The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform
Salman A Alduheisat - One of the best experts on this subject based on the ideXlab platform.
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Cathodic Polarization behavior of the structural steel wires under different prestressing conditions
Journal of materials research and technology, 2017Co-Authors: Amjad Saleh Elamoush, Salman A AlduheisatAbstract:Abstract Cold-drawn structural steel wires prestressed to different levels and Cathodically polarized at various potentials were investigated using electrochemical techniques and slow strain rate tests. The potentiodynamic Polarization revealed that prestressing enhances the active anodic dissolution of the structural steel wires. The corrosion current density and corrosion potential were observed to vary with prestressing levels applied to the structural steel wire specimens. The structural steel wire prestressed to 80% of its original tensile strength and Cathodically polarized at −1500 mV exhibited the highest current densities and lowest corrosion potentials after potentiodynamic Polarization, which indicate that the above prestressing and Cathodic Polarization conditions lower the corrosion resistance of the material. Moreover, the tensile results show that the structural steel wire prestressed to higher levels and Cathodically polarized at lower potentials was more susceptible to degradation of the tensile properties. The structural steel wire prestressed to 80% level and Cathodically polarized at a potential of −1500 mV exhibits the lowest UTS and ductility. The tensile fracture surfaces of the steel wires prestressed and Cathodically polarized under above conditions exhibit mostly quasi-cleavage brittle fracture character. Furthermore, the brittle regions were observed to increase with increasing the prestressing levels and decreasing the Cathodic Polarization potentials applied to the structural steel wires.
Masahiro Seo - One of the best experts on this subject based on the ideXlab platform.
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The Cathodic Polarization of aluminum covered with anodic oxide films in a neutral borate solution—II. Film breakdown and pit formation
Corrosion Science, 1994Co-Authors: Hiroshi Takahashi, K. Fujiwara, Masahiro SeoAbstract:Abstract Porous and barrier type oxide films were formed anodically on pure aluminum and dissolved chemically. The specimens were then Cathodically polarized by the potential sweep method in a neutral borate solution. It was found that the Cathodic current starts to increase at about −2 to −3 V(Ag/AgCl) and that at more negative potentials increases almost linearly, accompanied by hydrogen evolution. The Cathodic Polarization curve shifts in the anodic direction with decreasing film formation potential and increasing chemical dissolution time. During Cathodic Polarization, cubic-shaped pits are formed by local corrosion of the metal substrate. The number of pits formed by Cathodic Polarization is larger for porous than for barrier type oxide films, while the pit number is independent of the film formation potential, it increases considerably with increasing chemical dissolution time. The ratio of the local corrosion rate to the electrochemical reaction rate during Cathodic Polarization is about 0.03 on specimens without chemical dissolution, and about 0.10 with chemical dissolution. The effect of film structure on the pit formation during Cathodic Polarization is discussed in terms of imperfections in the oxide.
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the Cathodic Polarization of aluminum covered with anodic oxide films in a neutral borate solution ii film breakdown and pit formation
Corrosion Science, 1994Co-Authors: Hiroshi Takahashi, K. Fujiwara, Masahiro SeoAbstract:Abstract Porous and barrier type oxide films were formed anodically on pure aluminum and dissolved chemically. The specimens were then Cathodically polarized by the potential sweep method in a neutral borate solution. It was found that the Cathodic current starts to increase at about −2 to −3 V(Ag/AgCl) and that at more negative potentials increases almost linearly, accompanied by hydrogen evolution. The Cathodic Polarization curve shifts in the anodic direction with decreasing film formation potential and increasing chemical dissolution time. During Cathodic Polarization, cubic-shaped pits are formed by local corrosion of the metal substrate. The number of pits formed by Cathodic Polarization is larger for porous than for barrier type oxide films, while the pit number is independent of the film formation potential, it increases considerably with increasing chemical dissolution time. The ratio of the local corrosion rate to the electrochemical reaction rate during Cathodic Polarization is about 0.03 on specimens without chemical dissolution, and about 0.10 with chemical dissolution. The effect of film structure on the pit formation during Cathodic Polarization is discussed in terms of imperfections in the oxide.
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The Cathodic Polarization of aluminum covered with anodic oxide films in a neutral borate solution—I. The mechanism of rectification
Corrosion Science, 1994Co-Authors: Hiroshi Takahashi, K. Fujiwara, K. Kasahara, Masahiro SeoAbstract:Abstract Aluminum covered with barrier type anodic oxide films was polarized anodically and Cathodically in a neutral borate solution in a vacuum to investigate rectification phenomena. Rectification took place only in the solution, suggesting that it is due to a high rate of proton reduction during Cathodic Polarization. Potentiostatic Cathodic Polarization in solution showed a threshold potential of −2.0 V(Ag/AgCl). At more positive potentials, a minute Cathodic current flows, while the current increases with time below −2 V(Ag/AgCl). The increase in current was accompanied by hydrogen evolution at weak spots in the oxide film, causing the formation of a small number of pits. The mechanism of pit formation is discussed in terms of alkalization at the bottom of pits.
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the Cathodic Polarization of aluminum covered with anodic oxide films in a neutral borate solution i the mechanism of rectification
Corrosion Science, 1994Co-Authors: Hiroshi Takahashi, K. Fujiwara, K. Kasahara, Masahiro SeoAbstract:Abstract Aluminum covered with barrier type anodic oxide films was polarized anodically and Cathodically in a neutral borate solution in a vacuum to investigate rectification phenomena. Rectification took place only in the solution, suggesting that it is due to a high rate of proton reduction during Cathodic Polarization. Potentiostatic Cathodic Polarization in solution showed a threshold potential of −2.0 V(Ag/AgCl). At more positive potentials, a minute Cathodic current flows, while the current increases with time below −2 V(Ag/AgCl). The increase in current was accompanied by hydrogen evolution at weak spots in the oxide film, causing the formation of a small number of pits. The mechanism of pit formation is discussed in terms of alkalization at the bottom of pits.
Amjad Saleh Elamoush - One of the best experts on this subject based on the ideXlab platform.
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Cathodic Polarization behavior of the structural steel wires under different prestressing conditions
Journal of materials research and technology, 2017Co-Authors: Amjad Saleh Elamoush, Salman A AlduheisatAbstract:Abstract Cold-drawn structural steel wires prestressed to different levels and Cathodically polarized at various potentials were investigated using electrochemical techniques and slow strain rate tests. The potentiodynamic Polarization revealed that prestressing enhances the active anodic dissolution of the structural steel wires. The corrosion current density and corrosion potential were observed to vary with prestressing levels applied to the structural steel wire specimens. The structural steel wire prestressed to 80% of its original tensile strength and Cathodically polarized at −1500 mV exhibited the highest current densities and lowest corrosion potentials after potentiodynamic Polarization, which indicate that the above prestressing and Cathodic Polarization conditions lower the corrosion resistance of the material. Moreover, the tensile results show that the structural steel wire prestressed to higher levels and Cathodically polarized at lower potentials was more susceptible to degradation of the tensile properties. The structural steel wire prestressed to 80% level and Cathodically polarized at a potential of −1500 mV exhibits the lowest UTS and ductility. The tensile fracture surfaces of the steel wires prestressed and Cathodically polarized under above conditions exhibit mostly quasi-cleavage brittle fracture character. Furthermore, the brittle regions were observed to increase with increasing the prestressing levels and decreasing the Cathodic Polarization potentials applied to the structural steel wires.
Hiroshi Takahashi - One of the best experts on this subject based on the ideXlab platform.
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The Cathodic Polarization of aluminum covered with anodic oxide films in a neutral borate solution—II. Film breakdown and pit formation
Corrosion Science, 1994Co-Authors: Hiroshi Takahashi, K. Fujiwara, Masahiro SeoAbstract:Abstract Porous and barrier type oxide films were formed anodically on pure aluminum and dissolved chemically. The specimens were then Cathodically polarized by the potential sweep method in a neutral borate solution. It was found that the Cathodic current starts to increase at about −2 to −3 V(Ag/AgCl) and that at more negative potentials increases almost linearly, accompanied by hydrogen evolution. The Cathodic Polarization curve shifts in the anodic direction with decreasing film formation potential and increasing chemical dissolution time. During Cathodic Polarization, cubic-shaped pits are formed by local corrosion of the metal substrate. The number of pits formed by Cathodic Polarization is larger for porous than for barrier type oxide films, while the pit number is independent of the film formation potential, it increases considerably with increasing chemical dissolution time. The ratio of the local corrosion rate to the electrochemical reaction rate during Cathodic Polarization is about 0.03 on specimens without chemical dissolution, and about 0.10 with chemical dissolution. The effect of film structure on the pit formation during Cathodic Polarization is discussed in terms of imperfections in the oxide.
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the Cathodic Polarization of aluminum covered with anodic oxide films in a neutral borate solution ii film breakdown and pit formation
Corrosion Science, 1994Co-Authors: Hiroshi Takahashi, K. Fujiwara, Masahiro SeoAbstract:Abstract Porous and barrier type oxide films were formed anodically on pure aluminum and dissolved chemically. The specimens were then Cathodically polarized by the potential sweep method in a neutral borate solution. It was found that the Cathodic current starts to increase at about −2 to −3 V(Ag/AgCl) and that at more negative potentials increases almost linearly, accompanied by hydrogen evolution. The Cathodic Polarization curve shifts in the anodic direction with decreasing film formation potential and increasing chemical dissolution time. During Cathodic Polarization, cubic-shaped pits are formed by local corrosion of the metal substrate. The number of pits formed by Cathodic Polarization is larger for porous than for barrier type oxide films, while the pit number is independent of the film formation potential, it increases considerably with increasing chemical dissolution time. The ratio of the local corrosion rate to the electrochemical reaction rate during Cathodic Polarization is about 0.03 on specimens without chemical dissolution, and about 0.10 with chemical dissolution. The effect of film structure on the pit formation during Cathodic Polarization is discussed in terms of imperfections in the oxide.
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The Cathodic Polarization of aluminum covered with anodic oxide films in a neutral borate solution—I. The mechanism of rectification
Corrosion Science, 1994Co-Authors: Hiroshi Takahashi, K. Fujiwara, K. Kasahara, Masahiro SeoAbstract:Abstract Aluminum covered with barrier type anodic oxide films was polarized anodically and Cathodically in a neutral borate solution in a vacuum to investigate rectification phenomena. Rectification took place only in the solution, suggesting that it is due to a high rate of proton reduction during Cathodic Polarization. Potentiostatic Cathodic Polarization in solution showed a threshold potential of −2.0 V(Ag/AgCl). At more positive potentials, a minute Cathodic current flows, while the current increases with time below −2 V(Ag/AgCl). The increase in current was accompanied by hydrogen evolution at weak spots in the oxide film, causing the formation of a small number of pits. The mechanism of pit formation is discussed in terms of alkalization at the bottom of pits.
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the Cathodic Polarization of aluminum covered with anodic oxide films in a neutral borate solution i the mechanism of rectification
Corrosion Science, 1994Co-Authors: Hiroshi Takahashi, K. Fujiwara, K. Kasahara, Masahiro SeoAbstract:Abstract Aluminum covered with barrier type anodic oxide films was polarized anodically and Cathodically in a neutral borate solution in a vacuum to investigate rectification phenomena. Rectification took place only in the solution, suggesting that it is due to a high rate of proton reduction during Cathodic Polarization. Potentiostatic Cathodic Polarization in solution showed a threshold potential of −2.0 V(Ag/AgCl). At more positive potentials, a minute Cathodic current flows, while the current increases with time below −2 V(Ag/AgCl). The increase in current was accompanied by hydrogen evolution at weak spots in the oxide film, causing the formation of a small number of pits. The mechanism of pit formation is discussed in terms of alkalization at the bottom of pits.
Luis A Godinez - One of the best experts on this subject based on the ideXlab platform.
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Cathodic Polarization effect on the electro-Fenton regeneration of activated carbon
Journal of Applied Electrochemistry, 2015Co-Authors: Jennifer A. Bañuelos, Orlando García-rodríguez, Francisco J. Rodríguez-valadez, Juan Manríquez, Erika Bustos, A Rodriguez, Luis A GodinezAbstract:The regeneration of dye-adsorbed activated carbon (AC) using an electro-Fenton approach was studied and compared with typical regeneration methodologies (thermal, solvent extraction, and Fenton). The Cathodic Polarization effect of the electro-Fenton process on the AC surface was compared based on the textural and structural properties surface via physicochemical characterization techniques. The total organic carbon decay and color removal of a dye-contaminated model solution were also studied using the different methodologies, and several regeneration cycles were employed for each methodology in order to assess the regeneration efficiency and correlate it with AC structural changes. The results show that the electrochemical process is the best method to regenerate AC because it maximizes the adsorption efficiency (approximately 80–90 %) compared to other methods of regeneration (
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Cathodic Polarization effect on the electro fenton regeneration of activated carbon
Journal of Applied Electrochemistry, 2015Co-Authors: Jennifer A. Bañuelos, Juan Manríquez, Erika Bustos, A Rodriguez, Orlando Garciarodriguez, Francisco J Rodriguezvaladez, Luis A GodinezAbstract:The regeneration of dye-adsorbed activated carbon (AC) using an electro-Fenton approach was studied and compared with typical regeneration methodologies (thermal, solvent extraction, and Fenton). The Cathodic Polarization effect of the electro-Fenton process on the AC surface was compared based on the textural and structural properties surface via physicochemical characterization techniques. The total organic carbon decay and color removal of a dye-contaminated model solution were also studied using the different methodologies, and several regeneration cycles were employed for each methodology in order to assess the regeneration efficiency and correlate it with AC structural changes. The results show that the electrochemical process is the best method to regenerate AC because it maximizes the adsorption efficiency (approximately 80–90 %) compared to other methods of regeneration (<20 %) after 10 working cycles. These results led us to conclude that Cathodic Polarization regenerates the AC more efficiently than conventional methods.