The Experts below are selected from a list of 13506 Experts worldwide ranked by ideXlab platform
Ji Hyun Kim - One of the best experts on this subject based on the ideXlab platform.
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enhancement of Corrosion Resistance in carbon steels using nickel phosphorous titanium dioxide nanocomposite coatings under high temperature flowing water
Journal of Alloys and Compounds, 2017Co-Authors: Seunghyun Kim, Jeong Won Kim, Ji Hyun KimAbstract:Abstract To mitigate the Corrosion of carbon steels in high-temperature flowing water, we deposited Ni-P/TiO 2 nanocomposite coatings, composed of a Ni-P alloy matrix with dispersed TiO 2 nanoparticles. Their morphology, early-stage open-circuit voltage, weight loss, and microstructure evolution after the tests, performed in a temperature range of 125 °C–175 °C with 5 m/s flow, were investigated. The incorporation of TiO 2 nanoparticles in electroless Ni-P matrix was found to change the microstructure and Improve the Corrosion Resistance especially at 150 °C. At 150 °C, the Ni-P alloy undergoes severe Corrosion with the detachment of NiO while the Ni-P/TiO 2 nanocomposite coatings remain passive by the galvanic coupling of the Ni-P matrix and the nanoparticles. Based on this study, TiO 2 nanoparticles are found to enhance the passivation of the Ni-P alloy and, consequently, Improve Corrosion Resistance in high-temperature flowing water.
Kwan Ha Shin - One of the best experts on this subject based on the ideXlab platform.
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use of a poly ether imide coating to Improve Corrosion Resistance and biocompatibility of magnesium mg implant for orthopedic applications
Journal of Biomedical Materials Research Part A, 2013Co-Authors: Sang Bok Kim, Sung Mi Lee, Hyounee Kim, Kwan Ha Shin, Young Hag KohAbstract:This study investigated the utility of poly(ether imide) (PEI) coating for improving the Corrosion Resistance and biocompatibility of magnesium (Mg) implants for orthopedic application. In particular, the microstructure of the PEI coating layers was controlled by the adjustment of the temperature used to dry the spin-coated wet PEI films. When a wet PEI film was dried at 4°C, a relatively thick and porous coating layer was achieved as a result of an extensive exchange of the solvent with water in a moist environment. In contrast, when a wet PEI film was dried at 70°C, a relatively thin and dense layer was created due to the faster evaporation of the solvent with a negligible exchange of the solvent with water. The porous PEI coating layer showed higher stability than did the dense one when immersed in a simulated body fluid (SBF), which was presumably attributed to the formation of chemical bonding between the PEI and the Mg substrate. Both the porous and the dense PEI coated Mg specimens showed significantly Improved in vitro biocompatibility, which were assessed in terms of cell attachment, proliferation and differentiation. However, interestingly, the dense PEI coating layer showed greater cell proliferation and differentiation than did the porous layer. .
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use of a poly ether imide coating to Improve Corrosion Resistance and biocompatibility of magnesium mg implant for orthopedic applications
Journal of Biomedical Materials Research Part A, 2013Co-Authors: Ji Hoon Jo, Kwan Ha ShinAbstract:This study investigated the utility of poly(ether imide) (PEI) coating for improving the Corrosion Resistance and biocompatibility of magnesium (Mg) implants for orthopedic application. In particular, the microstructure of the PEI coating layers was controlled by the adjustment of the temperature used to dry the spin-coated wet PEI films. When a wet PEI film was dried at 4°C, a relatively thick and porous coating layer was achieved as a result of an extensive exchange of the solvent with water in a moist environment. In contrast, when a wet PEI film was dried at 70°C, a relatively thin and dense layer was created due to the faster evaporation of the solvent with a negligible exchange of the solvent with water. The porous PEI coating layer showed higher stability than did the dense one when immersed in a simulated body fluid (SBF), which was presumably attributed to the formation of chemical bonding between the PEI and the Mg substrate. Both the porous and the dense PEI coated Mg specimens showed significantly Improved in vitro biocompatibility, which were assessed in terms of cell attachment, proliferation and differentiation. However, interestingly, the dense PEI coating layer showed greater cell proliferation and differentiation than did the porous layer. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Seunghyun Kim - One of the best experts on this subject based on the ideXlab platform.
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enhancement of Corrosion Resistance in carbon steels using nickel phosphorous titanium dioxide nanocomposite coatings under high temperature flowing water
Journal of Alloys and Compounds, 2017Co-Authors: Seunghyun Kim, Jeong Won Kim, Ji Hyun KimAbstract:Abstract To mitigate the Corrosion of carbon steels in high-temperature flowing water, we deposited Ni-P/TiO 2 nanocomposite coatings, composed of a Ni-P alloy matrix with dispersed TiO 2 nanoparticles. Their morphology, early-stage open-circuit voltage, weight loss, and microstructure evolution after the tests, performed in a temperature range of 125 °C–175 °C with 5 m/s flow, were investigated. The incorporation of TiO 2 nanoparticles in electroless Ni-P matrix was found to change the microstructure and Improve the Corrosion Resistance especially at 150 °C. At 150 °C, the Ni-P alloy undergoes severe Corrosion with the detachment of NiO while the Ni-P/TiO 2 nanocomposite coatings remain passive by the galvanic coupling of the Ni-P matrix and the nanoparticles. Based on this study, TiO 2 nanoparticles are found to enhance the passivation of the Ni-P alloy and, consequently, Improve Corrosion Resistance in high-temperature flowing water.
M Shamania - One of the best experts on this subject based on the ideXlab platform.
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the study of ni based nano crystalline and amorphous alloy coatings on aisi 304 stainless steel for pem fuel cell bipolar plate application
International Journal of Hydrogen Energy, 2017Co-Authors: Vahid Rajaei, Hamed Rashtchi, K Raeissi, M ShamaniaAbstract:Abstract Bipolar plates are one of the most important parts of proton exchange membrane fuel cells (PEMFCs) which their performance has appreciable effect on cell operation. In this study, Ni–Mo and Ni–Mo–P alloy coatings were electrodeposited on AISI 304 stainless steel specimens as metallic bipolar plates in order to Improve Corrosion Resistance, hydrophobicity and electrical conductivity of the specimens. Scanning electron microscopy (SEM) micrographs showed that the prepared coatings were uniform and compact. Moreover, X-ray diffraction (XRD) analysis indicated that the coatings were composed of a solid solution where Ni–Mo and Ni–Mo–P coatings had nanocrystalline and amorphous structures, respectively. The potentiodynamic and potentiostatic polarization tests in a simulated PEMFC cathode environment showed that Corrosion Resistance of the coated specimens was considerably Improved compared to that of the bare one. Furthermore, interfacial contact Resistance (ICR) before and after potentiostatic test was significantly decreased by applying Ni–Mo and Ni–Mo–P coatings, where ICR values of the as-deposited bipolar plates were reduced by approximately eight times in comparison to that of the bare 304 stainless steel at typical compaction force of 220 N/cm 2 . Therefore, the investigated Ni–Mo and Ni–Mo–P coatings would be potentially good candidates as metallic bipolar plates in PEMFC. Moreover, Ni–Mo and Ni–Mo–P alloy coatings showed higher surface hydrophobicity than the bare 304 stainless steel, which is advantageous for water management and also for Corrosion Resistance Improvement.
Mohammadhossein Fathi - One of the best experts on this subject based on the ideXlab platform.
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Effect of Surface Treatment and Metallic Coating on Corrosion Behavior and Biocompatibility of Surgical 316L Stainless Steel Implant
Journal of Materials Science & Technology, 2012Co-Authors: Ali Parsapour, Saied Nouri Khorasani, Mohammadhossein FathiAbstract:Surface engineering technology is a suitable method for coatings on the metal surfaces or performing surface modification treatment, which can Improve Corrosion Resistance and biocompatibility of metals. In this research, Corrosion behavior of Nb coating on H2SO4 and HNO3 treated AISI stainless steel 316L (SS) was evaluated. Nb coating was carried out using physical vapor deposition process on the SS. Characterization techniques including scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) technique were used to investigate the microstructure and morphology of the coated and treated SS. Electrochemical potentiodynamic tests were performed in two types of physiological solutions and compared with the pristine SS specimens. Cyclic polarization tests were performed to evaluate resistivity against pitting. Experimental results indicate that Nb coating and surface treatment of the SS had a positive effect on Improvement of Corrosion behavior. The decrease in Corrosion current densities was significant for coated and treated specimens. The Corrosion current density was much lower than the values obtained for pristine specimens.
