• 제목/요약/키워드: candidate materials

검색결과 809건 처리시간 0.024초

Ti-6Al-4V 합금의 절삭특성과 FEM 해석 비교에 관한 연구 (A Study on the Cutting Characteristics and Analysis by a FEM in the Machining of Ti-6Al-4V alloy)

  • 김남용;홍우표;이동주
    • 한국공작기계학회논문집
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    • 제10권6호
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    • pp.29-35
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    • 2001
  • The cutting characteristics of Ti-6Al-4V alloy and total wear when machining Ti-6Al-4V alloy was studied to understand the machining characteristics. This material is one of the strong candidate materials present and future aerospace or met ical applications. Nowadays their usage has already been broaden to commercial applications such as golf club head, finger rings and many decorative items. Anticipating the general use of this material and development of the titanium alloy in domestic facilities, the review and the study of the machining parameters far those alloys are deemed necessary. This study is concentrated to the machining parameters of the Ti-6Al-4V alloy due to their dominant position in the production of tita mum alloys.

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터널내부 소음 저감을 위한 흡음제 요구성능에 관한 연구 (A Study on the Performance Requirement of Noise Absorbing Material for Railway tunnel)

  • 조준호;양신추;김형준;윤제원;김영찬
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2003년도 추계학술대회 논문집(III)
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    • pp.479-483
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    • 2003
  • In general, urban railroad in Korea is constructed as a tunnel type under ground due to the various restricted conditions. Passengers in train running through underground tunnel compare to open space are exposed to severe noise environment. In this study, various performance characteristics of many candidate materials are surveyed and analyzed. And some important characteristics are tested. From this study, various performance requirement for noise reduction in railway tunnel were suggested.

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고 포화 자화 및 우수한 고주파 특성을 가진 나노결정 FeCoTaN 박막의 제조 (Fabrication of Nanocrystalline FeCoTaN Magnetic Films Having High Saturation Magnetization and Excellent High Frequency Characteristics)

  • J. M. Shin;Kim, J.;Kim, Y. M.;S. H. Han;Kim, H. J.
    • 한국자기학회:학술대회 개요집
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    • 한국자기학회 2002년도 동계연구발표회 논문개요집
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    • pp.214-215
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    • 2002
  • High saturation magnetization (B$\_$s/) and excellent high frequency characteristics of magnetic thin films has been recognized as the most important requirement for further miniaturization and higher frequency operation in magnetic devices, such as magnetic heads and magnetic sensors. Up to now, Fe-X-N (X =Ti, Hf, and Al etc.) films with B$\_$s/ of 15 ∼ 19 kG and coercivity (H$\_$c/) of 0.5 ∼ 5.0 Oe have been successfully fabricated and proven to satisfy various requirements as a potential candidate for thin film head materials. (omitted)

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Development of Transparent Dielectric Paste for PDP

  • Kim, Hyung-Jong;Kyoung Joo;Auh, Ken-Ho
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1998년도 PROCEEDINGS OF THE 15TH KACG TECHNICAL MEETING-PACIFIC RIM 3 SATELLITE SYMPOSIUM SESSION 4, HOTEL HYUNDAI, KYONGJU, SEPTEMBER 20-23, 1998
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    • pp.79-83
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    • 1998
  • Plasma display panel is a potential candidate for HDTV, due to the fact hat the expansion of screen size is much easier using thick film technology. In this study, transparent dielectric materials using lead borosilicate glasses is developed, which satisfy the requirements of dielectrics for PDP. Paste is made of this glass composition. The paste has thixotropic behavior suitable for screen printing. The paste shows more thixotropic behavior as the particle size decrease. After firing, cross sectional area was analyzed by SEM. The void of fired thick film was removed using bimodal particle system. The dielectric showed good adhesion characteristics.

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p-n Heterojunction Composed of n-ZnO/p-Zn-doped InP

  • Shim, Eun-Sub;Kang, Hong-Seong;Kang, Jeong-Seok;Pang, Seong-Sik;Lee, Sang-Yeol
    • Transactions on Electrical and Electronic Materials
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    • 제3권1호
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    • pp.1-3
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    • 2002
  • A p-n junction was obtained by the deposition of an n-type ZnO thin film on a p-type Zn-doped InP substrate. The Zn-doped InP substrate has been made by the diffusion of Zn with sealed ampoule technique. The ZnO deposition process was performed by pulsed laser deposition (PLD). The p-n junction was formed and showed typical I-V characteristics. We will also discuss about the realization of an ultraviolet light-emitting diode (LED). The structure of n-ZnO/p-Zn-doped InP could be a good candidate for the realization of an ultraviolet light-emitting diode or an ultraviolet laser diode.

SHS법에 의한 15R-Sialon의 제조 및 특성 (Preparation and Properties of 15R-Sialon by SHS)

  • 김상섭;이온영;이철규;전병세
    • 한국세라믹학회지
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    • 제31권4호
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    • pp.407-414
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    • 1994
  • Compacts were prepared using the SHS(Self-propagating High-temperature Synthesis) method and nitrided at temperatures range from 145$0^{\circ}C$ to 175$0^{\circ}C$, and pressed at 180$0^{\circ}C$ under N2 atmosphere. The samples were characterized for bulk density, porosity, pore size and distribution, phase composition, microstructure and fracture toughness. Compacts were composed of whiskers, which showed a good candidate for the composite materials. The major phases of the compacts nitrided at 175$0^{\circ}C$ and pressed at 180$0^{\circ}C$ were 15R-sialon with a large aspect ratio.

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A Novel Metal Supported SOFC Fabrication Method Developed in KAIST: a Sinter-Joining Method

  • Bae, Joongmyeon
    • 한국세라믹학회지
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    • 제53권5호
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    • pp.478-482
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    • 2016
  • Metal-supported SOFCs have been investigated to overcome the disadvantages of ceramic-supported SOFCs, including issues related to mechanical strength and sealing. In the case of ceramic-supported cells, the mechanical support is a brittle ceramic or cermet, and it contains expensive materials. However, metal-supported cells utilize ceramic layers that are only as thick as necessary for electrochemical functioning, thereby compensating for the disadvantages of ceramic-supported cells. The mechanical support is fabricated from inexpensive and robust metals, and the electrochemically active layers are applied directly to the metal support. The metal-supported SOFCs thus can provide a reduced system cost, ease of manufacturing, and operational advantages. Owing to these features, metal-supported SOFCs are a very promising candidate for commercialization. Given the importance of studying worldwide trends in metal-supported SOFC research for performance evaluation, this paper reviews development trends with a focus on fabrication methods. Furthermore, a novel fabrication method developed in KAIST is discussed.

Polyamic Acid 알킬아민 염 랭뮤어-블로젯막의 분자 배향에 관한 연구 (A Study on the Molecular Orientation of Polyamic Acid Alkylamine Salt Langmuir-Blodgett Films)

  • 정순욱;임현성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 추계학술대회 논문집
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    • pp.53-56
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    • 2000
  • Langmuir-Blodgett(LB) technique is the best candidate for the future molecular electronic devices. But, these molecular thin film devices require the bulk properties that are influenced by the molecular orientations. So, this is of current interest in molecular electronic device fabrications of new materials. In this study, quantitative evaluation of molecular orientation in LB films of PAAS was performed by comparing the absorption intensities of the FT-IR transmission and reflection-absorption spectra and the polarized UV/visible absorption spectra. It was found that the polar angle( $\theta$ ) of the dipole moment is about 68$^{\circ}$ and the tilting angle of the alkyl chain is about 11.5$^{\circ}$

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3차원 ZnO 나노구조체 가스센서 (3-dimensional nanostructured ZnO gas sensor)

  • 박용욱;신현용;윤석진
    • 센서학회지
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    • 제19권5호
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    • pp.356-360
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    • 2010
  • Due to the high surface-to-volume ratio, the 3-dimensional(3D) nanostructures of metal oxides are regarded as the best candidate materials for the chemical gas sensors. Here we have synthesised flower-like 3D zinc oxide nanostructures through a simple hydrothermal route. Specific surface area of the 3D zinc oxide nanostructures synthesised in different pH values from 9.0 to 12.0 were evaluated by using a BET analyzer and the results were compared with that of a zinc oxide thin film fabricated by rf sputtering. Using interdigitated electrodes, superior CO gas sensing properties of the 3D zinc oxide nanostructures on the ZnO thin film to those of the ZnO thin film were demonstrated.

코팅과 열처리가 연료전지 분리판의 내식성에 미치는 영향 (Effect of the Coaling and Annealing on Noncorrosive of Fuel Cell Separator)

  • 김귀열
    • 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.