• Corrosion Science and Technology
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• v.15 no.4
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• pp.166-170
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• 2016

The combined process of porous type anodizing and desiccation treatment was applied to improve wettability of A1050 aluminum alloy. The water contact angles of anodized samples were increaseds considerably with desiccation treatment. However, there was no considerable effect of polishing and anodizing time on water contact angle. The corrosion behavior with the treatments was investigated electrochemically. The corrosion resistance of the samples in 3.5 mass% NaCl solutions increased with higher contact angle. Anodized and desiccated samples showed better corrosion resistance than un-desiccated samples around rest potential region.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.133-133
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• 2012

플라즈마 전해산화(Plasma Electrolytic Oxidation;PEO) 피막은 Anodizing 피막에 비해 화학 부식성, 플라즈마 부식성 등의 특성이 뛰어나지만 표면 거칠기는 Anodizing 피막이 우수한 것으로 알려져 있다. 본 연구에서는 PEO 피막의 제작시 사용된 Power Supply의 펄스 변조(PAM, PWM 방식)을 통하여 표면 거칠기를 제어하는 방법에 대한 실험을 수행하였다. 그리고 펄스 변조 전후의 시편의 내전압과 플라즈마 부식성 등의 특성을 비교하였다. 또한 펄스 변조 전후 PEO 시편과 Anodizing 시편의 표면 거칠기, 내전압, 플라즈마 부식성 등의 특성을 비교하였다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.207-211
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• 2002

Anodizing film was prepared by anodic oxidation of pure aluminum(purity > 99.50) using DC power supply for constant current mode in an electrolytic solution of surface of sulfuric acid. Effects of pre-treatment process such as chemical polishing, acid cleaning, alkali etching before anodic oxidation, were studied to microstructures and surface morphologies. A roughness on surface of anodizing film had to be decreased for amorphous phase by anodic oxidation. A roughness on surface of anodizing film decrease as annealing temperature increased in chemical polishing.

• Journal of Powder Materials
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• v.21 no.2
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• pp.114-118
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• 2014

In this study, an aluminum oxide layer for sealing treatment of nano-diamond powder was synthesized by anodizing under constant current. The produced pore size and oxide thickness were investigated using scanning electron microscopy. The pore size increased as the treatment time increased, current density increased, sulfuric acid concentration decreased, which is different from the results under constant voltage, due to a dissolution of the oxide layers. The oxide layer thickness by the anodizing increased as temperature, time, and current density increased. The results of this study can be applied to optimize the sealing treatment process of nano-diamond particles of 4-10 nm to enhance the resistances of corrosion and wear of the matrix.

• Korean Journal of Materials Research
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• v.16 no.8
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• pp.503-510
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• 2006

The measurement of specific gases is based on the reversible conductivity change of sensing materials in semiconductor type gas sensors. For an application as gas sensors of high sensitivity, porous $SnO_2$ films have been fabricated by anodizing of pure Sn foil in oxalic acid and characteristics of anodic tin oxide films have been investigated. Pore diameter and distribution were dependent on process conditions such as electrolyte concentration, applied voltage, anodizing temperature, and time. Characteristics of anodic films were explained with current density-time curves.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.3
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• pp.355-362
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• 2011

In this paper, we developed the equipment to forming the insulation film which there are operated an electrolysis principles in particular solution. In the earlier, there are supplied the anode by unipolar voltage with pulse, in this paper, there are supplied the anode by bipolar voltage with pulse, alternately. And then, we examinate the system that there are developed the bipolar anodizing equipment using H-bridge. There are modulated pulse width for the variable current. In the results, we obtained the results of the uniform film surface that compared with the unipolar anodizing.

• Korean Journal of Materials Research
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• v.29 no.2
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• pp.65-72
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• 2019

Dual porous structures are observed for the first time on a metallic Cu surface underneath anodic Cu oxide by the application of an anodizing voltage to Cu in oxalic acid. The as-prepared porous Cu surface contains macropores of less than $1{\mu}m$ diameter and mesopores of about tens of nanometers diameter with circular shapes. The size and density (number of pores/area) of the macropores are dependent on the applied voltage. It is likely that the localized dissolution (corrosion) of Cu in oxalic acid under the anodizing voltages is responsible for the formation of the mesopores, and the combination of a number of the mesopores might create the macropores, especially under a relatively high anodizing voltages or a prolonged anodizing time. The variations of pore structure (especailly macropores) with applied voltage and time are reasonably explained on the basis of the proposed mechanism of pore formation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.151-152
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• 2012

• Journal of the Korean Electrochemical Society
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• v.4 no.2
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• pp.47-52
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• 2001

AAO template having nano scale pores of high aspect ratio has been prepared through anodizing of aluminum foil in sulfuric acid electrolyte. The effect of anodizing parameters on the pore size and distribution was also examined to obtain the proper AAO as a template material of nanowire. The surface of AAO template prepared was observed by SEM to examine the mean size and distribution of pores generated by the anodizing and Fe nanowires obtained by AC electroforming using AAO template were also observed with TEM to determine the length and shape of them. From the results of work, it was found that the mean size or distribution of pores was influenced significantly by the anodizing parameters such as voltage and temperature of electrolyte. Mean length and aspect ratio of Fe nanowires prepared in the work were found to be $10{\mu}m\;and\;300\;to\;1,000$, respectively.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.151-152
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• 2012