• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.3-4
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• 2014

• 한국전기화학회:학술대회논문집
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• 2001.10a
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• pp.3-5
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• 2001

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.362-362
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• 2006

Chromic acid anodizing of aluminium is an effective process for producing a substrate which provides excellent surface properties to assembly. However, new chromium-free finishing metal treatments are being developed to reach new environmental goals. Present study deals with chromium free experimental conditions for both deoxidizing and anodizing treatments. Results clearly demonstrate the potentiality for environmentally friendly treatments to get suitable metal-adhesive performance. In particular, the role of both metal surface porosity and chemical composition has been highlighted thus allowing to propose alternative to classical treatments for aeronautic applications.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1334-1338
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• 2005

A limit switch box is used for an indicator of a valve actuator. This device indicates an opening and closing of a valve or a throttle in the valve actuator. In a ship, equipments require safety and robustness because of a rough environment and a specific condition during a voyage. However, the limit switch box has been used in an indoor environment generally. This study developed a new limit switch box which can be used at an outdoor environment. This study designed the new limit switch box. The housing of the limit switch box was made by an aluminum die cast method with surface painting after anodizing or chromate coating. In order to evaluate the endurance of the housing, the endurance tests against salt water have been conducted. Experiment results showed that the proposed device provides a reliable performance against salt water.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.463-466
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• 2011

In this work, we investigate anodization of Pb in ethylene glycol containing small amount of $NH_4F$, demonstrating that ${\beta}-PbF_2$ particles with octahedral morphology can be prepared by adjusting the applied potential and anodizing time. FE-SEM images and XRD measurements of anodic nanostructures as a function of anodizing time clearly show that PbO is first formed on Pb. Subsequently, a local dissolution of PbO leads to formation of skeleton structure of PbO, releasing $Pb^{2+}$ ions in the electrolyte. The lead ions can be precipitated on the walls or intersection of the skeleton walls when the concentration of lead ions is saturated. The method described in this article shows the feasibility of formation of metal fluoride crystal by anodization of metal in a fluoride containing solution.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.5
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• pp.782-792
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• 2004

The effects of sealing solution for anodized Mg-Al alloys and their corrosion resistance property were investigated. focusing on the effects of anodizing potentials aluminum contents and sealing solutions. All of the anodized specimens showed better corrosion resistance than that of non-anodized specimens, regardless of applied potentials. It was found that the anodic film formed at 4 V had the best corrosion resistance. The sealing effects were improved by increasing the temperature of distilled water. the pH of solution and the relative intensity ratio of $Mg(OH)_2$.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.697-700
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• 2002

Porous anodic aluminum oxide(AAO) templates prepared by anodizing method were used for growing multiwalled carbon nanotubes(CNTs). AAO templates with the homogeneous pore diameter and length were obtained by two step anodizing technique. Using AAO templates, vertically well-ordered two-dimensional carbon nanotube arrays were fabricated. We investigated the field emission property of CNTs grown using different catalyst metals in vacuum chamber (<$10^{-7}$ Torr) on AAO Template. To explain the different emission property, the surface reaction between catalysts and alumina pores which inserted carbon species of $C_2H_2$ using High resolution transmission electron microscopy (HRTEM) was studied.

• Journal of ILASS-Korea
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• v.21 no.1
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• pp.58-63
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• 2016

This study presents the dynamic characteristics of an impinging droplet on hydrophobic and hydrophilic surfaces with various texture area fractions. The flat surface was fabricated by using the drilling technique to make micro-meter hole-patterned surfaces, which shows hydrophobic textured surfaces. Moreover, the hydrophilic textured surfaces were manufactured by anodizing technique on the micro-meter hole-patterned surfaces to generate multi-layer surfaces. Impinging droplet experiments were conducted for various hole-patterned surfaces, with changing impact velocity and texture area fractions. It is observed that an anodizing technique increases wettability by decrease in hole diameter on the textured surfaces. However, micro-drilled surfaces decreases wettability because the hole diameter was so large that air can be trapped under the holes. In addition, the maximum spreading diameter decreases with the texture area fraction for the micro-drilled surfaces because of decrease in wettability.

• Journal of the Korean institute of surface engineering
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• v.35 no.5
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• pp.273-278
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• 2002

We oxidized pure titanium by anodizing oxidation process in the range of 590V, within 1.5A, 30seconds. we investigated color evolution with a spectrophotometer. Surface images and surface roughness were characterized by an optical microscope and an atomic force microscope, respectively. Below the thickness of 40 $\mu\textrm{m}$, metallic yellow, blue, and pink colorsn were obtained. Lightness decreased, increased, and decreased again as titanium oxide thickness increased. Blue color at the applied voltage of 30V showed the best lightness and reproducibility with surface roughness below l$\mu\textrm{m}$. Bare titanium and titanium oxide films had micro pits more than 10ea/$\mu\textrm{m}^2$. We report that we successfully made colors by varing thickness below 40$\mu\textrm{m}$ with anodizing oxidation of method.

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.4
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• pp.45-50
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• 2003

In order to investigate the effect of surface treatment (Anodizing) and rolling on AI 5083-H131 alloy, under hyper velocity impact, a ballistic testing was conducted. Ballistic resistance of these materials was measured by a protection ballistic limit ($V_{50}$)' a statistical velocity with 50% probability of penetration. Perforation behavior and ballistic tolerance, described by penetration modes, were respectfully observed, by $V_{50}$ test and Projectile Through Plates (PTP) test at velocities greater than $V_{50}$. PTP tests were conducted with 0$^{\circ}$ obliquity at room temperature using 5.56mm ball projectiles. $V_{50}$ tests with 0$^{\circ}$ obliquity were also done with projectiles that were able to achieve near or complete penetration during PTP tests. Resistance to penetration, and penetration modes of Al 5052-H34 alloy were compared to those of Al 5083-H 131 alloy.