Journal articles: 'Anodes – Corrosion'

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Huang, Yan Bin, Gao Wei Song, Hua Dong Ding, Xue Bin Liu, and Xin Hai Shao. "Cathodic Protection Performance of Al-Zn-In-Mg-Ga-Mn Sacrificial Anode." Advanced Materials Research 214 (February 2011): 296–300. http://dx.doi.org/10.4028/www.scientific.net/amr.214.296.

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The solubility and cathodic protection performance of Al-Zn-In-Mg-Ga-Mn sacrificial anode in natural corrosion and self-discharge experiment was studied using electrochemistry impedance spectrum technology, weight-loss measurement and SEM. The results show that the corrosion rate of 7A52 was decreased under the protection of sacrificial anodes in the self-discharge experiment, and sacrificial anodes dissolved uniformity due to the effect of active location, the corrosion products are easy to shed. Only location corrosion occurs on the sacrificial anode’s surface which is influenced by corrosion products and oxide film in natural corrosion experiment.

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Nakisa, Shima, Naghi Parvini Ahmadi, Javad Moghaddam, and Habib Ashassi-Sorkhabi. "Study of corrosion behavior of virgin and recycled Pb anodes used in zinc electrowinning industry." Anti-Corrosion Methods and Materials 67, no. 6 (October 16, 2020): 529–36. http://dx.doi.org/10.1108/acmm-04-2017-1787.

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Purpose The composition and corrosion behaviors of recycled and virgin Pb anode were investigated in industrial zinc electrowinning solution with different methods. The purpose of this study is the illustration of good anticorrosion activity of virgin Pb anodes compared to recycled one in industrial operation, while the compositions of both of them are the same which obtained from quantmetry method. Design/methodology/approach Its corrosion properties and electrocatalytic activity toward oxygen evolution reaction were appraised using potentiodynamic polarization, electrochemical impedance spectroscopy, galvanostatic polarization and ionic equilibrium methods. In addition, composition of anodes investigated with X-ray photoelectron spectroscopy (XPS) method. The surface composition of samples was studied via X-ray diffractogram (XRD). Findings The results indicate that the anodes display different anodic behaviors during the galvanostatic polarization. Virgin Pb anode shows a “potential reduction” about 320 mV lower than recycled Pb anode after 6 h of polarization; also, the stable potential after 72 h for virgin Pb anode is 100 mV lower than recycled Pb anode. Also, The XPS results show a trace amount of Cl in recycled anodes which cause the more corrosion activity. XRD results indicate that virgin Pb anodes have been covered by more oxides than recycled anodes after 72 h of electrowinning. Originality/value The treatment of corrosion behavior by virginity has not been detected by any researchers yet. Therefore, it is imperative to study the corrosion behavior and exact composition analysis of virgin and recycled Pb anodes to comprehension of them. This paper fulfills this need.

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Yang, Mingkun, Yan Liu, Zeyao Shi, Xiaodan Lv, Bin Liu, and Luyi Sun. "Study on the Electrochemical Behavior of Al-6Zn-0.02In-1Mg-0.03Ti Sacrificial Anodes for Long-Term Corrosion Protection in the Ocean." Corrosion 76, no. 4 (February 11, 2020): 366–72. http://dx.doi.org/10.5006/3404.

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After 10 y of service in the ocean, the long-term performance of Al-6Zn-0.02In-1Mg-0.03Ti aluminum alloy sacrificial anodes for steel piles was characterized by mass loss in addition to optical and electron microscopy analysis. The electrochemical behavior was conducted by open-circuit potential with potentiodynamic and potentiostatic polarizations. The results showed that cathodic protection potential was in the range of −0.960 VCSE to −1.103 VCSE. The corrosion type and consumption rate of the alloy anode were related to the output current. In harsh corrosion environments, the alloy anode showed uniform corrosion and lost more mass due to voltage output, therefore more current is needed to fulfill cathodic protection. Otherwise, localized corrosion and less mass loss were observed. The alloy anodes were covered by marine creatures and corrosion product. The corrosion product contained amorphous Al(OH)3 and MgAl2(CO3)(OH)·xH2O which became more crystalline from outside to inside of the alloy anode. A translucent corrosion product was found on the alloy anode surface which contained amorphous Al(OH)3·xH2O with S, along with AlxCly(OH)z·mH2O. The electrochemical performance of the alloy anode was strongly reduced by the coverage of corrosion product. Consequently, the open-circuit potential of the alloy anode increased and the output current decreased. The effect of corrosion product thicknesses on the anodic activation is not remarkable.

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Shamsudin, Shaiful Rizam, Azmi Rahmat, Mahdi Che Isa, Mohd Nazree Derman, and Abdul Razak Daud. "Electrochemical Corrosion Behaviour of Mg-(Ca,Mn) Sacrificial Anodes." Advanced Materials Research 795 (September 2013): 530–34. http://dx.doi.org/10.4028/www.scientific.net/amr.795.530.

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The aim of the study is to identify the effect of Ca in Mg-Mn alloy on electrochemical corrosion behavior for the development of high performance sacrificial anode. Mg alloys were fabricated by casting technique under an inert atmosphere. 0.35 ~ 1.11 wt.% of Ca were added as alloying element. The finding shows that the addition of small Ca in Mg-Mn anodes was found not significantly affecting the corrosion rate. However, small content of Ca was as much as necessary improving electronegativity of open circuit potential and modifying anodic polarization in promoting the instabilities of surface passive layer hence results in the further dissolution process between ion and alloy species underneath. No passivation occurs on the standard samples. Pitting profile only occur on Mg-Mn anode that has lower Ca content (0.35 wt. %). An XRD result shows no present of Mg2Ca phase on the as-cast anode containing 1.11 wt. % Ca. As a conclusion, the influence of small content of Ca was profoundly modifying electrochemically behaviour of Mg containing Mn anodes except corrosion rate.

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López Miguel, Abraham, José Trinidad Pérez Quiroz, Raúl Ortega-Borges, Miguel Martínez Madrid, Mariela Rendón Belmonte, Juan Manuel Salgado López, Gabriel Trejo, and Yunny Meas-Vong. "Comparative Study between NiCoB and IrO2-Ta2O5/Ti Anodes for Application in Impressed Current Cathodic Protection (ICCP)." Coatings 10, no. 3 (February 25, 2020): 199. http://dx.doi.org/10.3390/coatings10030199.

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In an impressed current cathodic protection system (ICCP) to protect structures against corrosion, the efficient operation depends on the proper selection of the electrodes, particularly the anode, chosen considering the structure to be protected and the environment in which it is located. The nature and overpotential of the anodic reaction determine the operation costs of an ICCP system so that proper anode selection is critically important for an ICCP system to function efficiently. Commercial anodes based on titanium substrates coated with iridium–tantalum oxide mixtures (IrO2-Ta2O5/Ti) are frequently used for this purpose due to low operating overpotentials. However, the gradual passivation of its surface limits its useful life and increases its operating costs, so it is necessary to seek competitive alternatives for its replacement. This study aimed to determine the feasibility of using carbon steel substrates coated with nickel/cobalt/boron (NiCoB/CS) as a viable low-cost alternative to replace IrO2-Ta2O5/Ti anodes in ICCP systems. Comparison between the electrochemical behavior and the corrosion resistance of both types of electrodes shows that the NiCoB/CS anode shows a good electrocatalytic activity and a higher corrosion resistance than IrO2-Ta2O5/Ti coated anodes, indicating that the NiCoB/CS anodes are promising low-cost candidates for ICCP systems.

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Yuan, Xue Tao, Xu Dong Lv, Yu Gao Zhou, Zhi Qiang Hua, Yang Lei, Lei Wang, and Tao Li. "Anodic Behavior of Pb-Ag-Ca-Sr Alloy in Zinc Electrowinning." Advanced Materials Research 790 (September 2013): 85–89. http://dx.doi.org/10.4028/www.scientific.net/amr.790.85.

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Over potentials for oxygen evolution reaction, corrosion rate, surface product after polarization and microstructure before and after polarization of Pb-0.2%Ag-0.08%Ca-0.05%Sr quaternary anode in zinc electrowinning were studied and compared with Pb-0.6%Ag binary anode. The results show that over potentials for oxygen evolution reaction on Pb-0.6%Ag and Pb-0.2%Ag-0.08%Ca-0.05%Sr anodes are 675 mV and 790 mV, respectively, while the corrosion current density are 8.2μAcm-2 and 20.1μAcm-2. The surface structure after experiment of in Pb-Ag anodes is dense and tightly attached to the base, while the surface of Pb-Ag-Ca-Sr is loose and porous. The phases of the surface are PbO2, PbSO4 and MnO2 on both anods.

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Zhong, Xiao Cong, Bo Hong, Yan Hong Li, Liang Xing Jiang, and Yan Qing Lai. "The Effects of Nd on Lead Anode for Zinc Electrowinning." Advanced Materials Research 581-582 (October 2012): 1115–18. http://dx.doi.org/10.4028/www.scientific.net/amr.581-582.1115.

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A detailed investigation of the effects of Nd on the microstructure, mechanical properties and electrochemical properties of lead anode in 160g.L-1 at 35°C was carried out. Galvanostatic polarization and Chronopotentiometry (CP) were used to study the electrochemical behavior ( such as anodic potential, corrosion rate and the composition of passive film) of the Pb and Pb-Nd anodes. The metallographic structure and passive film morphology of Pb and Pb-Nd anodes were observed and analyzed using polarizing microscope and scanning electronic microscopy (SEM), respectively. The experimental results show the grains become smaller and aggregation of PbxNdy become severe as the content of Nd increases. The addition of Nd enhances the formation of PbO2, inhibits the formation of PbSO4 and PbO and reduces the anodic potential. However, Holes presenting on rough passive film of high Nd content Pb-Nd anodes accelerate the corrosion.

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Zhu, Yu Ping, Ye Dong He, and De Ren Wang. "High Temperature Corrosion of M-40Cr-0.5Ce Alloys as Inert Anodes in Aluminium Electrolysis." Materials Science Forum 696 (September 2011): 254–59. http://dx.doi.org/10.4028/www.scientific.net/msf.696.254.

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Fe-40Cr-0.5Ce and Ni-40Cr-0.5Ce alloys prepared by vacuum melting have been studied as inert anodes in aluminium electrolysis. High temperature corrosion of these alloy anodes was conducted in cryolite-alumina electrolytes at anodic current density of 0.5 A/cm2, at 800°C and 900°C for 10h respectively. It is found that a Cr2O3 scale was selectively formed on the surface of Ni-40Cr-0.5Ce anode at 900°C, corresponding to excellent corrosion resistance during aluminium electrolysis and higher purity of aluminium product. While a composite oxide film was developed on the surface of Fe-40Cr-0.5Ce anode at 800°C. The formation of Cr2O3 scale is controlled by both of the dissolving rate of Cr2O3 scale in electrolyte and the diffusing rate of Cr in alloys, so the M-Cr alloys require a high content of Cr for inert anodes application.

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Osundare, Ayomide, Daniel Toyin Oloruntoba, and Patricia Popoola. "Development of carbon anode for cathodic protection of mild steel in chloride environment." Anti-Corrosion Methods and Materials 65, no. 2 (March 5, 2018): 158–65. http://dx.doi.org/10.1108/acmm-07-2017-1817.

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Purpose The purpose of this paper is to develop technically efficient and economically effective sacrificial anodes that can be used for cathodic protection (CP) of pipelines in marine environment and fill the knowledge gap in the use of carbon anodes for CP. Design/methodology/approach A sacrificial anode was produced via sand casting by adding varying weight-percent of coal and ferrosilicon to a constant weight-percent of grey cast iron. The hardness of the produced anodes was evaluated using a Rockwell hardness tester. The microstructure of the anodes was observed with scanning electron microscope/energy-dispersive spectroscopy (SEM/EDS). X-ray diffraction (XRD) was used to study the phases present. A potentiostat was used to assess the corrosion behaviour of the produced anodes and mild steel in 3.5 Wt.% NaCl solution. Findings The SEM results showed that some anodes had interdendritic graphite formation, while others had pronounced graphite flakes. The EDS analysis showed carbon and iron to be the prominent elements in the anode. Anodes Bc, B2 and B5 with a corrosion rate of two order of magnitudes were observed to have similar dendritic structures. Anode B4 is the most electronegative with an Ecorr of −670.274 mV Ag/AgCl and a corrosion rate of 0.052475 mmpy. The produced anodes can be used to protect mild steel in the same environment owing to their lower Ecorr values compared to that of mild steel −540.907 mV Ag/AgCl. Originality/value Alloying has been majorly used to improve the efficiency of sacrificial anodes and to alleviate its setbacks. However, development of more technically efficient and economically effective sacrificial anodes via production of composite has not been exhaustively considered. Hence, this research focuses on the development of a carbon based anode by adding natural occurring coal and ferrosilicon to grey cast iron. The corrosion behaviour of the produced anode was evaluated and compared to that of mild steel in marine environment.

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Zhang, Wei, Sanae Haskouri, Georges Houlachi, and Edward Ghali. "Lead-silver anode behavior for zinc electrowinning in sulfuric acid solution." Corrosion Reviews 37, no. 2 (March 26, 2019): 157–78. http://dx.doi.org/10.1515/corrrev-2018-0007.

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AbstractIn recent years, a renewed interest in studying the electrochemical corrosion behavior of lead anodes during zinc electrowinning is probably due to the particularly high sulfuric acid concentrations in zinc electrolyte where lead alloy anodes have high cell voltage and high corrosion rate of lead. The high corrosion rate of lead alloy resulted in Pb contamination on zinc deposit. In zinc electrometallurgy, the electrolyte from a zinc-rich ore contains a significant amount of Mn2+. Mn2+ in the zinc electrolyte results in forming an oxide film on lead anodes during electrolysis. Pb-0.7% Ag anode is generally used in the zinc industry. To improve the technical performance and decrease product cost, other anodes, such as Pb-Ca or Pb-Ag-Ca or Pb-Ag-Ti or Pb-Ag-Se alloys were tested. Till now, none of them has succeeded in the substitution of Pb-Ag anodes in the zinc electrowinning. As an alloying element, silver in small quantities is considered because of the benefits that generates on the anode during electrolysis. During zinc electrolysis, lead dissolution into the zinc electrolyte can be harmful to the quality of zinc deposit. However, the lead silver alloy anode can decrease the lead content in the zinc deposit by pre-treated methods such as blasting and preconditioning.

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Dodds, Wayne, Christian Christodoulou, and Chris Ian Goodier. "Long-Term Performance of Hybrid Anodes for Cathodic Protection of Reinforced Concrete." MATEC Web of Conferences 199 (2018): 05003. http://dx.doi.org/10.1051/matecconf/201819905003.

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The long-term performance of hybrid anode corrosion protection systems (UK invention disclosed in Patent GB2426008B) was investigated on six bridge structures as part of a holistic approach to corrosion risk management, using the performance criteria in ISO BS EN 12696:2016. The aim of the study was to review the effectiveness of current design approaches to meet the residual service life when the anodes are operating in the galvanic phase. This was achieved by analysing data on the general condition of the structures, the ongoing performance of the installed hybrid anodes, and assessing the subsequent corrosion risk. It was found that the six structures were generally in good condition, 1 to 8 years after refurbishment works, with low associated corrosion risk in areas protected by the hybrid anode systems. This is a positive finding for the wider implementation of hybrid anode systems as an alternative corrosion management technique. The reinforcement in the protected areas remained predominately in a passive condition, with calculated corrosion rates below the ISO 12696:2016 recommended threshold of 2mA/m2.

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Oh, Jin Seok, Myung Hyun Lee, J. D. Kim, and J. Y. Lee. "A New Control Algorithm for Impressed Current Cathodic Protection on the Underwater Hull." Materials Science Forum 449-452 (March 2004): 125–28. http://dx.doi.org/10.4028/www.scientific.net/msf.449-452.125.

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Cathodic protection is a system of preventing corrosion by forcing all surfaces of a hull to be cathode by providing external anodes. A metal can be made cathodic by electrically connecting it to a more anodic metal within the electrolyte. Anodes of these metals corrodepreferentially, the corrosion current of the anode achieving cathodic protection of the underwater hull to which they are connected. This paper presents a new current control algorithm for ICCP (Impressed Current Cathodic Protection) system. The anode of ICCP system is controlled by an external DC source with converter. The function of anode is to conduct the protective current into seawater. The DC source is generally obtained from main power system that contains a transformer, converter and etc. The proposed algorithm can operate AC-DC converter with current link. This algorithm includes the harmonic suppression control strategy and the optimum protection strategy and has tried to test the requirement current density for protection, the influence of voltage, the protection potential. Also, the properties of ICCP protected hull of ship in seawater are evaluated.

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Faisol, A., S. Sumarji, and G. Djatisukamto. "Pengaruh variasi pembagian jumlah anoda dengan pola horisontal terhadap laju korosi baja SS400 pada media air laut." Dinamika Teknik Mesin 8, no. 1 (January 1, 2018): 14. http://dx.doi.org/10.29303/dtm.v8i1.42.

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Sacrificial anode protection is one type of corrosion protection used to inhibit corrosion rate. The sacrificial anode protection works by utilizing the potential difference between anode and cathode. This research aims to determine the effect of variation in the distribution of quantities and distribution of sacrificial anode aluminum to SS400 steel corrosion rate. The method of calculating the corrosion rate used is the weight loss test. The results of this test indicate that the more uniform distribution of the anode on the surface of the cathode the better the resulting protection will be. The best protection is produced by 4 pieces of sacrificial anode size of 0,5 x 4 cm with an average rate of corrosion rate of 0,1067 mm/year. Protection with 2 pieces of sacrificial anode size 1 x 4 cm resulted in corrosion rate with average value 0,1462 mm/year, while on protection of 1 victim anode with size 2 x 4 cm can produce protection with average value of corrosion rate 0,1677 mm/year. Equivalent distribution of numbers and distributed anodes can narrow the distance between the anodes so that the value of the material's resitivity is smaller and the electrons can be distributed evenly over the entire cathode surface.The corrosion that occurs in SS400 steel is a kind of uniform corrosion. It is seen from the size of the cavity that occurs on each side of the specimen after the immersion process.

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Tian, Xuan, and Dong Yan Ding. "Fe-Based Sacrificial Anodes for Anti-Corrosion of 310S Stainless Steel." Materials Science Forum 852 (April 2016): 49–54. http://dx.doi.org/10.4028/www.scientific.net/msf.852.49.

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Sacrificial anode protection of stainless steel is required in severe application environment. In this paper, two kinds of Fe-based sacrificial anodes (20CrMo and 20CrMn) were used to protect 310S stainless steel. Protective effects were evaluated through constant current test and self-discharge test. Scanning electron microscope (SEM) and Energy Dispersive Spectrometer (EDS) were used to analyze the surface morphology and element composition of 310S cathodes after the tests. Experimental result indicates that both Fe-based sacrificial anodes have a driving voltage over 500mV, which enables a longer life than those of the Al-based or Zn-based anodes. The 20CrMo sacrificial anode presented more stable working potential, better state of activation and more uniform corrosion behavior than 20CrMn sacrificial anode did. The 310S cathode protected by 20CrMo had smoother surface and less oxide formation on the substrate.

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He, Han Bing, Yuan Wang, Pei Yu Huang, and Xu Peng Niu. "The Effect of the Fe²⁺_B/Fe³⁺_B Ratio on Electric Conductivity and Corrosion Resistance of Anodes." Materials Science Forum 896 (March 2017): 72–77. http://dx.doi.org/10.4028/www.scientific.net/msf.896.72.

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The effect of the Fe2+B/Fe3+B ratio (the ratio of divalent and trivalent iron ion in B position of the inverse spinel structure) in cermets on the electric conductivity and corrosion resistance of anodes was investigated. The experimental results showed that both the electrical conductivity and corrosion resistance are proportional to the Fe2+B/Fe3+B ratio on the surface of anodes because FeAl2O4 and NiAl2O4 are produced on the surface of the anode and Fe3+ in the NiFe2O4 is corroded preferentially during electrolysis.

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Al-Sultani, Kadhim F., and Jenan Nasser Nabat. "Characterization of Al-Zn-Sn as Sacrificial Anodes to Protect Underground Oil Pipelines in Al-Hilla Regional." Advanced Materials Research 628 (December 2012): 135–43. http://dx.doi.org/10.4028/www.scientific.net/amr.628.135.

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Sacrificial anode cathodic protection is one of the most widely used methods in protecting buried oil pipe lines against the corrosion damages. In the present work, a series of Aluminum alloys have been prepared as sacrificial anodes candidates to be used in the protection of the oil pipelines that pass through the Al-Hilla region. These prepared alloys were microstructurally and electrochemically characterized to evaluate their performance as Al-sacrificial anodes for cathodic protection of oil pipes The relationships between the protection potential with time, sacrificial anode life, discharge currents, and capacity of sacrificial anodes were found, taking into consideration the distance between sacrificial anode and protected steel sample. According to the results obtained, the best selection of sacrificial anodes was (Al-4% Zn-0.5% Sn) alloy at 30cm in Al-Hilla region.

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Al-Sultani, Kadhim F., and Jnan Nasser Nabat. "Effects of Tin on Aluminum – Zinc Alloy as Sacrificial Anode to Protect Underground Oil Pipeline in Al-Mahawil Regional." Advanced Materials Research 468-471 (February 2012): 1585–94. http://dx.doi.org/10.4028/www.scientific.net/amr.468-471.1585.

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Abstract Sacrificial anode cathodic protection is one of the most widely used methods in protecting buried oil pipe lines against the corrosion damages. In the present work, a series of Aluminum alloys have been prepared as sacrificial anodes candidates to be used in the protection of the oil pipelines that pass through the Al-Mahawil region. These prepared alloys were microstructurally and electrochemically characterized to evaluate their performance as Al-sacrificial anodes for cathodic protection of oil pipes The relationships between the protection potential with time, sacrificial anode life, discharge currents, and capacity of sacrificial anodes were found, taking into consideration the distance between sacrificial anode and protected steel sample. According to the results obtained, the best selection of sacrificial anodes was Al-4% Zn-0.4% Sn) alloy at 30cm in Al-Mahawil region.

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Durmus, Yasin Emre, Christoph Roitzheim, Hermann Tempel, Florian Hausen, Yair Ein-Eli, Hans Kungl, and Rüdiger-A. Eichel. "Analysis on discharge behavior and performance of As- and B-doped silicon anodes in non-aqueous Si–air batteries under pulsed discharge operation." Journal of Applied Electrochemistry 50, no. 1 (December 2, 2019): 93–109. http://dx.doi.org/10.1007/s10800-019-01372-5.

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Abstract Very high theoretical specific energies and abundant resource availability have emerged interest in primary Si–air batteries during the last decade. When operated with highly doped Si anodes and EMIm(HF)2.3F ionic liquid electrolyte, specific energies up to 1660 Wh kgSi−1 can be realized. Owing to their high-discharge voltage, the most investigated anode materials are $$\langle 100\rangle$$⟨100⟩ oriented highly As-doped Si wafers. As there is substantial OCV corrosion for these anodes, the most favorable mode of operation is continuous discharge. The objective of the present work is, therefore, to investigate the discharge behavior of cells with $$\langle 100\rangle$$⟨100⟩ As-doped Si anodes and to compare their performance to cells with $$\langle 100\rangle$$⟨100⟩ B-doped Si anodes under pulsed discharge conditions with current densities of 0.1 and 0.3 mA cm−2. Nine cells for both anode materials were operated for 200 h each, whereby current pulse time related to total operating time ranging from zero (OCV) to one (continuous discharge), are considered. The corrosion and discharge behavior of the cells were analyzed and anode surface morphologies after discharge were characterized. The performance is evaluated in terms of specific energy, specific capacity, and anode mass conversion efficiency. While for high-current pulse time fractions, the specific energies are higher for cells with As-doped Si anodes, along with low-current pulse fractions the cells with B-doped Si anodes are more favorable. It is demonstrated, that calculations for the specific energy under pulsed discharge conditions based on only two measurements—the OCV and the continuous discharge—match very well with the experimental data. Graphic abstract

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Puridetvorakul, Chanika, Nuchthana Poolthong, and Napachat Tareelap. "Corrosion Behavior of Al-Zn-In Sacrificial Anode Alloys Produced by Conventional Casting and Semi-Solid Metal Casting Processes." Key Engineering Materials 751 (August 2017): 101–6. http://dx.doi.org/10.4028/www.scientific.net/kem.751.101.

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A challenge in producing a sacrificial anode through conventional casting method is that the alloying elements in casting segregate during solidification, which further causes non-uniform anode corrosion reducing anode performance. In this paper, we investigated the performance of Al-5Zn-0.02In anode produced by conventional casting compared with by semi-solid casting technique. The performance of produced anodes were measured in terms of anode potential, current capacity, consumption rate and anode efficiency in 3.5% NaCl solution for 14 days. We found that the microstructure of the conventional cast anode had dendrites and coarse grains and the corrosion caused pitting corrosion. In contrast, the semi-solid cast anode had fine grains without any dendrites. The corrosion attacked mainly the grain boundaries and less on the matrix. Surprisingly, the conventional cast anode has about 10% higher efficiency than that of semi-solid cast anode.

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Bui, Xuan Ba, and Du Hong Nguyen. "STUDY ON CREATING PROTECTOR Zn BY SEMI-LIQUID PRESSURE METHOD." Science and Technology Development Journal 14, no. 1 (March 30, 2011): 85–96. http://dx.doi.org/10.32508/stdj.v14i1.1888.

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Results of Zn based anode production by semi-liquid pressure method have been presented. Microstructure, electrochemical characteristics and protective effectiveness of the newly developed anodes have been demonstrated in relation with products manufactured by traditional method. The newly developed samples had a potential of -1.1462 V and corrosion rate of 0.27 mpy in comparison of -1.223 V and 0.4894 mpy for traditionally prepared anodes.

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Cao, Mei, Zhong Cheng Guo, Xiang Lan Xie, and Su Qiong He. "Study on Structure and Properties of Ti/Pb-PANI-WC Inert Anodes." Advanced Materials Research 487 (March 2012): 53–57. http://dx.doi.org/10.4028/www.scientific.net/amr.487.53.

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Pb-PANI-WC inert anodes were prepared by direct current and pulse electrodeposition of PANI (conductive polyaniline) and WC particles with Pb2+ on the surface of titanium (Ti) substrate. The anodic polarization curves, cyclic voltammetry curves and Tafel polarization curves were measured in the solution of 50 g/L Zn2+, 150 g/L H2SO4 and 35°C, and the kinetic parameters of oxygen evolution, voltammetry charge, corrosion potential and corrosion current density have been obtained. The surface morphologies of the coating were investigated by using scanning electron microscope(SEM).The results show that the inert anodes prepared by pulse electrodeposition possess lower overpotential of oxygen evolution, higher electrocatalytic activity, and better reversibility of electrode reaction and corrosion resistance.

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Guan, Pingping, Aimin Liu, Zhongning Shi, Xianwei Hu, and Zhaowen Wang. "Corrosion Behavior of Fe-Ni-Al Alloy Inert Anode in Cryolite Melts." Metals 9, no. 4 (April 1, 2019): 399. http://dx.doi.org/10.3390/met9040399.

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Fe-Ni-based alloys are promising materials of inert anodes for use in aluminum electrolysis and adding Al can further improve the corrosion resistance. Fe-Ni-Al alloys with 1.4–8.6 wt.% Al were prepared by vacuum melting, and their corrosion as anodes during the production of pure Al (98.14–99.68%) by electrolysis was studied in a melt of NaF-AlF3-NaCl-CaF2-Al2O3 at 850 °C. The corrosion layer on the anode contains fluorine salt that corrodes the oxide film, and the inner layer is Ni-enriched while the outer layer is enriched with Fe and O due to the preferential oxidation of Fe. The electrolytically deposited oxide films on Fe-Ni-Al alloys with different compositions contains Fe2O3, Fe3O4, NiO, Al2O3, FeAl2O4, NiFe2O4, and other protective oxides, making the alloys very corrosion-resistant. The linear voltammetric curves can be divided into three parts: active dissolution, passivation transition, and over-passivation zones. The alloy with 3.9 wt.% Al (57.9Fe-38.2Ni-3.9Al) has a relatively negative passivation potential, and therefore, is easier to become passivated. According to the Tafel curve, this alloy shows a relatively positive corrosion potential as anode (1.20 V vs. Al/AlF3), and thus can form a protective film.

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Ralston, K. D., G. Williams, and N. Birbilis. "Effect of pH on the Grain Size Dependence of Magnesium Corrosion." Corrosion 68, no. 6 (June 1, 2012): 507–17. http://dx.doi.org/10.5006/i0010-9312-68-6-507.

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Prior works show that grain size can play a role in the corrosion of a metal; however, such works are nominally executed in a single electrolyte/environment at a single pH. In this work, the anodic and cathodic reaction kinetics of pure Mg specimens with grain sizes ranging from approximately 8 μm to 590 μm were compared as a function of pH in 0.1 mol dm−3 sodium chloride (NaCl) electrolytes using anodic polarization experiments and an in situ scanning vibrating electrode technique (SVET). Anodic polarization experiments showed that grain size is important in determining overall electrochemical response, but the environment dictates the form of the grain size vs. corrosion rate relationship (i.e., pH is the overall controlling factor). Consequently, the role of grain size upon corrosion cannot be fully assessed unless a variation in environment is simultaneously studied. For example, the anodic reaction, which dictates active corrosion, also dictates passivation, so the corrosion rate vs. grain size relationship has been shown to “flip” depending on pH. Further, SVET analysis of unpolarized Mg immersed in 0.1 mol dm−3 NaCl electrolyte at neutral pH showed that breakdown of passivity of cast Mg occurred after ~1 h immersion, giving filiform-like corrosion tracks. The front edges of these corrosion features were revealed as intense local anodes, while the remainder of the dark-corroded Mg surface, left behind as the anodes traversed the surface, became cathodically activated. In contrast, grain-refined Mg samples were significantly less susceptible to localized corrosion, and breakdown was not observed for immersion periods of up to 24 h.

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Lekatompessy, Sonja T. A. "ANALISIS PENGENDALIAN KOROSI PADA PERMUKAAN BASAH KAPAL-KAPAL BAJA DENGAN MENGGUNAKAN ZINK ANODA." ALE Proceeding 4 (August 17, 2021): 8–12. http://dx.doi.org/10.30598/ale.4.2021.8-12.

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Zink anodes are very importantfor reducing the corrosion rate on underwater surface area of hull plates. Zink anodes are affixed to parts of the vessel that are prone to seawater corrosion. This study aims to find out how much influence the installed current has on the corrosion rate by analyzing the data on the use of zink anodes in the field and the data on the use of zink anodes as a result of calculations so that the use of strong currents installed according to the need will reduce the rate of corrosion. To see the strong influence of current on the rate of corrosion, it takes data on the corrosion rate of the last 5 years from 9 vessels and also the number of zink anodes used each year. From the graph of the results of the calculation of strong current according to the theory and the results of the use of zinc anodes on nine vessels, the results obtained it is clear that the installed current strength must meet the needs of each vessel because it will affect the decrease in corrosion rate. On vessel No.3, an excess current strength of 0.539Amp to 1,386 Amp, a decrease in corrosion rate reaching 0.0317 mm/year in the 5th year. On vessel No. 4, an excess current strength of 0.444 Amp to 1.822 Amp there is a decrease in corrosion rate reaching 0.0138 mm/year in the 5th year. On vessel No. 9, an excess strong current of 4,894 Amp to 5,793 Amp there is a decrease in corrosion rate reaching 0.0371 mm/year in the 5th year.

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Sarhadi, Ali, Asger Bech Abrahamsen, and Mathias Stolpe. "Optimal Design of Galvanic Corrosion Protection Systems for Offshore Wind Turbine Support Structures." Corrosion 74, no. 7 (March 14, 2018): 829–41. http://dx.doi.org/10.5006/2688.

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The current work addresses a mass/cost-optimization procedure for galvanic anode cathodic protection systems based on both cathodic protection (CP) standards and numerical simulation. An approach is developed for optimizing the number and dimensions of the galvanic anodes, distributing the optimized anodes on the support structure, and finally evaluating the protective potential on the structure during the lifetime by using finite element (FE) software. An algorithm based on sequential quadratic programming is used for optimizing the number and dimensions of the anodes. Both simplified and detailed models are suggested for calculating the protective potential on the structure. The simplified model is selected based on its advantages in terms of calculation time and compatibility with DNV standard data. A time-dependent FE model is used to take into account the electrical isolation degradation of the structure coating as well as the mass reduction of the anodes during the CP lifetime. The performance of the proposed optimization process is examined on a mono bucket inspired (with some simplifications) by the Dogger Bank metrological mast in England. The optimized designs for different coating and anode types are compared and the best designs in terms of both cost and protective potential during the lifetime are suggested. The achieved results show that the proposed optimization procedure can reduce the cost of the CP system around 70% compared to the original non-optimized CP design of the Dogger Bank metrological mast. Furthermore, evaluating the time-evolution performance of the CP systems can reduce their lifetime uncertainty.

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Zhang, Min, Hong-Hua Ge, Xue-Juan Wang, Xin-Jing Meng, Yu-Zeng Zhao, and Qiang-Qiang Liao. "Research into the corrosion behavior of carbon steel in simulated reverse osmosis product water and seawater using a wire beam electrode." Anti-Corrosion Methods and Materials 62, no. 3 (May 5, 2015): 176–81. http://dx.doi.org/10.1108/acmm-01-2015-1496.

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Purpose – The purpose of this study was to explore the differences in the corrosion behavior of carbon steel in simulated reverse osmosis (RO) product water, and in seawater. Design/methodology/approach – The wire beam electrodes (WBE) and coupons made from Type Q235 carbon steel and were immersed in simulated reverse osmosis product water, and in seawater, for fifteen days. The corrosion potential distribution on the WBE at different times was measured. The corrosion rates of the carbon steel in different solutions were obtained using weight loss determinations. The different corrosion behavior of carbon steel in the two kinds of solution was analyzed. Findings – The results showed that the average corrosion potential, micro-cathode potential and micro-anode potential of the WBE decreased with time in simulated RO product water. During this period, the maximum potential difference between micro-cathodes and micro-anodes on the WBE surface also decreased with time. The potential difference was more than 260mV at the beginning of the test and was still greater than 110mV after fifteen days of immersion. The positions of cathodes and anodes remained basically unchanged and corrosion took place on the localized anode during the experiments. The average corrosion potential, micro-cathode potential and micro-anode potential on the WBE surface also decreased with time in the simulated seawater. However, the maximum potential difference between micro-cathode and micro-anode on the WBE surface in the simulated seawater was much smaller than was the case in simulated RO product water. It was 37.8 mV at the beginning of the test and was no more than 12mV after two days immersion. The positions of cathode region and anode kept changing, leading to overall uniform corrosion. The actual corrosion rate on the corroded anode region in simulated RO product water was greater than was the case in simulated seawater. Originality/value – The corrosion behavior differences of carbon steel between in RO product water and in seawater were revealed by using wire beam electrodes (WBE). From the micro point of view, it explained the reason why the actual corrosion rate of carbon steel in RO product water was greater than that in sea water. The results can be helpful to explore future corrosion control methods for carbon steel in RO product water.

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Wang, Yan Hua, and Yuan Yuan Liu. "Localized Corrosion of 304 Stainless Steel under a NaCl Droplet." Key Engineering Materials 480-481 (June 2011): 443–47. http://dx.doi.org/10.4028/www.scientific.net/kem.480-481.443.

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The distributions of corrosion potential and galvanic current of 304 stainless steel under a NaCl droplet were studied by using the wire beam electrode (WBE). It was found that the distributions of the electrochemical parameters were heterogeneous with isolated anodic and cathodic zones appeared randomly. During the corrosion process, the polarity of some anodes changed with the evolution of time. The localized corrosion rate and heterogeneity increased firstly, and then decreased afterward with the increase of time, which can be attributed to the cooperative effects of the aggressive ions and the corrosion products.

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28

Ma, L., K. Li, Y. Yan, and B. Hou. "Low Driving Voltage Aluminum Alloy Anode for Cathodic Protection of High Strength Steel." Advanced Materials Research 79-82 (August 2009): 1047–50. http://dx.doi.org/10.4028/www.scientific.net/amr.79-82.1047.

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The present work was focus on developing low driving voltage sacrificial anode for high strength steels. Taking the zinc and bismuth as main active elements, we designed and prepared several aluminum alloy anodes and investigated their electrochemical performance by galvanic test in natural seawater. The results showed that the anode exhibits high performance with 0.55wt.% Zn and 0.5wt.% Bi as the alloying elements. Its potential is varied from -800mV to -820mV, the current capacity is 2565 Ahr/kg, and the dissolution is homogeneous. We concluded that Al-0.55%Zn-0.5%Bi alloy anode can be used to high strength steel for corrosion protection. The microstructures of the anodes were observed by optical microscope, the result proposed that the uniform dissolution morphology of Al-0.55%Zn-0.5%Bi anode is due to its fine grain size.

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Van Nguyen, Chinh, Paul Lambert, Pal Mangat, Fin O’Flaherty, and Graeme Jones. "The Performance of Carbon Fibre Composites as ICCP Anodes for Reinforced Concrete Structures." ISRN Corrosion 2012 (December 20, 2012): 1–9. http://dx.doi.org/10.5402/2012/814923.

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Cathodic protection has been proven to be one of the most widely applicable and cost-effective solutions for tackling steel corrosion in reinforced concrete. In this study, the possible use of carbon fibre composites, which are primarily used to strengthen concrete members, has been investigated as impressed current cathodic protection anodes. Carbon fibre anodes have been assessed in both concrete and calcium hydroxide solution. Two bonding mediums incorporating epoxy and geopolymer have also been investigated. The results demonstrate that epoxy resin can be used for bonding carbon fibre fabric anodes to reinforced concrete structures while geopolymer is more effective for bonding carbon fibre reinforced polymer (CFRP) rod into preformed grooves in the concrete surface. The dissolution of carbon fibre anode appears to stablise after a period of time, dependent upon the size and shape of the anode and applied voltage and current. Based on the present results, a maximum current density of 128 mA/m2 of reinforcing steel area is recommended for the operation of CFRP fabric anode and 64 mA/m2 of reinforcing steel area for that of CFRP rod anode.

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Malekzadeh, M., N. Sivakugan, O. Kazum, and B. Mathan. "Effect of polyaniline-coated galvanized steel electrodes on electrokinetic sedimentation of dredged mud slurries." Canadian Geotechnical Journal 54, no. 8 (August 2017): 1150–57. http://dx.doi.org/10.1139/cgj-2016-0127.

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An experimental study on electrokinetic improvement of dredged marine sediments to accelerate their sedimentation for land reclamation purposes is presented. Electrokinetic stabilization is currently used to improve soils; however, its use on soils with marine sediments with low permeability is still questionable due to the deterioration of anodes caused by an electrolysis reaction. A number of traditional methods are employed in literature to reduce the corrosion degradation of metals, such as painting, galvanizing, and conversion coating. Conducting polymers, e.g., polyaniline, are of engineering interest due to their properties such as ease of preparation and their high environmental stability in protecting metals from corrosion. For this purpose, the anodes used in the electrokinetic testing cell herein were coated with polyaniline to investigate the effect on electrokinetic stabilization of the dredged mud. Two series of experiments were performed using a polyaniline-coated galvanized steel anode, and two series of experiments with noncoated galvanized steel anodes were also carried out as a control. Depending on the applied voltage, the settlement and electroosmotic permeability of the dredged mud varied during the process. Polyaniline coating increased the power consumption during the electrokinetic stabilization compared to the case where the same electric potential was applied using the uncoated electrodes. However, when 5 V electric potential was applied to the soil through the polyaniline coated anode, its settlement and electroosmotic permeability were equivalent to what was observed with the 30 V electric potential applied through the noncoated anode, with 3 times less energy consumption.

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Garcia, David, Stéphane Laurens, and Stéphane Panin. "Electrochemical behavior of zinc layer anodes used for galvanic protection of steel in reinforced concrete." RILEM Technical Letters 3 (December 20, 2018): 59–65. http://dx.doi.org/10.21809/rilemtechlett.2018.68.

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Steel corrosion is the most common reason for the premature deterioration of reinforced concrete structures. Consequently, cathodic protection of steel in concrete has been substantially developed during the past two decades. In particular, galvanic protection consists in generating a natural macrocell corrosion system in which a sacrificial metallic anode (zinc, typically) is involved to apply a cathodic polarization to the corroding steel layout, in order to mitigate or annihilate the corrosion kinetics. Whether the general principle of cathodic protection is not questionable, the global design process can be significantly improved by increasing the knowledge on electrochemical behaviours of the different components of the protecting system. Regarding zinc anodes in concrete, the literature is very scarce. The time evolution of such systems is also not rigorously addressed, aging effects are systematically ignored and zinc anodes are usually considered as non-polarizable and inert over time. In this paper, the polarization response of a zinc layer anode (ZLA) in concrete electrolyte and its time evolution are studied. The results show a rapid evolution of the ZLA behavior, once the protecting system is connected to steel reinforcements. Moreover, the characterization of ZLA provided relevant electrochemical properties for the numerical design of galvanic protection systems.

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32

Camurri, Carlos, Claudia Carrasco, and Yazmín Maril. "Optimal Deformation Hardening in Lead Base Anodes for Copper Electrowinning for an Appropiate Working Life." Materials Science Forum 879 (November 2016): 284–88. http://dx.doi.org/10.4028/www.scientific.net/msf.879.284.

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The lead base anodes (Pb-0.07% Ca-1.3% Sn) of 6 mm thick have limited working life due to their loss of thickness and corrosion during the electrowinning process. If this loss of thickness is combined with a low yield stress of the anodes, these are much more likely to suffer premature deformations and distortions in cells. The aim of this study is to optimize the deformation hardening of the anodes, so as to achieve the best combination of yield stress and corrosion resistance to increase their working life. To achieve this the aged anodes were cold rolled to different area reductions from the standard 50% to 75%. To each one of these rolled anodes its yield stress was determined by plane compression tests, their grain sizes was measured by means of optical microscopy and their corrosion rate was determined by coulomb metric assays in a cell using an electrolyte concentration of sulfuric acid of 180 g/l and a oxidation current density of 300 A/m2.It was found that the maximum yield stress of the anodes increases from 58 MPa to 64 MPa when cold reduction goes up from 50% and reach 70% . Regarding the corrosion rate, the maximum and minimum values were 0.33 mm/ year and 0.30 mm / year, i.e., with no significant differences between the different rolled anodes. Based on the above results it is concluded that an increase in the working life of the anodes is obtained simply by giving them greater cold rolling deformation from the current 50% to 70% of area reduction.

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33

Pourgharibshahi, M., and M. Meratian. "Corrosion morphology of aluminium sacrificial anodes." Materials and Corrosion 65, no. 12 (July 17, 2013): 1188–93. http://dx.doi.org/10.1002/maco.201307173.

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Ozyildirim, H. Celik, and Stephen R. Sharp. "Bridge Substructure Repairs with Self-Consolidating Concrete and Galvanic Anodes." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 27 (June 11, 2018): 56–64. http://dx.doi.org/10.1177/0361198118777353.

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Historically, the Virginia Department of Transportation (VDOT) has repaired chloride-contaminated reinforced concrete bridge substructure elements that contain vertical and overhead sections with either shotcrete or a conventional A3 (3,000 psi) or A4 (4,000 psi) concrete. This study investigated using self-consolidating concrete (SCC), which has a high flow rate, bonds well, has low permeability, and provides smooth surfaces, as another option. The study also explored the use of galvanic anodes to control corrosion activity in SCC repairs. In VDOT’s Lynchburg and Staunton Districts, SCC repairs were made with and without the use of galvanic anodes. This provided a means for determining the benefit of using the anodes. The needed repair areas were determined by visual observation and sounding. After 7 years of service, SCC repair areas with and without anodes did not exhibit corrosion activity; small vertical cracks were evident in the SCC but did not affect performance. The anodes can provide protection to the steel immediately adjacent to the repair areas. However, unrepaired concrete areas away from the patched area with anodes now require additional repairs. SCC can be successfully placed; however, attention should be paid to form pressure and slump loss. Selection of repair areas should be based on corrosion-related measurements such as half-cell or chloride content, rather than sounding. Progression of corrosion demonstrates the necessity of removing all chloride-contaminated concrete not just adjacent to, but also away from the reinforcement, as anodes in the repair area will provide protection only in a narrow area around the patch.

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Moon, Kyung Man, Myeong Hoon Lee, and Tae Sil Baek. "A Study on Galvanic Current Variation of Zn Sacrificial Anode Made by Including of Additive in Solutions with Various Conductivities." Materials Science Forum 926 (July 2018): 25–30. http://dx.doi.org/10.4028/www.scientific.net/msf.926.25.

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There have been two cathodic protection methods to inhibit corrosion of the structural steel piles which are being immerged under seawater, or to control corrosion of a hull part of the ship exposed to sea water. One of them is a sacrificial anode cathodic protection method that the steel pile can be protected with galvanic current by potential difference between sacrificial anode and corrosive structural steel. And, the sacrificial anode cathodic protection method have generally merits compared to impressed current method because it can be easily applied to everywhere which is not connected with electricity. However, when the steel piles are being submerged in low conductivity solution mixed with fresh water and sea water, the structural steel piles mentioned above have not been protected occasionally perfectively due to decreasing of galvanic current of zinc anode caused by deposited with oxide film on the surface of anode. In this study, four types of zinc anodes samples which are included with three types of additives such as NaCl, KCl, and ZnCl2were prepared, and galvanic currents, the polarization characteristics of these anodes was investigated using electrochemical methods such as polarization curves, impedance, cyclic voltammogtam and galvanic current in order to evaluate the effect of additive affecting to quality of zinc anode. The sample added with NaCl indicated the highest value of galvanic current density compared to other samples in the case of lower and higher conductivity solutions such as 0.32 and 2.97mS respectively, and the sample added with KCl revealed the smallest galvanic current density in middle value of conductivities such as 1.53 and 2.27 mS. Moreover, Zn sample no added with additive exhibited the smallest value of galvanic current density in the lowest conductivities such as 0.32 and 0.98 mS. Therefore, it is considered that the galvanic current of the sacrificial anode can be increased by adding of additive when the anode is submerged in low conductivity solution mixed with fresh water and sea water.

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36

Huang, Jian, Yuan Fa Ding, Xiang Dong Su, Yong Li, Yong Sheng Xiong, Dang Sheng Long, and Ze Hong Wu. "Industrial Application of Pb–Ag–Ca Anode with Surface Passivation for Zinc Electrowinning." Advanced Materials Research 941-944 (June 2014): 1398–401. http://dx.doi.org/10.4028/www.scientific.net/amr.941-944.1398.

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The Pb–Ag–Ca alloy anode with surface passivation was applied in industrial production of zinc electrowinning. The application situation was investigated by detection and tracking more than 3 months. The results were analyzed by comparison with the data acquired from the production using the reference anodes without surface treatment. The results showed that using the anode with surface passivation can increase zinc yield, reduce Pb content in zinc product, prolong the anode life by improving the corrosion resistance, and then reduce the production costs.

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37

Ramachandra Murthy, D. S., P. Gandhi, and G. Raghava. "Fatigue Life of Cathodically Protected Tubular Joints of Offshore Structures." Journal of Offshore Mechanics and Arctic Engineering 120, no. 4 (November 1, 1998): 232–36. http://dx.doi.org/10.1115/1.2829545.

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Steel jacket platforms are widely used for production and processing of oil from offshore fields. Tubular joints of these structures are susceptible to fatigue or corrosion fatigue cracking due to cyclic wave action, stress concentration, and corrosive environment. The submerged part of the structure is cathodically protected against corrosion by fixing sacrificial anodes at various places. The effect of cathodic protection on the fatigue life of tubular joints was studied by conducting fatigue tests on 13 T and Y-joints in air, under free corrosion, and with cathodic protection. The results of the studies are discussed in this paper.

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38

Vashi, R. T., and Diksha Naik. "Hexamine as Corrosion Inhibitors forZinc in Phosphoric Acid." E-Journal of Chemistry 7, s1 (2010): S1—S6. http://dx.doi.org/10.1155/2010/402764.

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The corrosion of zinc in phosphoric acid containing hexamine has been studied at different acid concentrations, inhibitor concentration and temperatures. Corrosion increases with the concentration of acid and the temperature. The inhibition efficiency (IE) of hexamine increases with the concentration of inhibitor. The IE decreases with the increase in concentration of acid. As temperature increases, percentage of inhibition decreases. The plot of log (Θ/1-Θ)versuslog C results in a straight line suggest that the inhibitors cover both the anodic and cathodic regions through general adsorption following Longmuir isotherm. Galvenostatic polarization curves show polarization of both anodes as well as cathodes.

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Pritzl, Matthew D., Habib Tabatabai, and Al Ghorbanpoor. "Laboratory Assessment of Select Methods of Corrosion Control and Repair in Reinforced Concrete Bridges." International Journal of Corrosion 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/175094.

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Fourteen reinforced concrete laboratory test specimens were used to evaluate a number of corrosion control (CoC) procedures to prolong the life of patch repairs in corrosion-damaged reinforced concrete. These specimens included layered mixed-in chlorides to represent chloride contamination due to deicing salts. All specimens were exposed to accelerated corrosion testing for three months, subjected to patch repairs with various treatments, and further subjected to additional three months of exposure to accelerated corrosion. The use of thermal sprayed zinc, galvanic embedded anodes, epoxy/polyurethane coating, acrylic coating, and an epoxy patch repair material was evaluated individually or in combination. The specimens were assessed with respect to corrosion currents (estimated mass loss), chloride ingress, surface rust staining, and corrosion of the reinforcing steel observed after dissection. Results indicated that when used in patch repair applications, the embedded galvanic anode with top surface coating, galvanic thermal sprayed zinc, and galvanic thermal sprayed zinc with surface coating were more effective in controlling corrosion than the other treatments tested.

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Wang, Chong Bi, Xiao Dong Kong, and Zhi Qiang Tian. "Evaluation of the Protection Effect on Copper with Different Sacrificial Anodes." Advanced Materials Research 602-604 (December 2012): 579–83. http://dx.doi.org/10.4028/www.scientific.net/amr.602-604.579.

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Sacrificial anodes performance of three iron alloys was measured by constant current test, The protection effects of iron alloys, zinc alloy and aluminum alloy sacrificial anodes on copper tube were compared and analysed by polarization test. The results show that all three iron alloys appearing well sacrificial anodes performance, with steady working potential, high practical electric capacity and current efficiency, the corrosion is uniform and the corrosion products fall easily. Iron alloys are more suitable for application on the cathodic protection of copper tube due to their more suitable driving voltage and coulpling current compared with zinc alloy and aluminum alloy.

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Wang, Hansen, Yayuan Liu, Yuzhang Li, and Yi Cui. "Lithium Metal Anode Materials Design: Interphase and Host." Electrochemical Energy Reviews 2, no. 4 (October 12, 2019): 509–17. http://dx.doi.org/10.1007/s41918-019-00054-2.

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Abstract Li metal is the ultimate anode choice due to its highest theoretical capacity and lowest electrode potential, but it is far from practical applications with its poor cycle lifetime. Recent research progresses show that materials designs of interphase and host structures for Li metal are two effective ways addressing the key issues of Li metal anodes. Despite the exciting improvement on Li metal cycling capability, problems still exist with these methodologies, such as the deficient long-time cycling stability of interphase materials and the accelerated Li corrosion for high surface area three-dimensional composite Li anodes. As a result, Coulombic efficiency of Li metal is still not sufficient for full-cell cycling. In the near future, an interphase protected three-dimensional composite Li metal anode, combined with high performance novel electrolytes might be the ultimate solution. Besides, nanoscale characterization technologies are also vital for guiding future Li metal anode designs. Graphic Abstract

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42

Zhang, Xiaotan, Jiangxu Li, Dongyan Liu, Mengke Liu, Tiansheng Zhou, Kaiwen Qi, Lei Shi, Yongchun Zhu, and Yitai Qian. "Ultra-long-life and highly reversible Zn metal anodes enabled by a desolvation and deanionization interface layer." Energy & Environmental Science 14, no. 5 (2021): 3120–29. http://dx.doi.org/10.1039/d0ee03898a.

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A bifunctional CNG membrane was constructed to achieve dendrite-free and corrosion-free Zn anodes by desolvation and deanionization effects. CNG/Zn anodes could have an ultra-long lifespan of ∼5500 h and a high CE (99.4%).

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43

Cao, Xiao Zhou, Zhu Xian Qiu, Zhong Ning Shi, Xian Wei Hu, Yun Gang Ban, and Zhao Wen Wang. "Anti-Oxidation and Anti-Corrosion Properties of Al-Si Metal Anodes." Materials Science Forum 546-549 (May 2007): 1149–52. http://dx.doi.org/10.4028/www.scientific.net/msf.546-549.1149.

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Al-Si metal anode was fabricated by cold-press sintering with Al and Si as embedded powder in argon atmosphere. The anti-oxidation in the air and anti-corrosion in molten cryolite properties of Al-Si metal anode at high temperature were examined. The experimental results showed that the oxidation kinetics curve obeyed the parabolic law. The corrosion behavior Al-Si metal anode was studied in electrolysis test. The electrolyte consisted of Na3AlF6(90 wt%),CaF2(5 wt%) and Al2O3(5 wt%) which corresponded to molecular ratio of 2.4. The results indicated that the cell voltage was stable and the electric polarized corrosion rate was higher than the static corrosion rate of metal anode. SEM photographs showed an oxidation film formed in the surface of Al-Si metal anode which can obstruct the further corrosion in molten cryolite. It may be concluded that Al-Si metal anode has good combination property and can replace the carbon anode in the aluminum cell.

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44

Jeong, Jin A., and Chung Kuk Jin. "The Experimental Measurement on the Throwing Power of Sacrificial Anode Cathodic Protection for Concrete Piles in Natural Sea Water." Advanced Materials Research 1125 (October 2015): 350–54. http://dx.doi.org/10.4028/www.scientific.net/amr.1125.350.

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This paper represents the experimental studies on the throwing power of sacrificial anode cathodic protection system applied to reinforced concrete piles in salt water condition by means of zinc anodes. Many previous studies show the effectiveness of sacrificial anode cathodic protection system, however, the major problem of sacrificial anode cathodic protection system is limited a distance to the point reaching protection current from the anode in high resistivity environments such as concrete, etc. In case of concrete pile in sea water condition, it should be combined submerged zone, tidal zone, splash zone, and atmospheric zone. In this study, the cathodic protection current by zinc sacrificial anodes was limited to scores of centimeters above the water line with tidal, depending on the concrete resistivity. Experimental tests were carried out on pile type reinforced concrete specimens with the change of water level. The test factors were corrosion and protection potential, current, and 4 hour depolarization potential. As a result of tests, cathodic protection current by zinc sacrificial anode was influenced up to about 10cm above the water line, and high resistivity areas such as atmospheric zone could not be protected with this system.

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45

Murthy, Yogesh Iyer, Sumit Gandhi, and Abhishek Kumar. "Comparative Study of Pure Mg and AZ91D as Sacrificial Anodes for Reinforced Cement Concrete Structures in Chloride Atmosphere." Civil Engineering Journal 4, no. 8 (August 26, 2018): 1750. http://dx.doi.org/10.28991/cej-03091110.

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Comparative study of the corrosion behavior of pure Magnesium and AZ91D anodes in reinforced cement concrete was undertaken in the present work. The steel reinforcements were kept in contact with these anodes electrochemically in chloride atmosphere and the half-cell potential drop was observed. Bare steel reinforcements were tied to the anodes and were also kept in high chloride atmosphere to test the mechanical properties. The yield stress and ultimate tensile stress were found to decrease by approximately 50MPa while the reduction in percentage elongation is approximately 25% for reinforcements tied to AZ91D and pure Mg at the end of 80 days compared to fresh steel reinforcement. The rate of corrosion of pure Mg was reportedly slightly higher compared to AZ91D due to the presence of inter-metallics as inferred through micro-graphs.

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Hopkins, Brandon J., and Debra R. Rolison. "Quantifying an acceptable open-circuit corrosion current for aluminum–air batteries." Materials Advances 2, no. 5 (2021): 1595–99. http://dx.doi.org/10.1039/d0ma01002b.

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47

Mirza, A. "Corrosion of lead anodes in base metals electrowinning." Journal of the Southern African Institute of Mining and Metallurgy 116, no. 6 (2016): 533–38. http://dx.doi.org/10.17159/2411-9717/2016/v116n6a7.

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Mohammadi, Farzad, Matthew Tunnicliffe, and Akram Alfantazi. "Corrosion Assessment of Lead Anodes in Nickel Electrowinning." Journal of The Electrochemical Society 158, no. 12 (2011): C450. http://dx.doi.org/10.1149/2.063112jes.

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Dolli, Hirudayasamy, Andiappan Kavitha, and Jeevarose . "Evaluation of Cathodic Protection Criteria for Embedded Steel Reinforcement in concrete structures." International Journal of Engineering & Technology 7, no. 3.12 (July 20, 2018): 333. http://dx.doi.org/10.14419/ijet.v7i3.12.16099.

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This paper presents the results of performance of sacrificial protection in preventing the rebar corrosion in chloride contaminated and chloride free concrete. In this present study, the effectiveness of sacrificial protection of embedded steel rebars has been evaluated on chloride contaminated and chloride free concrete slabs using ribbon type Zinc anodes with ion conductive polymer backfill over a period of 250 days of exposure. The results showed that the ribbon type zinc sacrificial anodes with the navel electrochemical interface (Ion conductive polymer backfill) can confer effective corrosion protection of embedded steel in concrete on preventing corrosion initiation in chloride contaminated as well as chloride free concretes slabs. The cathodic protection criteria evaluated on concrete unit slab showed that 100-150mV is necessary in the atmospheric exposure and 160-200mV under alternate wetting & drying conditions.

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Panic, Vladimir, Aleksandar Dekanski, Vesna Miskovic-Stankovic, Slobodan Milonjic, and Branislav Nikolic. "The role of the concentration profile of titanium oxide on the electrochemical behavior of RuO2-TiO2 coatings obtained by the sol-gel procedure." Journal of the Serbian Chemical Society 68, no. 12 (2003): 979–88. http://dx.doi.org/10.2298/jsc0312979p.

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Abstract:

In order to understand the role of TiO2 in the deactivation mechanism of an active RuO2?TiO2 coating, an additional TiO2 layer was introduced in the support coating interphase of regular Ti//[RuO2?TiO2 anode in one case and on the surface of the coating in the other. The electrochemical behavior of these, with TiO2 enriched, anodes was compared with the behavior of anodes with regular RuO2?TiO2 coatings, which were subjected to an accelerated stability test. A high-frequency semicircle in the complex plane plot obtained by electrochemical impedance spectroscopy, for a regular RuO2?TiO2 coating corresponds to TiO2 enrichment in the coating as a consequence of anode corrosion. In the case of the coatings with additional TiO2 layers, a high-frequency semicircle was not observed. The additional TiO2 layers increase the coating overall resistance and influence the coating impedance behavior at low frequencies. Similar equivalent electrical circuits were used to analyze the impedance behavior of coatings having an additional TiO2 layer at different position within RuO2?TiO2 coating.

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Journal articles on the topic 'Anodes – Corrosion'

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