• 한국세라믹학회지
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• 제47권6호
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• pp.633-637
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• 2010

In this study, lithium manganese oxide spinel ($LiMn_{1.9}Fe_{0.1}Nb_{0.0005}O_4$) as a cathode material of lithium ion secondary batteries is synthesized with spray drying, and in order to increase its crystallinity and electrochemical properties, the granulated $LiMn_{1.9}Fe_{0.1}Nb_{0.0005}O_4$ particle surface is coated with lithium titanium oxide spinel ($Li_4Ti_5O_{12}$) through a sol-gel method. The granulated particles present a higher tap density and lower specific surface area. The crystallinity and discharge capacity of the $Li_4Ti_5O_{12}$ coated material is relatively higher than uncoated material. With the coating layer, the discharge capacity and cycling stability are increased and the capacity fading is suppressed successfully.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.101-101
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• 2010

A strong adhesion of a silicon carbide (SiC) coating on a WC-Co substrate was achieved through an ion beam mixing technique and the corrosion resistance of the SiC coated WC-Co was investigated by means of a potentiodynamic electrochemical test. In the case of 1 M NaOH solution, a corrosion current density for a SiC coated WC-Co with a heat treatment at $500^{\circ}C$ displays about 50 times lower than that for the as-received WC-Co. However, in the case of 0.5 M H2SO4 solution, a corrosion current density for a SiC coated WC-Co displays about 3 times lower than that for as-received WC-Co. We discussed the physical reasons for the changes of the corrosion current densities at the different electrolytes.

• 한국표면공학회지
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• 제28권4호
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• pp.199-206
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• 1995

A kinetic study on the electrodeposition of Ni-Zn-P ternary alloys onto a steel in chloride solutions was carried out using a rotating disc electrode. The coatings were characterized using SEM/EPMA and A. A. analysis. The results showed that the plating rates of three components were increased with applied potential, disc rotating speed and temperature. The activation energies of Ni, Zn and P of the coatings were 6.1, 5.1 and 8.0 kcal/mole respectively. Therefore, the deposition rates were controlled partly by surface electrochemical reaction and partly by mass transport. As the potential, temperature of bath and rotating speed of cathode disc were raised, the vol. % ratios of Ni and P of coating layer were increased but that of Zn decreased. The effect of coating parameters on the surface morphology was also examined.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2016년도 추계학술대회 논문집
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• pp.168-168
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• 2016

최근 크로메이트 피막의 대체로서 실란 커플링제를 사용한 화성처리가 주목되고 있다. 실란 커플링제는 $R^{\prime}-(CH_2)_n-Si(OR)_3$로 나타내며 OR은 가수분해 가능한 메톡시기, 에톡시기 등의 알콕시기이다. OR기는 가수분해하여 반응성이 높은 시라놀기(-SiOH)를 생성하여 금속표면에 흡착하기 쉽다. 이후, 건조할 때 탈수 축합하여 공유결합이 가능하다. R'는 탄화수소에 한정되지 않고 성질이 다른 원소의 관능기를 나타내며 아미노(amino)기, 글리시딜(glycidyl)기, 멜캅토(melcapto)기, 비닐(vinyl)기를 들 수 있다. 실란 커플링제 가운데 아미노기를 갖는 실란 커플링제는 아연도금 강판을 포함한 다양한 금속의 내식성을 향상시킬 수 있는 화합물의 하나이다. 본 연구에서는 아미노기를 함유한 실란 커플링제에 인산 수용액을 도포하여 수세하지 않고 건조하여 피막을 형성시켰다. 또 부식거동 조사를 목적으로 아미노기를 함유한 실란 커플링제를 사용하여 초산첨가의 경우와 비교하였다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2013년도 춘계학술대회 논문집
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• pp.150-150
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• 2013

Al-Mg films were prepared onto steel sheet according to deposition condition by eco-friendly electron beam vacuum evaporation method. The influence of Al-Mg films on corrosion resistance was evaluated by salt spray test and electrochemical method etc.. From the experimented results, it was found that the Al-Mg films which showed good corrosion resistance tend to have fine structure with homogenious composition distribution. In addition, it was shown that the property of coating films can be improve by controlling thickness ratio and uniform distribution of intermetallic compounds in Al-Mg films.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.221-222
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• 2008

In Crystalline Si solar cells, Anti-Reflection Coating is contribute to improvement in energy conversion efficiency due to decrease of optical loss and recombination owing to surface passivation. Porous Si is formed electrochemical etching that uses chemical solution and anodization etching. So It gives that advantage in rapid process time and without high cost equipment. In this paper, We compare Porous Si with $SiO_2$/SiNx ARC and analyze that by anti-reflection coating.

• Bulletin of the Korean Chemical Society
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• 제33권4호
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• pp.1177-1182
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• 2012

The corrosion resistance of 316L stainless steel coated with NiO-YSZ (Ni added yttria stabilized zirconia) was examined in a proton exchange membrane fuel cell (PEMFC) environment. The NiO-YSZ coating was carried out using a sol-gel dip coating method, and the corrosion resistance and interfacial contact resistance (ICR) were determined by the composition and morphology of the NiO-YSZ film. The corrosion resistance increased with increasing Ni content in the NiO-YSZ film, but rapid corrosion was observed when the YSZ film contained more than 15 wt % Ni due to surface cracks. The polarization resistance was improved by several orders of magnitude when 316L stainless steel was coated with a 15 wt % NiO-YSZ film compared to bare 316L. The ICR of the NiO-YSZ film was decreased to that of bare 316L when the YSZ film contained 25 wt % NiO, suggesting the possible application of NiO-YSZ coated stainless steel for a bipolar plate.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2008년도 추계학술대회 초록집
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• pp.155-157
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• 2008

High velocity oxy-fuel (HVOF) thermal spraying coating has been used widely throughout the last 60 years mainly in defense, aerospace, and power plants. Recently this coating technique is considered as a promising candidate for the replacement of the traditional electrolytic hard chrome plating (EHC) which pollutes the environment and causes lung cancer by toxic hexa-valent $Cr^{6+}$. In this study, two kinds of cermet coatings, WC-CoCr and WC-CrC-Ni, are formed by HVOF spraying. The corrosion and electrochemical properties are evaluated by polarization tests in 3.5 wt% solutions.

• 한국전기전자재료학회논문지
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• 제20권11호
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• pp.1000-1003
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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. One of the material problems is the severe corrosion of the metallic components, such as the separator. The effect of coating and annealing treatment on the corrosion for SUS 304 and SUS 430 which are the candidate materials for molten carbonate fuel cell hardware has been investigated in molten carbonate at $650^{\circ}C$ by using steady state polarization and electrochemical impedance spectroscopy method. It was found that the corrosion current of these SUS 304 and SUS 430 decreased with coating and annealing treatment.

• 한국표면공학회지
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• 제45권4호
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• pp.162-167
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• 2012

Ni-P/C multi-layer was synthesized by electroless plating and paste coating for better corrosion and surface conductance as a metallic bipolar plate. The Ni-P layer could be synthesized with the range of 2.6~22.4 at.% P contents and it's surface morphology and corrosion resistance depend on content of P. Corrosion resistance of the Ni-P layer in sulfuric acid by electrochemical test is similar with pure Ni. Surface resistance of pure Ni after corrosion was increased about 8% compared to pure Ni. On the other hand, that of the Ni-P/C composite with 20% carbon content was increased only 1%.