• 한국표면공학회지
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• 제26권2호
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• pp.45-54
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• 1993

In this study, magnetic properties of anodized Al film deposited with ferro-magnetic metals in the capacity of perpendicular magnetic recording media were measured and evaluated to find out the role of structure and morphology of the oxide films on magnetic characteristics. The object of this work was to present the conditions of magnetic thin film formation with more superior magnetic property. Anodizing was carried out under various conditions, and then the anodized film were electro-deposited with Co, Ni, Fe and their alloys. Coercive force and residual magnetization in perpendicular direction increased as the pore length of anodized film increased. It was attributed to the increase of the amount of depoisted metals and the ratio of length/diameter of pores. Morphology of anodized films in phosperic acid was not similar to that of sulfuric acid, and thin films in the former solution had perpendcular magnetic anisostropy because of large diameter, irregular length and distribution of the pores. It was found that magnetic properties of the thin films, which had doubled layer of two metals, were dominated by the metal electrodeposited on the surface of the anodized oxide films.

• 한국표면공학회지
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• 제53권1호
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• pp.36-42
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• 2020

In this study, two novel methods to measure the surface hardness of anodic oxide films on aluminum alloys are reported. The first method is to impregnate oil-based ink into pores in the anodic oxide film and then to clean the ink on the surface using ethanol, resulting in an impregnation of inks only inside of the pores in anodic oxide film. The second method is to coat the anodic oxide film surface with thin Au layer less than 0.1 ?. Both the ink-impregnating method and Au-coating method provided clear indentation marks on the anodic oxide film surface when it was indented using a pyramidal-diamond penetrator. Thus, Vickers hardness of anodic oxide films on aluminium alloy could be measured successfully and precisely from the anodic film surface. In addition, advantages and disadvantages of the ink-impregnating method and Au-coating method for the measurement of surface hardness of anodic oxide films are discussed.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2003년도 학술대회논문집
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• pp.227-232
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• 2003

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.

• 한국표면공학회지
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• 제23권3호
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• pp.150-159
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• 1990

The magnetic properties of electrodeposited iron and cobalt films on porous aluminum oxide film were examined. There exists perpendicular magnetic anisotropy due to the shape anisotropy. The coercivity and squareness ratio of films were strongly dependent on deposited particle diameter. The effect of packing fraction on squareness ratio was also apprecible. Unlike the iron-deposited films, the magnetic properties of cobalt films were changed by preferred orientation because of it's large crystal ansotropy constant.(about 10 times of Fe) The Fe deposited films were found to be more suitable for perpendicular magenetic recording media bacause perpendicular coercivity, squareness ratio and the ratio of perpendicular coercivity to horizontal ones of iron films are greater than those of cobalt films.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.106-107
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• 2007

We fabricated anodic aluminium oxides (AAO) on Si and sapphire substrates from the electrochemical reactions of thin AI films in an aqueous solution of oxalic acid. The thin AI films have deposited on Si and Sapphire substructure by using E-beam evaporation and thermal evaporation, respectively. The formation of AAO structures has investigated from FE-SEM measurement image and showed randomly distributed phase of nanoholes instead of the periodic lattice of photonic crystals. The AAO structure on sapphire shows the double layers of nanoholes.

• 소성∙가공
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• 제19권2호
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• pp.73-78
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• 2010

Recently, many researches on the development of super-hydrophobic surface have been concentrated on the fabrication of nano-patterned products. Nano-patterned mold is a key to replicate nano-patterned products by mass production process such as injection molding and UV molding. The present paper proposes the new fabricating method of nano-patterned mold at low cost. The nano-patterned mold was fabricated by electroforming the anodic aluminum oxide membrane filled with UV curable resin in nano-hole by capillary phenomenon. As a result, the final mold with nano-patterns which have the holes with the diameter of 100~200 nm was fabricated. Furthermore, the UV-molded products with clear nano- patterns which have the pillars with the diameter of 100~200nm were achieved.

• 한국표면공학회지
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• 제33권5호
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• pp.309-318
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• 2000

The 6063 Aluminium alloy were electrocolored and anodized at the same time in addition of $CoSO_4$, $FeSO_4$, in the electrolyte and investigated by AES/SAM. It was found that the thickness of anodic oxide film is increased linearly in DC type, and DC combined AC type, the more ratio of anodic Portion in AC, the more increased of anodic film thickness. The color of anodic film was changed from silver to yellow when the increase of the ratio of cathodic portion in AC. Also the increase of $CoSO_4$, $FeSO_4$ in the electrolyte, the coloring time is decreased. From the AES/SAM results, the element of anodic oxide film are Al,O and S. The result of depth profile, the most of the S distributed on the surface and the more S is in DC combined AC type than only DC type.

• 정보저장시스템학회논문집
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• 제9권2호
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• pp.67-71
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• 2013

The fabrication method of plasmonic nanodots on silicon substrate has been developed to improve the efficiency of thin film solar cells. Nanoscale metallic nanodots arrays are fabricated by anodic aluminum oxide (AAO) template mask which can have different structural parameters by varying anodization conditions. In this paper, the structural parameters of gold nanodots, which can be controlled by the diverse structures of AAO template mask, are investigated to enhance the optical properties of a-Si thin film solar cells. It is found that optical properties of the thin film solar cells are improved by finding optimization values of the structural parameters of the gold nanodot array.

• 한국표면공학회지
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• 제55권6호
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• pp.417-424
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• 2022

This research develops an easy-to-use, environmentally friendly method for fabricating functional 1050 aluminum alloy surfaces with excellent corrosion resistance. Functional aluminum surfaces with various nanostructures are fabricated by controlling the experimental conditions of anodizing process. The experiment used a multi-step anodizing process that alternates between two different anodizing modes, mild anodizing (MA) and hard anodizing (HA), together with a pore-widening (PW) process. Among them, the nanostructured surface with a small solid fraction shows superhydrophobicity with a contact angle of more than 170° after water-repellent coating. In addition, the surface with superhydrophobicity is difficult for corrosive substances to penetrate, so the corrosion resistance is greatly improved.

• Corrosion Science and Technology
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• 제21권6호
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• pp.495-502
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• 2022

Anodization is a representative electrochemical surface treatment method that can improve both heat resistance and corrosion resistance by forming an anodization film on the surface of the aluminum. However, these properties can be changed after an additional heat treatment process. In this study, Al 6061 was subjected to an anodization process at 60 V for 1 hour, 5 hours, or 9 hours. An additional heat treatment process was performed at 500 ℃ for 30 minutes. Field emission scanning electron microscopy (FE-SEM) analysis revealed that the thickness of the anodized film was increased in proportion to the anodization time. Both pore size and pore diameter of the anodized film was also increased after anodization. After an additional heat treatment process, there were no significant changes in the thickness, pore size, or pore diameter of the anodized film. Heat resistance was confirmed through thermal analysis and chemical resistance was evaluated with a potentiodynamic polarization test.