• Proceedings of the Membrane Society of Korea Conference
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• 1994.04a
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• pp.57-57
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• 1994

졸-겔 침지코팅 (dipcoating) 또는 가압 졸-겔 코팅 (pressurized coating) 법으로 제조한 $\gamma-Al_2O_3, SiO_2, TiO_2$ 및 aluminosilicate 복합막에 대하여 $CO_2$, He, $N_2$, 및 $O_2$ 기체 투과율과 $CO_2$ 분리계수를 측정하였다. 이들 막을 통한 모든 기체의 이동은 Knudsen 유동이 지배적이었으며 $CO_2/N_2$의 분리계수는 0.9 ~ 1.1 정도로 Knudsen 분리계수 ($CO_2/N_2$의 경우 0.8)보다 약간 높은 값을 보여주었다. $CO_2$ 분리계수를 향상시키기 위하여 silane coupling 및 산화물 도핑법에 의한 복합막의 표면개질을 시도하였으며 분리막의 재질 및 표면개질 조건에 따른 $CO_2/N_2$ 분리계수 변화를 측정 비교하였다. Silane coupling에 의한 표면개질이 $CO_2$의 표면 친화성 (affinity)에 의한 표면확산속도를 증가시키기 때문에 $CO_2$ 분리에 있어서 산화물 도핑에 의한 표면개질보다 더욱 효과적이었다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.105-106
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• 2017

The metal spray method, one of the surface anti-corrosion methods to prevent the corrosion of the steel material, does little effects on the material, while it can be used on a wider surface. However, metal spraying is used only in a limited environment, and research on the case of using with concrete is lacking. The purpose of this study was to observe the corrosion behavior of steels with metal spray coatings in concrete using electrochemical methods And to evaluate the performance of the method according to the type of metal used in the metal spray. As a result, the Al metal spray coating showed the best performance, because Aluminum is oxidized in the cement mortar and forms alumina oxide film.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.8
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• pp.33-38
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• 1998

TiYN coated high speed steel tools have been developed and their tool lifes were assessed. First yttrium alloyed titanium target was manufactured, then using the arc ion plating(AIP) technique TiYN coating was deposited onto high speed steel substrate. Three kinds of varying thickness of TiYN coated tools were prepared. Cutting tests were carried out with theses tools and for comparison with the commercially available uncoated, TiN, TiCN and TiAlN coated tools. During the cutting tests flank wear width vs. cutting time was measured. It has been revealed that the newly developed TiYN coated tools show superior tool life characteristics to others.

• Korea-Australia Rheology Journal
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• v.13 no.4
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• pp.179-187
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• 2001

As part of continuing efforts to investigate nonlinear dynamics and stability of film casting process, our earlier results obtained by Lee et al. (2001b) have been extended in the present study to cover the film casting of both extension thickening and extension thinning fluids. The same instability mechanism and draw resonance criterion previously derived have been found valid here, and a rather complex dynamic behavior of film width in contrast to that of film thickness has also been confirmed. The effect of fluid viscoelasticity on draw resonance, however, exhibits opposite results depending on whether the fluid is extension thickening or thinning, i.e., it stabilizes film casting in the former while destabilizing in the latter. The encapsulation extrusion method which recently has been successfully employed to stabilize industrially important paper coating process, has been theoretically explained in the present study as to why such stabilization is possible.

• Proceedings of the KWS Conference
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• 2003.05a
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• pp.114-116
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• 2003

The multi function sprayed coating is used for direct-heating, wear resistance and high bonding strength. The merits of surface direct-heating coatings are short warming time, low power consumption and better wear resistance that can be used in many organization parts. In this study, the surface direct-heating and wear resistance can be improved by spraying the proper materials on the surface $Al_2$O$_3$40%TiO$_2$ powder and Ni-20%Cr powder that had the properties of conduction and high wear resistivity are used in order to improve wear resistance, electrical properties and bonding strength.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.205-205
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• 2015

PVD 기술이 반도체나 LCD 등의 전자산업에서 주력기술로 성장하는 과정에서, 금속 Strip 소재에 연속적으로 PVD 코팅을 실시하기 위한 연구개발과 상용화 노력이 진행되어왔다. 이미 1960년대에 강판 표면에 Al을 증착시키기 위한 공정이 상용화된 실적이 있었지만, 전기도금이나 용융도금에 비해 기술의 확산이 빠르게 이루어지지 않았고, 1980년대 후반에 일본에서 전기도금을 대체하기 위한 공정으로 상용화공정을 건설하였지만, 결국은 경제성을 확보하지 못하여 도태되는 과정을 겪어왔다. 하지만, 1990년대 이후 유럽과 한국을 중심으로 연속코팅기술에 대한 연구개발이 꾸준히 진행되어 왔으며, 최근 이슈가 되고 있는 자동차용 초고강도강의 코팅기술로 PVD 기술이 재조명되고 있다.

• Journal of the Korean institute of surface engineering
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• v.33 no.1
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• pp.38-47
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• 2000

A Ti(CN) layer was formed on aluminum alloy by using diethylamino titanium, hydrogen and nitrogen with the pulsed DC PACVD process. Effect of process parameters such as precursor evaporation temperature, duty ratio, frequency, voltage, $H_2$/$N_2$gas ratio on the properties of Ti(CN) layer were investigated. The layer thus obtained had high hardness and low friction coefficient. Detailed results on the hardness, surface morphology, XRD, WDS analysis, wear test and scratch test of this layer are presented.

• Transactions on Electrical and Electronic Materials
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• v.8 no.6
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• pp.283-285
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• 2007

The molten carbonate fuel cell has conspicuous feature and high potential in being used as an energy converter of various fuel to electricity and heat. However, the molten carbonate fuel cell which use strongly corrosive molten carbonate at $650^{\circ}C$ have many problem. Systematic investigation on corrosion behavior of stainless steels has been done 62 mole% $Li_2CO_3$ and 38 mole% $K_2CO_3$ melt at 923 K by using steady-state polarization method and electrochemical impedance spectroscopy method. It was found that SUS 310L and Al coating specimen may be the best choice among the alloys tested in this study for molten carbonate fuel cell component material.

• Korean Journal of Crystallography
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• v.19 no.1
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• pp.25-30
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• 2008

In order to characterize the optical properties of CdS thin films and CdS powders, the following experiments were performed: CdS wurtzite thin films were made using 99.99% CdS (Aldrich) powder and the $AlO_x$ membranes in $7{\times}10^{-6}$ torr(here, the average vacuum coating speed is $1{\AA}/sec$.). The surface states of CdS nano-particles with dimensions of 3.87 nm were studied through the fluorescence spectroscopy. From the resulting spectra exhibited, we can see a sharp fluorescence at 451 nm arising from the excitons on the CdS thin films, compared with the 448nm peak of the CdS powders.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1213-1214
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• 2006

The synthesis of silver coated iron base alloy (Sendust : Fe-Si-Al) powder having the both effects of shielding and suppressing of electromagnetic wave was studied. Depending on thickness of silver coating layer, the electromagnetic properties of the dispersed particles complexed with organic binder were examined. It is proposed that the silver coated sendust flake powders with controlled electrical properties and thickness can be used as thin microwave absorbers in quasi-microwave frequency band.