• International Journal of Precision Engineering and Manufacturing
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• v.7 no.4
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• pp.18-22
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• 2006

Although many efforts have been made in making nanometer-sized holes, there is still a major challenge in fabricating individual single-digit nanometer holes in a more controllable way for different materials, size distribution and hole shapes. In this paper we describe our efforts to use a top down approach in nanofabrication method to make single-digit nanoholes. There are three major steps towards the fabrication of a single-digit nanohole. 1) Preparing the freestanding thin film by epitaxial deposition and electrochemical etching. 2) Making sub-micro holes ($0.2{\mu}\;to\;0.02{\mu}$) by focused ion beam (FIB), electron beam (EB), atomic force microscope (AFM), and others methods. 3) Reducing the hole size to less than 10 nm by epitaxial deposition, FIB or EB induced deposition and micro coating. Preliminary work has been done on thin films (30 nm in thickness) preparation, sub-micron hole fabrication, and E-beam induced deposition. The results are very promising.

• Ceramist
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• v.9 no.6
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• pp.24-29
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• 2006

Electron beam physical vapor deposition (EB-PVD) process has currently been applied to thermal barrier coatings (TBCs) for aircraft engines. Due to unique columnar structure, EB-PVD TBCs have advantages in resistances to thermal shock and thermal cycle for their applications, compared to films prepared by plasma spray By the EB-PVD equipment, we successfully obtained yttria-stabilized zirconia (YSZ) layer which has columnar and feather like structure including a large amount of nano size pores and gaps. The EB-PVD technique has been developed for coating functional perovskite type oxides such as (La, Sr)MnO3. Electrode properties have been improved by interface and structural control.

• Journal of the Korean Ceramic Society
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• v.42 no.2 s.273
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• pp.117-122
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• 2005

Electron Beam Physical Vapor Deposition (EB-PVD) is a typical technology for thermal barrier coating with Yttria Stabilized Zirconia (YSZ) on aero gas turbine engine. In this study EB-PVD method was used to fabricate dense YSZ film on NiO-YSZ as a electrolyte of Solid Oxide Fuel Cell (SOFC). Dense YSZ films of -10 $\mu$m thickness showed nano surface structure depending on deposition temperature. Electrical conductivities of YSZ film and electric power density of the single cell were evaluated after screen- printing $LaSrCoO_3$ as a cathode.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.3
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• pp.83-88
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• 2015

Coating materials used in the electron beam (EB) deposition method, which is being studied as one of the fabrication methods of thermal barrier coating, are exposed to high power electron beam at focused area during the EB deposition. Therefore the coating source for EB process is needed to form as ingot with appropriate density and microstructure to sustain their shape and stable melts status during EB deposition. In this study, we tried to find the optimum powder condition for fabrication of ingot of 8 wt% yttria stabilized zirconia which can be used for EB irradiation. It seems that the ingot, which is fabricated through bi-modal type initial powder mixture which consists of tens of micro and nano size particles, was shown better performance than the ingot which is fabricated using monolithic nanoscale powder when exposed to high power EB.

• Journal of the Korean institute of surface engineering
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• v.46 no.6
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• pp.258-263
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• 2013

4 mol% Yttria-stabilized zirconia (4YSZ) coatings are fabricated by Air Plasma Spray (APS) and Electron Beam Physical Vapor Deposition (EB-PVD) with top coating of thermal barrier coating (TBC). NiCrAlY based bond coat is prepared as 150 ${\mu}m$ thickness by conventional APS (Air Plasma Spray) method on the NiCrCoAl alloy substrate before deposition of top coating. Each 4YSZ top coating shows different tribological behaviors based on the inherent layer structures. 4YSZ by APS which has splat-stacked structure shows lower friction coefficient but higher wear rate than 4YSZ by EB-PVD which has columnar structure. For 4YSZ by APS, such results are expected due to the sliding wear accompanied with local delamination of splats.

• Journal of the Korean institute of surface engineering
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• v.36 no.6
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• pp.423-429
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• 2003

It has been investigated corrosion resistance and crystal structure of Zn-Cr coatings fabricated by electroplating method and electron-beam physical vapor deposition method(EB-P VD). The electroplated Zn-Cr alloy consists mainly of η'-Zn phase for the lower Cr content than 7.9 wt% Cr and ${\gamma}$'-ZnCr phase for the higher Cr content. In the Zn-Cr alloy fabricated by EB-PVD the ${\gamma}$'-ZnCr phase appeared clearly at 3 wt% Cr and it became the sole phase at 50 wt%Cr. The amount of η'-Zn phase decreased obviously with increasing Cr content when it exceeded 15 wt% Cr. The electrochemical measurement of the electroplated Zn-Cr film has shown corrosion potential of about -1000 mV. The current density of active region and the amount of dissolved Zn and Cr decreased significantly with increasing Cr content. The electrochemical characteristics of Zn-Cr alloy fabricated by EB-PVD have shown that the alloy of 50 wt% Cr had the highest corrosion potential(-500 mV) and the lowest critical passive current density than that of the electroplated.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2006.05a
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• pp.350-356
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• 2006

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2002.05a
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• pp.50-50
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• 2002

탄소 박막은 내마모, 화학적 생물학적 적합성 둥의 특성으로 언하여 많은 연구자들레 의하 여 연구되어지고 있다. 그러나 탄소 박막의 경우 높은 잔류응력과 이에 따른 낮은 밀착력으 로 언하여 증착 두께에 제한이 되어왔다. EB-PVD법을 이용하여 탄소막을 증착하는 경우 이러한 문제점을 해결하기 위하여 탄소막에 제 2의 금속원소를 첨가하거나 화합물 형태의 증착원 이용, 복합공정 (Hybrid process)을 통하여 증착 두께 의 제 한을 극복하고자 하는 연 구가 계속되고 있다. 본 연구에서는 탄소막의 잔류응력 제어와 증착 두께를 높이기 위하여 Plasma Activated E E-Beam Evaporation을 통하여 탄소막을 증착하였다. 탄소막 증착시 잔류응려과 밀착력에 대한 플라즈마의 영향올 알아보기 위하여 RF 플라즈마의 인업 전력에 따라 실험을 수행하였으며 필라멘트 전자 방출원을 이용하여 플라즈마 밀도가 미치는 영향도 알아보았다.

• Journal of the Korean institute of surface engineering
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• v.39 no.4
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• pp.147-152
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• 2006

Failure mechanisms of electron beam physical vapor deposited thermal barrier coatings(EB-PVD TBCs) that occur during thermal cyclic oxidation were investigated. The investigations include microstructural degradation of NiCrAIY bond coat, thermally grown oxides(TGOs) along the ceramic top coat-substrate interface and fracture path within TBCs. The microstructural degradation of the bond coat during cyclic oxidation created Al depleted zones, resulting in reduction of NiAl and ${\gamma}$-Ni solid solution phase. It was observed that the fracture took placed primarily within the TGOs or at the interfaces between TGOs and bond coat.

• Journal of the Korean institute of surface engineering
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• v.34 no.3
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• pp.195-205
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• 2001

The surface characteristics of Ti/TiN films coated on sintered stainless steels (SSS) by electron beam physical vapour deposition (EB-PVD) were investigated. Stainless steel compacts containing 2, 4, and 10wt%Cu were prepared by the electroless Cu-plating method, which results in increased homogenization in the alloying powder. The specimens were coated with Ti and TiN with a 1.0$\mu\textrm{m}$ thickness respectively by EB-PVD. The microstructures were investigated using scanning electron microscopy (SEM). The corrosion behaviors were investigated using a potentiosat in 0.1 M $H_2$$SO_4$, and 0.1M HCl solutions and the corrosion surface was observed using SEM and XPS. The Ti coated specimens showed rough surface compared to Ti/TiN coated specimens. Ti and Ti/TiN coated SSS revealed a higher corrosion and pitting potential from anodic polarization curves than that of Ti and Ti/TiN uncoated SSS. In addition, Ti/TiN coated SSS containing 10wt% Cu exhibited good resistance to pitting corrosion due to the formation of a dense film on the surface and the decrease in interconnected porosity by electroless coated Cu.