect commonly referred to as shadow corrosion. In recent experiments, Studvik determined that there are large ECP differences associated with Inconel and zirconium alloys that correlate to increased galvanic current density when the materials are coupled. In this thesis research, four electrode pairs wre used to measure galvanic cirrent densities in the irradiation environment:Pt-Pt, Zircalloy (Zr-2), Inconel (X-750)-Pt, and Zr-2-X-750. To determine the changes in the coolant water conductivity dus to the presence of radiolysis products, electrochemical potential mesurements of Pt-Pt coupled electrodes were analyzed. Finally, attempts to characterize the observed oxide behavior using measurement from Electrochemical Impedance Spectroscopy (EIS), also known as Alternating Current Impedance, were conducted. Through the measurements taken, analysis of the mechanisms potentially causing the shadow corrosion phenomenon was conducted. The results of the observations included: Measurement of increased conductivity of coolant water correlating to increases in reactor power, measurement of increased galvanic current measurements correlating to increases in reactor power.
10
Kear, Gareth. "Electrochemical corrosion of marine alloys under flowing conditions." Thesis, University of Portsmouth, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369433.
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Heeg, Bauke. "An electrochemical and SHG study of corrosion inhibition." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.625055.
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12
Ismail, Mohammad. "Electrochemical chloride extraction to halt corrosion of reinforcement." Thesis, Aston University, 1998. http://publications.aston.ac.uk/14158/.
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This thesis presents results of experiments designed to study the effect of applying electrochemical chloride extraction (ECE) to a range of different hardened cement pastes. Rectangular prism specimens of hydrated cement paste containing sodium chloride at different concentrations were subjected to electrolysis between the embedded steel cathodes and external anodes of activated titanium mesh. The cathodic current density used was in the range of 1 to 5 A/m2 with treatment periods of 4 to 12 weeks. After treatment, the specimens were cut into sections which were subjected to pore-solution expression and analysis in order to determine changes in the distribution of free and total ionic species. The effect of the ECE treatment on the physical and microstructural properties of the cements was studied by using microhardness and MIP techniques. XRD was employed to look at the possibility of ettringite redistribution as a result of the accumulation of soluble sulphate ions in the cement matrix near the cathode during ECE. Remigration of chloride which remains after the ECE treatment and distribution of other ions were studied by analysing specimens which had been stored for several months, after undergoing ECE treatment. The potentials of the steel cathodes were also monitored over the period to detect any changes in their corrosion state. The main findings of this research were as follows: 1, ECE, as applied in this investigation, was capable of removing both free and bound chloride. The removal process occurred relatively quickly and an equilibrium between free and bound chlorides in the specimens was maintained throughout. At the same time, alkali concentrations in the pore solution near the steel cathode increased. The soluble sulphate ionic concentration near the cathode also increased due to the local increase in the pH of the pore solution. 2, ECE caused some changes in physical and microstructural of the cement matrix. However these changes were minimal and in the case of microhardness, the results were highly scattered. Ettringite in the bulk material well away from the cathode was found not to increase significantly with the increase in charge passed.3, Remigration of chloride and other ionic species occurred slowly after cessation of ECE with a resultant gradual increase in the Cl-/OH- ratio around the steel.4, The removal of chloride from blended cements was slower than that from OPC.
13
Powers, John W. "Neural networks : an application to electrochemical noise data." Virtual Press, 1997. http://liblink.bsu.edu/uhtbin/catkey/1045629.
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Neural networks were applied to the analysis of electrochemical noise data. Electrochemical noise is defined as the fluctuations in either current or potential with time for a metal which is immersed in a conductive solution. This data is of interest because of its relationship to particular corrosion processes. Specifically, a system which is experiencing uniform corrosion will produce a different noise signal than one which is experiencing localized (perforation) corrosion. The economic effects of corrosion are significant and methods which improve the ability to detect, measure and predict corrosion would be extremely valuable.Two series of experiments were conducted. The data for both series were collected from aluminum samples immersed in various aqueous solutions. The series differed from each other in the configuration and programming of the potentiostat which collected the data. The first series only dealt with potential noise while the second series dealt with both potential and current noise. Auxiliary parameters, such as the pH and chloride concentration of the solutions were used in the second series. The first series studied data from only two solutions, while the second series included six solutions.It was possible for neural networks to correctly categorize systems in Series 1 according to the class of corrosion being observed (uniform or perforating). Appropriate data transformation steps were required to effect these classifications and it was also observed that many of these data transformations would lead directly to categorization without the use of a neural network.The additional data collected in Series 2 allowed a more complex analysis. Neural networks were able to simultaneously predict both the propensity towards localized corrosion and the metal dissolution rate. This application demonstrated the power of neural networks.Several types of neural networks and learning algorithms were included in this study. The two systems used most were a backpropagation (multi-layer perceptron) and a radial basis system. Comparisons of the various network systems with regard to speed and accuracy were made.Department of Mathematical Sciences
14
Tan, Yong-jun. "Electrochemical studies on carbon dioxide corrosion and its inhibition." Curtin University of Technology, School of Applied Chemistry, 1996. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=11433.
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This thesis mainly concerns the application of electrochemical impedance spectroscopy (EIS) and electrochemical noise analysis (ENA) to the study of CO(subscript)2 corrosion of mild steel and its inhibition. The primary focus is on the use of EIS and ENA to monitor inhibitor film performance and to evaluate inhibitor film persistency.EIS was shown to be a suitable technique to study CO(subscript)2 corrosion product scale, and inhibitor films. The formation and deterioration of protective scales and inhibitor films is found to be accompanied by characteristic spectral changes and a rapid change in electrode impedance. EIS data were used to calculate corrosion related parameters such as the resistances and capacitances of inhibitor layers, and the charge transfer resistance and double layer capacitance. These parameters were used to analyse inhibitor mechanisms, determine corrosion rates and the persistence of inhibitor films.ENA is also a suitable technique to monitor the formation and deterioration of inhibitor films. It has the advantage of being able to monitor rapid processes which occur within one second. Several technical and theoretical developments were made in this thesis including the development of a new method of instantaneous corrosion rate measurement to study fast corrosion processes (the continuous noise resistance calculation method). Experimentally, the noise resistance was confirmed to be similar to linear polarisation resistance in the systems studies. The theoretical background and the advantages and disadvantages of the ENA technique are also discussed.Corrosion product scales formed under different conditions were investigated using EIS and surface analysis techniques. Temperature, pressure and exposure time were confirmed to be the important factors influencing the degree of protection given by the scale. The morphology of corrosion scales ++showed an obvious correlation to their protective ability. Electron microscopy revealed two types of crystal structures on corroded steel coupons. The smaller crystals associated with one of these structures was found to contribute most to corrosion protection.Several typical CO(subscript)2 corrosion inhibitors, including an imidazoline and a quaternised amine, were studied by EIS. A multi-layer model was employed to explain the EIS characteristics and self-repairing ability of imidazoline films. A quaternised amine film is most probably a physically or electrostatically adsorbed molecular layer which forms rapidly and desorbs easily.The deterioration of films, formed by commercial batch treatment inhibitors, was found to occur in three stages which were indicated or characterised by Bode phase-angle plots. A method to determine inhibitor film persistency was developed. This method is based on determining the three stages of inhibitor film deterioration, and the continuous measurement of corrosion rate, which is accessible at the second and third stages of film deterioration.
15
Husain, Adel Abdulmajeed. "Paint coated steel in Kuwaiti corrosion environment : surface corrosion mapping & electrochemical impedance spectroscopy." Thesis, Imperial College London, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336601.
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Deva, Yashika Poorvi. "Slug flow induced corrosion studies using electrochemical noise measurements." Ohio : Ohio University, 1995. http://www.ohiolink.edu/etd/view.cgi?ohiou1179513355.
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Xu, Yan. "Electrochemical behaviour of galvanic corrosion cells beneath organic coatings." Thesis, University of Oxford, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542999.
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Airey, K. "An electrochemical and analytical study of iron corrosion inhibitors." Thesis, University of Newcastle Upon Tyne, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303326.
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Kelly, Brett. "Electrochemical Method for Characterization and Ranking of Corrosion Inhibitors." Thesis, North Dakota State University, 2017. https://hdl.handle.net/10365/28657.
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One of the most cost-effective methods in mitigating corrosion effects is through the use of corrosion inhibitors. This work studied the performance of eight organic inhibitors on mild steel substrate through electrochemical characterization techniques, with the primary goal of incorporating a screening process to sift through the large selection of potential inhibitors without having to fully characterize them. The test methodology developed was successful at screening the potential corrosion inhibitors through linear polarization resistance (LPR) testing in NaCl electrolyte, narrowing the collection of inhibitors to the three most-promising chemicals, adrenalone, 3,4-dihydroxyphenylacetic acid and dopamine. The screened inhibitors proved effective in HCl electrolyte, reducing the corrosion rates of mild steel by over 85%. X-ray photoelectron spectroscopy (XPS) and quartz crystal microbalance (QCM) testing were used to confirm surface adsorption of the molecules to the substrate, indicating the formation of a protective barrier film as the means of corrosion protection.
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Morris, Howard. "The electrochemical behaviour of aluminium-based alloys." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302995.
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Sundaram, S. K. "Corrosion and electrochemical protection of molybdenum and molybdenum disilicide in molten silicate glass environments." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/18906.
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Chinthala, Sai Prasanna Prasanna. "Study of Corrosion Inhibitors for Reinforcement Corrosion of Low Carbon Steel in Simulated Pore Solution." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1555601685519345.
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Samaranayake, Chaminda Padmal. "Electrochemical reactions during ohmic heating." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1070303083.
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De, La Fuente Frederick G. "A Rubric for Electrochemical Testing of Metallic Biomaterials." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1286.
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Corrosion is a major factor for the failure of metallic medical implants. Testing a metal’s suseptability to corrosion prior to implantation is key to a successful implantation. Electrochemical processes were used in this study to evaluate the characteristics of corrosion of both AISI 316 stainless steel and titanium alloy Ti6Al4V, welded and non-welded. Linear, potentiodynamic, and cyclic polarization curves were produced by the PARC 2273 potentiostat showing the corrosion tendencies of the metals in four unique solutions 3.5% NaCl, 0.35% NaCl, phosphate buffered saline solution (PBS), and Butterfield phosphate buffered solution (BPS). The concentration of chloride ions in solutions affected the passivation current (Ipassive) and the passivation range of both AISI 316 and Ti6Al4V. In general, larger concentrations of the chloride ions increased the passivation current and decreased the passivation range. Both AISI 316 and Ti6Al4V exhibited passive behavior. Ti6Al4V proved to be the more corrosion resistant metal in the test solutions, showing the ability to repassivate and resist pitting.
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Zheng, Yougui. "Electrochemical Mechanism and Model of H2S Corrosion of Carbon Steel." Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1426864990.
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Ajayi, Fredric. "Mitigating corrosion risks in oil and gas equipment by electrochemical protection : top of the line corrosion." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/mitigating-corrosion-risks-in-oil-and-gas-equipment-by-electrochemical-protection-top-of-the-line-corrosion(550870a4-9373-4872-a076-a52f48a5a4f2).html.
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This study investigated the corrosion processes at the top and bottom of carbon steel pipelines transporting wet gases, and studied possible chemical mitigation strategies. First, immersion tests were carried out using carbon steel to study the effects of de-aeration with high purity nitrogen gas on the corrosion rate. Secondly, the corrosion rate was assessed for varying chloride ion concentrations in an aerated environment. In general, increasing de-aeration time changes the corrosion mechanism from mass transfer oxygen reduction to water reduction reaction. However, oxygen solubility controlled the corrosion process in aerated solution containing different chloride ion concentrations. A special two-electrode cell was designed for the top of the line corrosion (TLC) electrochemical measurements but a conventional three electrode cell was used for the bottom of the line corrosion (BLC) measurements. The TLC rate increases with temperature, and X-Ray Diffraction (XRD) confirmed the presence of chukanovite {Fe2(CO3)(OH)2}and possibly ferrous carbonate corrosion products at 40oC and 60oC respectively. However, for the BLC, the cementite phase remained on the metal surface after preferential dissolution of the ferrite phase in the carbon steel. Addition of acetic acid (HAc) locally dissolved the initially FeCO3 film formed on the metal surface, causing local corrosion damage. Addition of methyl di ethanol amine (MDEA) as a pH stabiliser reduced TLC and BLC rates due to enhanced stability of FeCO3 at pH 5.7-6.3. When Zn2+ ions were added as ZnCl2, both Fe2O3 and ZnCO3 were formed at reduced corrosion rate. Whenever FeCO3 film was damaged/dissolved by HAc addition of neither pH stabiliser; MDEA nor hydrate preventer; mono ethylene glycol (MEG) could not re-establish a protective film on the metal surface. The following organic inhibitors were investigated as potential mitigators of TLC: 2-mercaptobenzimidazole (2MBI), 2-amino-5-ethyl-1,3,4-thiodiazole (AETDA), 2-phenyl-2-imidazoline (2PI), dicyclohexylamine (DHA), and a commercial inhibitor formulation (CI-A). The inhibition efficiency (IE%) was found to increase in the order CI-A > 2MBI > AETDA > DHA. Their efficiency increases (except DHA) with inhibitor concentrations both at top and bottom of the line. 2MBI and CI-A behaved as mixed inhibitors but AETDA behaved as cathodic inhibitor, all were best fitted to a simple Langmuir adsorption isotherm. However, IE% of DHA decreased at higher inhibitor concentrations. Surprisingly, 2PI inhibitor increased the corrosion rate, and the corrosion rate further increased with increase inhibitor concentrations. Weight loss measurements results of TLC are also presented which showed lower inhibition efficiency for all the inhibitors investigated compared with electrochemical measurements in similar environments. The free energy of adsorption (∆Goads values for 2MBI and AETDA are around -36kJ.mol-1 while for CI-A the value was -15kJ.mol-1 (-7kJ.mol-1 in the presence of HAc). This is evidence for adsorption of 2MBI and AETDA on the metal surface by chemisorption with CI-A by physisorption. XPS analysis confirmed the presence of FeCO3 and FeOOH as corrosion products in the brine solution in the absence and presence of HAc containing different corrosion inhibitors.
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Zou, Feng. "Localized electrochemical impedance technique for the study of corrosion processes /." Stockholm : Tekniska högsk, 1998. http://www.lib.kth.se/abs98/zou1218.pdf.
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Price, Stephen. "Electrochemical investigations of the fretting corrosion of offshore structural materials." Thesis, University of Sunderland, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.290927.
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Al-Kaseasbeh, Qusay Adel. "Electrochemical Investigation of Corrosion Resistance of Weldments in Steel Bridges." Thesis, North Dakota State University, 2015. https://hdl.handle.net/10365/27676.
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Welding is commonly used for connecting steel components in steel bridge fabrication and construction. Welding processes change the microstructures, properties of surrounding steel and its surface texture. In this study, an investigation of corrosion behavior of steel bridge welds was performed under simulated corrosive environments in the laboratory. Four electrochemical tests: a) open circuit potential, b) Rp/Ec Trend, c) electrochemical impedance spectroscopy and d) potentiodynamic polarization, were identified and conducted to gain fundamentals to weldment corrosion in two commonly used bridge steels (A572 and A588). In addition, three coating systems (3-coat, Calcium sulfonate alkyd, and metallizing coating) in steel bridges were deposited on the bridge steels. Test results revealed that the bridge steel welds exhibit higher corrosion initiation over base metals, regardless the types of steel or coating. The protective coating systems can delay the corrosion initiation at the welds, thus enhancing the corrosion resistance of bridge steel welds.
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Otsuka, Nobuo. "Electrochemical study of hot corrosion of Ni at 900 C." The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu1346164361.
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Eckermann, Fabian. "Microscopic structural and electrochemical aspects of Al-Mg-Si corrosion." Aachen Shaker, 2008. http://d-nb.info/989398706/04.
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Huang, Tsai-Shang. "On the intergranular corrosion of 7xxx aluminum alloys." Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1133365169.
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Hoyle, Rene Alwyn Stuart. "The efffect of chlorinated hydrocarbons on the corrosion resistance of austenitic stainless steels in chloride solutions." Thesis, University of Sunderland, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246188.
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Karavai, Olga. "Mapping local corrosion parameters using SVET and SIET." Doctoral thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22052.
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Doutoramento em Ciência e Engenharia de MateriaisLocalized corrosion, i.e., corrosion confined to local regions, is difficult to predict and control. In general, it appears as a result of heterogeneities, either in the metal or in the corrosive environment. One of the phenomenological features of localised corrosion is the development of specific environments close to active sites. In practice, the micro-environment near the metallic surface is different from that of the bulk medium and varies with time and conditions of the system under study. Localized electrochemical techniques based on the use of microelectrodes are well suited for in situ sensing the distribution of potential, current and chemical species in active zones, pores or defects. Most of the published work dealing with microelectrodes in corrosion is mainly exploratory and their use in a regular basis is still rare in corrosion research. This work presents the development and application of microelectrodes as experimental tools capable to assess local electrochemical reactions on metallic substrates immersed in aggressive solutions. Traditional electrochemical techniques used in corrosion research give the average response of the global activity of the whole surface not discriminating local effects and local chemistry. Therefore they are unable per si to properly characterize localized phenomena and the corresponding corrosion, inhibitive mechanisms and, sometimes, even to select the best protection methods. It is important to know local parameters such as pH, micro-galvanic effects, concentration of oxidizing (like O2) and aggressive (like Cl-) species, and formation of surface films. The Scanning Vibrating Electrode Technique (SVET) was used for local measurements of ionic currents in solution. The technique detects the potential distribution in solution associated to ionic currents in solution. For the analysis of the chemical species involved in the corrosion process, electrochemical microsensors were used in SIET (Scanning Ion Selective Electrode Technique) mode. Microelectrodes sensitive to pH, dissolved oxygen and metal cations (namely, Mg2+, Zn2+ and Cu2+) were developed and characterized. Work was also done with microeloectrodes sensitive to Al3+, but with less success. Then, they were used for investigating the reactivity on defects and corrosion inhibition on coated aluminium and magnesium alloys, detecting the micro-distribution of chemical species in solution close to the corroding surface of Zn, Cu and a Zn- Fe galvanic couple specimens. ix Limitations and difficulties exist for the use of these techniques in corrosion research due to the inherent reactivity of corroding metals, with the formation of corrosion products and sharp changes of pH, O2 and ionic strength along the samples surface. In spite of the difficulties, the results presented here demonstrate that the SVET/SIET mapping gives useful information for the quantification of electrochemical processes at the micro-level. The data are of prime importance for the modelling and simulation of corrosion mechanisms, selection of new corrosion inhibitors and development of ‘‘smart” coatings that suppress the corrosion processes.
A corrosão localizada, i.e., corrosão confinada a locais específicos, é difícil de prever e controlar. Em geral, ocorre como resultado de heterogeneidades tanto no metal como no ambiente corrosivo. Uma das características da corrosão localizada é o desenvolvimento de ambientes específicos junto das zonas activas. Na prática, o micro-ambiente junto da superfície metálica é diferente do do seio da solução, variando com o tempo e com as condições do sistema em estudo. Técnicas electroquímicas localizadas baseadas na utilização de microeléctrodos são convientes para medir a distribuição de potencial, intensidade de corrente e espécies químicas em solução junto de zonas activas, poros ou defeitos. Muito do trabalho que existe publicado sobre microeléctrodos em corrosão refere-se a trabalho exploratório que permanece numa etapa preliminar. A aplicação de microeléctrodos em estudo de corrosão numa base rotineira é ainda rara. Este trabalho apresenta o desenvolvimento e aplicação de microeléctrodos como ferramentas experimentais capazes de aceder a reacções electroquímicas locais em substratos metálicos imersos em soluções agressivas. As técnicas electroquímicas tradicionais usadas no estudo de corrosão dão resposta média do processo global em toda a superfície da amostra sem distinguir efeitos locais e a química local. Não são, portanto, adequadas para a descrição detalhada dos mecanismos de corrosão localizada, de processos de inibição e, por vezes, para a selecção dos métodos de protecção mais adequados. É importante conhecer parâmetros locais, como pH, efeitos micro-galvânicos, concentração de espécies oxidantes (como O2) e agressivas (como Cl-), formação de filmes superficiais. Neste trabalho usou-se a técnica do eléctrodo vibrante de varrimento (SVET) para medições locais de corrente iónica em solução. A técnica detecta a distribuição de potencial em solução, associada à corrente iónica. Para a análise de espécies químicas envolvidas no processo corrosivo, foram usados microsensores electroquímicos no modo SIET (Técnica de Varrimento de Eléctrodo Selectivo de Iões). vii Foram desenvolvidos e caracterizados microeléctrodos sensíveis a pH, oxigénio dissolvido e catiões metálicos (nomeadamente, Mg2+, Zn2+ e Cu2+). Trabalhou-se também no desenvolvimento de microeléctrodos sensíveis a Al3+, embora com menos sucesso. Os microeléctrodos foram utilizados na investigação da corrosão e inibição em defeitos induzidos em revestimentos protectores aplicados sobre ligas de alumínio e de magnésio, e na detecção da micro-distribuição de espécies químicas em solução perto de eléctrodos de zinco, cobre e de um par galvânico Zn-Fe. Este trabalho revela também as limitações e dificuldades na aplicação destas técnicas ao estudo de corrosão devido à inerente reactividade do processo corrosivo, com formação de produtos de corrosão e grandes variações de pH, O2 e força iónica ao longo da superfície de amostra. Apesar das dificuldades, os resultados aqui apresentados demonstram que o mapeamento por SVET/SIET fornece informações muito úteis para a quantificação de processos electroquímicos à micro-escala. Os dados são de primordial importância para a modelação e simulação de mecanismos de corrosão, selecção de novos inibidores de corrosão e desenvolvimento de revestimentos anticorrosivos “inteligentes”.
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Siegwart, Michael. "The feasibility of electrochemical chloride extraction on prestressed concrete structures." Thesis, University of Ulster, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252423.
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Shao, Hong. "Electrochemical reactions on freshly generated surfaces of MgZn#." Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/18859.
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Mabbutt, S. J. "Investigation into corrosion protection by coatings using the electrochemical noise method." Thesis, University of Northampton, 2000. http://nectar.northampton.ac.uk/2981/.
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The Electrochemical Noise Method (ENM) monitors the small potential and current fluctuations that occur naturally in electrochemical cells. It is the least intrusive of all electrochemical techniques in common use. This work uses the Electrochemical Noise Method to investigate the corrosion protection afforded by organic coatings. A parameter called Noise Resistance (Rn) is derived from an Ohm law relationship using the potential noise (Vn) and current noise (In) values. The noise on the current and potential data sets is calculated as the standard deviation value. The work is divided into three areas. The first looked at coating systems in the intact state on the substrate. In general this part of the work has corroborated previous work where Rn values of >l x 10^7 ohms-cm^2 indicated protection of the substrate, correlating with DC resistance values of the coating. The second area of work investigated scribed coatings on the substrate. An important property of organic anti-corrosive coatings is the ability to protect the substrate at a break in the coating. In the scribed work the level of protection afforded at exposed metal by the coating was related to the Noise Resistance value. The third area of this investigation looked at novel ENM techniques to investigate organic coatings. Detached intact coatings were examined in a “U” tube test cell that can be used to simulate different conditions that may be encountered in service. Also a new technique was devised for obtaining ENM data from corrosion cells, this does not require the two separate substrate elements necessary for the more established methodology. The new technique has been called the Single Substrate (SS) technique to reflect this useful property. The technique could be used for in-situ monitoring of structures and it could be adapted for investigation of other situations such as reinforcement bars in concrete
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Buttrey, F. E. "Predictive corrosion testing of tin mill products using advanced electrochemical techniques." Thesis, Swansea University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636192.
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This thesis documents studies directed towards the development of electrochemical measurement procedures capable of quantifying corrosion resistance and/or the corrosion rate in Tin Mill products, and in particular steel food/beverage cans. Chapters 3 and 4 describe electrochemical studies carried out using commercially produced cans. Conventional corrosion evaluation techniques were compared with Electrochemical Impedance Spectroscopy (EIS) data. EIS was found to provide useful information regarding container corrosion performance, however statistical variation from can to can required the use of large sample populations unless cans could be conserved between measurements. This was achieved by the development of "sealed-in-electrodes", which were used to identify trends in can coating performance. Sealed-in-electrodes form the basis of a predictive corrosion test method, whereby short-term electrochemical measurements may be extrapolated to predict long-term corrosion performance. Conventional electrochemical techniques provide a surface averaged measurement of the corrosion performance of coated metals, giving no information regarding the spatial distribution of penetrative defect sites in the organic coating. For this reason, a novel method for defect detection was developed, exploiting the phenomenon of electrogenerated chemiluminescence (ECL) in conjunction with digital (CCD) photography. The development, optimisation and evaluation of techniques for the spatially resolved characterisation of penetrative coating defect populations using luminol ECL is described in chapters 5 - 7. A proposed mechanism and kinetic model for the ECL process is described in chapter 5. Chapter 6 describes the application of luminol ECL to the detection of induced defects in a polymer laminate material, and an estimation of the limits of the technique. Chapter 7 describes the application of luminol ECL to the detection of defect populations in commercially produced polymer laminate cans. ECL images were suitable for computerised image analysis, providing information on the frequency, size distribution and location of penetrative defects.
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Radford, G. J. W. "The marine corrosion and electrochemical characteristics of MARINEL copper nickel alloy." Thesis, University of Portsmouth, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310387.
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Tan, KengSoong. "Electrochemical analysis of the erosion corrosion of HVOF aluminium bronze coatings." Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274707.
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Xu, Weichen. "Synchrotron X-ray and electrochemical studies of pitting corrosion of iron." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5435/.
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Pitting corrosion of iron has been studied via artificial pits. Solid corrosion products were observed within the pit, which was characterised as disordered-carbon and Fe\(_3\)C, acted as diffusion barriers for metal ions and slightly increased the solution resistance. Its formation depends upon the interfacial potential. High purity iron was used to calculate an effective diffusion coefficient for metal ions (a combination of self-diffusion and electrical migration) in different MgCl\(_2\) concentrations. The contribution of self-diffusion increases with increasing MgCl\(_2\) concentration if Mg\(^2\)\(^+\) depletion in the pit is considered. The Tafel kinetics of iron dissolution in metal ion saturated solutions was studied in different MgCl\(_2\) concentrations. The Tafel slope (56 to 70 mV/decade) was independent of MgCl\(_2\) and FeCl\(_2\) concentration when FeCl\(_2\) is saturated. The effect of nitrate on the composition/structure of salt layers was characterised. The salt layer is composed of FeCl\(_2\).4H\(_2\)O in chloride-based solutions (isotropic in HCl and anisotropic in HCl with trace nitrate), and Fe(NO\(_3\))\(_2\).6H\(_2\)O in nitrate-based solutions. The dissolution behaviour of iron in chloride/nitrate solutions was studied. Dissolution is uniform under a salt layer, but crevice formation and surface roughening. Potentiodynamic measurements can induce abrupt dissolution/ passivation transitions, resulting in deep and localised attack.
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Grover, David J. (David Joseph). "Modeling water chemistry and electrochemical corrosion potential in boiling water reactors." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/39772.
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Divi, Suresh Chandra. "Electrochemical corrosion study of structural materials in complex multi-ionic solutions." abstract and full text PDF (UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3307140.
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Mohorich, Michael E. "Electrochemical corrosion behavior of AISI 4340 steel in multi-ionic solutions." abstract and full text PDF (UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1459436.
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Fasuba, Omoniyi. "Electrochemical corrosion evaluation of aluminium-based coating alternatives to cadmium plating." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/6730/.
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Electroplated cadmium has been employed for decades as a coating material to provide protection for steels against corrosion because of its combination of inherent corrosion resistance in atmospheric conditions, bi-metallic corrosion characteristics, lubricity and good electrical conductivity. However, it is a toxic metal and known carcinogenic agent, which is plated from an aqueous bath containing cyanide salts. For these reasons, the use of cadmium has been banned in Europe for most industrial applications. Nevertheless, the aerospace industry is still exempt due to stringent technical and safety requirements associated with aeronautical applications, until a reliable and acceptable replacement is found. Aluminium-based coatings are potential candidates to replace cadmium because of their low toxicity and high corrosion resistance in aggressive media. The corrosion properties of commercially available aluminium-based coatings: Al-Zn flake inorganic spin, Al-based slurry sprayed and arc sprayed Al coatings deposited on mild steel were investigated. Al, AlCr and AlCr(N) coatings deposited by Electron Beam Physical Vapour Deposition (EBPVD) technique on M2 and 17/4 PH steel substrates at 3000 C were also investigated. The range of electrochemical techniques used to evaluate the corrosion properties of the coatings include: Open-circuit Potential (OCP), Potentiodynamic Polarisation (PDP), Electrochemical Impedance Spectroscopy (EIS), Galvanic coupling and Electrochemical Noise (ECN) measurements. The structure and composition of the coatings were characterised by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) spectroscopy. For the commercially available Al-based coatings, the Al-based slurry coating exhibited an open-circuit potential closer to the mild steel substrate than other coatings, as well as a low corrosion current density and a more positive corrosion potential. In terms of galvanic compatibility with 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 cadmium. This behaviour confirms their superior cathodic protection capability and galvanic compatibility over other coatings. Good correlation between data from the ECN, OCP, potentiodynamic polarisation and EIS measurements was found; in particular electrochemical noise resistance (Rn) correlates well with polarisation resistance (RP) and corrosion current density (icorr). However, magnitudes of elements in EIS results vary widely when compared to those of the potentiodynamic polarisation tests. Furthermore, analysis of the current-potential noise time data reveals uniform corrosion for cadmium and Al-Zn flake inorganic coating, passivation for Al-based slurry sprayed coating and localised corrosion for arc sprayed Al coating. However, the polarisation results revealed localised corrosion for Al-Zn flake inorganic coating, indicating that the corrosion mechanism of the coating is mixed (i.e. both localised and uniform). For the EBPVD Al-based coatings, OCP and PDP measurements show that the incorporation of chromium and nitrogen in the coatings enhanced the corrosion resistance. However, this also resulted in the ennoblement of the corrosion potential, hence the AlCr and AlCr(N) PVD coatings deposited on M2 steel could not preserve their sacrificial character, while the same coatings deposited on 17/4 PH steel remained sacrificial with respect to the substrate. This difference is due to the respective open-circuit potential of the two substrates. Good agreement between data from the different electrochemical techniques was found. The AlCr(N) coatings show strong passivation, the AlCr coating deposited on M2 steel displayed localised form of corrosion, while its counterpart deposited on 17/4 PH corroded uniformly. This discrepancy lies in the difference in their coating morphology and Cr content. Thus, the corrosion behaviour of the EBPVD Al-coatings deposited on M2 steel is strongly dependent on the chromium and nitrogen content. Overall, the AlCr coating deposited on the 17/4 PH steel demonstrates combined barrier and sacrificial protection capacity. Characteristic charge, q and frequency of corrosion events, fn could not distinguish properly between the different types of corrosion associated with the EBPVD Al-based coatings, indicating that these parameters cannot be relied upon as true indicators of corrosion mechanisms. Finally, it was shown that utilising the localisation index (LI) and the roll-off slope of power spectra density (PSD) to discriminate between different types of corrosion needs further investigation, especially with regards to passive systems, where ECN measurements are often contaminated with extraneous noise sources, leading to false estimates of values obtained from these parameters.
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Halsall, John Frederick. "The prevention of biological corrosion and fouling of metals : a study of corrosion processes and the electrochemical methods of controlling corrosion and fouling." Thesis, Bangor University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318073.
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Cromie, James Alexander. "Modelling the electrochemical rehabilitation of chloride contaminated reinforced concrete bridge structures." Thesis, University of Ulster, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342317.
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Akhoondan, Mersedeh. "Corrosion assessment of mechanically formed aluminized steel." [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0002248.
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Langford, Paul Edwin. "Electrochemical characteristics of steel in cement systems." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241171.
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Kahl, Michael S. "Electrochemical Synthesis and Applications of Layered Double Hydroxides and Derivatives." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc804917/.
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Layered double hydroxides (LDH) are a class of anionic clay with alternating layers of positive and negative charge. A metal hydroxide layer with divalent and trivalent metals with a positive charge is complemented by an interlayer region containing anions and water with a negative charge. The anions can be exchanged under favorable conditions. Hydrotalcite (Mg6Al2(OH)16[CO3]·4H2O) and other variations are naturally occurring minerals. Synthetic LDH can be prepared as a powder or film by numerous methods. Synthetic LDH is used in electrode materials, adsorbents, nuclear waste treatment, drug delivery systems, water treatment, corrosion protection coatings, and catalysis. In this dissertation Zn-Al-NO3 derivatives of zaccagnaite (Zn4Al2(OH)12[CO3]·3H2O) are electrochemically synthesized as films and applied to sensing and corrosion resistance applications. First, Zn-Al-NO3 LDH was potentiostatically electrosynthesized on glassy carbon substrates and applied to the electrochemical detection of gallic acid and caffeic acid in aqueous solutions. The modified electrode was then applied to the detection of gallic acid in green tea samples. The focus of the work shifts to corrosion protection of stainless steel. Modified zaccagnaite films were electrodeposited onto stainless steel in multiples layers to reduce defects caused by drying of the films. The films were deposited using a step potential method. The corrosion resistance of the films in a marine environment was investigated while immersed in 3.5 wt.% NaCl environments. Next modified zaccagnaite films were potentiostatically electrodeposited onto stainless steel followed by a hydrophobization reaction with palmitic acid in order to prepare superhydrophobic (>150° contact angle) surfaces. Each parameter of the film synthesis was optimized to produce a surface with the highest possible contact angle. The fifth chapter examines the corrosion resistance of the optimized superhydrophobic film and a hydrophobic film. The hydrophobic film is prepared using the same procedure as the superhydrophobic film except for a difference in electrodeposition potential. The corrosion resistance of these films is investigated in a simulated marine environment (3.5 wt.% NaCl) for short and extended durations. The last chapter summarizes the previous chapters and suggests future directions for this work.