• 제목/요약/키워드: multi-coating

검색결과 287건 처리시간 0.028초

Incoloy 909 합금의 최적 알루미나이징 확산 코팅 (Optimal Aluminizing Coating on Incoloy 909)

  • 권순우;윤재홍;주윤곤;조동율;안진성;박봉규
    • 한국표면공학회지
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    • 제40권4호
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    • pp.175-179
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    • 2007
  • An Fe-Ni-Co based superalloy Incoloy 909 (Incoloy 909) has been used for gas turbine engine component material. This alloy is susceptible to high temperature oxidation and corrosion because of the absence of corrosion resistant Cr. For the improvement of durability of the component of Incoloy 909 aluminizing-chromate coating by pack cementation process has been investigated at relatively low temperature of about $550^{\circ}C$ to protect the surface microstructure and properties of Incoloy 909 substrate. As a previous study to aluminizing-chromate coating by pack cementation of Incoloy 909, the optimal aluminizing process has been investigated. The size effects of source Al powder and inert filler $Al_O_3$ powder and activator selection have been studied. And the dependence of coating growth rate on aluminizing temperature and time has also been studied. The optimal aluminizing process for the coating growth rate is that the mixing ratio of source Al powder, activator $NH_4Cl$ and filler $Al_O_3$ are 80%, 1% and 19% respectively at aluminizing temperature $552^{\circ}C$ and time 20 hours.

고속 화염 용사 공정을 이용한 스위칭 소자용 BCuP-5 filler 금속/Ag 기판 클래드 소재의 제조, 미세조직 및 접합 특성 (Fabrication, Microstructure and Adhesion Properties of BCuP-5 Filler Metal/Ag Plate Clad Material by Using High Velocity Oxygen Fuel Thermal Spray Process)

  • 주연아;조용훈;박재성;이기안
    • 한국분말재료학회지
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    • 제29권3호
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    • pp.226-232
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    • 2022
  • In this study, a new manufacturing process for a multilayer-clad electrical contact material is suggested. A thin and dense BCuP-5 (Cu-15Ag-5P filler metal) coating layer is fabricated on a Ag plate using a high-velocity oxygen-fuel (HVOF) process. Subsequently, the microstructure and bonding properties of the HVOF BCuP-5 coating layer are evaluated. The thickness of the HVOF BCuP-5 coating layer is determined as 34.8 ㎛, and the surface fluctuation is measured as approximately 3.2 ㎛. The microstructure of the coating layer is composed of Cu, Ag, and Cu-Ag-Cu3P ternary eutectic phases, similar to the initial BCuP-5 powder feedstock. The average hardness of the coating layer is 154.6 HV, which is confirmed to be higher than that of the conventional BCuP-5 alloy. The pull-off strength of the Ag/BCup-5 layer is determined as 21.6 MPa. Thus, the possibility of manufacturing a multilayer-clad electrical contact material using the HVOF process is also discussed.

세라믹공구 재료의 피복특성에 관한 연구 (A Study on the Coated Characteristics of Ceramic Tools)

  • 이명제;임홍섭;유봉환
    • 대한기계학회논문집A
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    • 제24권4호
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    • pp.900-906
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    • 2000
  • Ceramic, PCD and CBN tools are available for the difficult-to-cut-materials such as hardened carbon tool steel, stainless steel, Inconel 718 and etc. Ceramic tools are likely to be chipped and abruptly broken before the appearance of normal wear in turning. Ceramic tools are suitable for continuous in turning, not for intermittent in milling. In this study, TiN/TiCN multi-layer coated ceramic tools were found to restrain the chipping, breaking and early fracture and to increase the critical cutting speed owing to TiN/TiCN multi-layer coating in Arc Ion Plating of PVD method.

Multi-mode Planar Waveguide Fabricated by a (110) Silicon Hard Master

  • Jung, Yu-Min;Kim, Yeong-Cheol
    • 한국전기전자재료학회논문지
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    • 제18권12호
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    • pp.1106-1110
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    • 2005
  • We fabricated (110) silicon hard master by using anisotropic wet etching for embossing. The etching chemical for the silicon wafer was a TMAH $25\%$ solution. The anisotropic wet etching produces a smooth sidewall surface and the surface roughness of the fabricated master is about 3 nm. After spin coating an organic-inorganic sol-gel hybrid material on a silicon substrate, we employed hot embossing technique operated at a low pressure and temperature to form patterns on the silicon substrate by using the fabricated master. We successfully fabricated the multi-mode planar optical waveguides showing low propagation loss of 0.4 dB/cm. The surface roughness of embossed patterns was uniform for more than 10 times of the embossing processes with a single hydrophobic surface treatment of the silicon hard master.

당뇨병 환자의 혈당치 측정을 위한 다층 젤라틴 필름을 이용한 진단막의 제조에 관한 기초연구 (Basic Studies on the Preparation of Diagnostic Membranes by Using Multi-Layered Gelatin Films to Measure Blood Glucose Level of Diabetics)

  • 권석기;음성진
    • 멤브레인
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    • 제8권1호
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    • pp.22-28
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    • 1998
  • 혈중 글루코우즈의 농도를 측정하기 위한 진단막의 제조를 위해 다층 젤라틴 필름이 사용되었다. 혈당치를 얻기위해 glucose dehydrogenase와 diaphorase를 이용하여 다층 젤라틴 필름을 통과하는 글루코우즈의 확산속도를 측정하였다. 글루코우즈의 최대 확산속도에 미치는 코팅의 간격거리, 효소의 양, 필름의 두께, 그리고 외부 온도의 영향에 대해 조사하였다.

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CNT/PMMA 복합막 검출기의 유기화합물 증기의 검출 특성 (Organic Compounds Vapor Detection Properties of MWCNT/PMMA Composite Film Detector)

  • 임영택;신백균;이선우
    • 한국전기전자재료학회논문지
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    • 제28권11호
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    • pp.727-730
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    • 2015
  • In this paper, we fabricated organic compounds detector using the MWCNT/PMMA (multi-walled carbon nanotube / polymethylmethacrylate) composite film. We used polymer film as a matrix material for the device framework, and introduced CNTs for reacting with the organic compounds resulting in changing electrical conductivity. Spray coating method was used to form the MWCNT/PMMA composite film detector, and pattern formation of the detector was done by shadow mask during the spray coating process. We investigated changes of electrical conductivity of the detector before and after the organic compounds exposure. Electrical conductivity of the detector tended to decrease after the exposure with various organic compounds such as acetone, tetrahydrofuran (THF), toluene, and dimethylformamide (DMF). Finally we conclude that organic compounds detection by the MWCNT/PMMA composite film detector was possible, and expect the feasibility of commercial MWCNT/PMMA composite film detector for various organic compounds.

The Effect of Anodizing on the Electrical Properties of ZrO2 Coated Al Foil for High Voltage Capacitor

  • Chen, Fei;Park, Sang-Shik
    • Applied Science and Convergence Technology
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    • 제24권2호
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    • pp.33-40
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    • 2015
  • $ZrO_2$ and Al-Zr composite oxide film was prepared by vacuum assisted sol-gel dip coating method and anodizing. $ZrO_2$ films annealed above $400^{\circ}C$ have tetragonal structure. $ZrO_2$ layers inside etch pits were successfully coated from the $ZrO_2$ sol. The double layer structures of samples were obtained after being anodized at 100 V to 600 V. From the TEM images, it was found that the outer layer was $Al_2O_3$, the inner layer was multi-layer of $ZrO_2$, Al-Zr composite oxide and Al hydrate. The capacitance of $ZrO_2$ coated foil exhibited about 28.3% higher than that of non-coating foil after being anodized at 100 V. The high capacitance of $ZrO_2$ coated foils anodized at 100 V can be attributed to the relatively high percentage of inner layer in total thickness. The electrical properties, such as withstanding voltage and leakage current of coated and non-coated Al foils showed similar values. From the results, $ZrO_2$ and Al-Zr composite oxide is promising to be used as the partial dielectric of high voltage capacitor to increase the capacitance.

통전성형 금형 부품 절연을 위한 Si-DLC코팅 기계적 특성 연구 (A Study on the Mechanical Property of Sillicon Diamond-like-carbon Coating for Insulation of Electrically Assisted Forming Die Component)

  • 김우영;이현우;양대호;홍성태
    • 한국자동차공학회논문집
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    • 제23권6호
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    • pp.656-662
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    • 2015
  • In the present study, multi-layered Si DLC (Silicon Diamond-Like Carbon) coatings with HMDSO (Hexamethyldisiloxane) buffer layers are applied on SKD 11 substrates by PECVD (Plasma Enhanced Chemical Vapor Deposition) with different HMDSO gas flow rates, while the gas flow rate of $C_2H_2$ is fixed to enhance the electric resistivity of forming dies for electrically assisted forming. The HMDSO buffer layer is introduced to increase adhesion between the base metal and Si-DLC layers. The result of evaluation of electric resistivity and adhesion strength shows that the properties are affected by the flow rate of HMDSO, while the flow rate of 80 sccm results in the coating with the highest electric resistivity and adhesion strength among the selected flow rates.

PEDOT를 이용한 CRT용 반사방지 및 대전방지 코팅 (An Antireflection and Antistatic Coatings for CRTs using PEDOT)

  • 김태영;김종은;이보현;서광석;김진열
    • 한국전기전자재료학회논문지
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    • 제15권1호
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    • pp.61-66
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    • 2002
  • A method for designing antireflection (AR) and antistatic (AS) coating layer by the use of conducting polymer as an electrically conductive transparent layer is proposed. The conducting AR coating is composed of four-layer with alternating high and low refractive index layer: silicon dioxide (n=1.44) and titanium dioxide (n=2.02) prepared at low temperature by sol-gel method are used as the low and high refractive index layer, respectively. The poly(3,4-ethylenedioxythiophene) which has the surface resistivity of 10$^4$Ω/$\square$ is used as a conductive layer. Optical constant of each ARAS coating layers such as refractive index and optical thickness were measured by 7he spectroscopic ellipsometer and from the measured optical constants the spectral properties such as reflectance and transmittance were simulated in the risible region. The reflectance of ARAS films on glass substrate was below 1 %R and the transmittance was higher than 95 % in the visible wavelength (400-700 nm). The measured AR spectral properties was very similar to its simulated results.

IrO2 기반 수처리용 산화 전극의 표면 이종 접합 구성에 따른 활성 염소종 발생 증진 특성 연구 (A study on reactive chlorine species generation enhanced by heterojunction structures on surface of IrO2-based anodes for water treatment)

  • 홍석화;조강우
    • 상하수도학회지
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    • 제32권4호
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    • pp.349-355
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    • 2018
  • This study interrogated multi-layer heterojunction anodes were interrogated for potential applications to water treatment. The multi-layer anodes with outer layers of $SnO_2/Bi_2O_3$ and/or $TiO_2/Bi_2O_3$ onto $IrO_2/Ta_2O_5$ electrodes were prepared by thermal decomposition and characterized in terms of reactive chlorine species (RCS) generation in 50 mM NaCl solutions. The $IrO_2/Ta_2O_5$ layer on Ti substrate (Anode 1) primarily served as an electron shuttle. The current efficiency (CE) and energy efficiency (EE) for RCS generation were significantly enhanced by the further coating of $SnO_2/Bi_2O_3$ (Anode 2) and $TiO_2/Bi_2O_3$ (Anode 3) layers onto the Anode 1, despite moderate losses in electrical conductivity and active surface area. The CE of the Anode 3 was found to show the highest RCS generation rate, whereas the multi-junction architecture (Anode 4, sequential coating of $IrO_2/Ta_2O_5$, $SnO_2/Bi_2O_3$, and $TiO_2/Bi_2O_3$) showed marginal improvement. The microscopic observations indicated that the outer $TiO_2/Bi_2O_3$ could form a crack-free layer by an incorporation of anatase $TiO_2$ particles, potentially increasing the service life of the anode. The results of this study are expected to broaden the usage of dimensionally stable anodes in water treatment with an enhanced RCS generation and lifetime.