• 제목/요약/키워드: Micro-structure of Spray

검색결과 21건 처리시간 0.031초

3차원 마이크로 구조를 위한 포토레지스트 스프레이 코팅 (Photoresist spray coating for three-dimensional micro structure)

  • 김도욱;은덕수;배영호;유인식;석창길;정종현;조찬섭;이종현
    • 센서학회지
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    • 제15권3호
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    • pp.153-157
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    • 2006
  • This paper presents the method for three-dimensional micro structure with photoresist spray coating system. The system consists of a high temperature rotational chuck, ultrasonic spray nozzle module, angle control module and nozzle moving module. Spray coating system is effected by several parameters such as the solid contents, the dispensed volume, the scanning speed of the spray nozzle and the wafer of dimension. The photoresist (AZ 1512) has been coated on the three-dimensional micro structure by spray coating system and the characteristics have been evaluated.

강제대류 및 핵비등영역에 있어서 마이크로 휜 형상이 분무냉각 열전달에 미치는 영향 (Effects of Micro-fin Structure on Spray Cooling Heat Transfer in Forced Convection and Nucleate Boiling Region)

  • 김영찬
    • 대한기계학회논문집B
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    • 제34권11호
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    • pp.983-990
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    • 2010
  • 본 연구에서는 냉각면의 표면온도가 비교적 낮은 강제대류 및 핵비등영역에서 다양한 종류의 마이크로 휜이 가공된 냉각면의 분무냉각 열전달에 대해 실험적으로 연구하였다. 실험결과로부터 냉각면 표면에 가공된 마이크로 휜은 분무냉각 열전달을 촉진시키며, 냉각휜의 크기와 종류에 상관없이 분무유량이 증가할수록 분무냉각 열전달도 큰 폭으로 증가하고 있음을 알 수 있었다. 또한 희박한 분무영역에서는 냉각면에 가공된 휜의 크기와 형상이 분무냉각 열전달에 큰 영향을 미치고 있으나, 분무유량이 증가할수록 이러한 경향은 점차 약해져 본 실험에서 가장 높은 분무유량조건에서는 편평한 냉각면을 제외한 모든 냉각면의 열유속이 거의 동일하게 나타나고 있음을 알 수 있었다.

PRESSURE MODULAION ON MICRO-MACHINED PORT FUEL INJECTOR PERFORMANCE

  • Kim, H.;Im, K.S.;Lai, M.C.
    • International Journal of Automotive Technology
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    • 제5권1호
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    • pp.9-16
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    • 2004
  • An experimental study was carried out to characterize the spray atomization process of micro-machined port fuel injectors with a piezoelectric atomization device, which can generate pressure pulsations through vibration of a piezoelectric transducer. In this study, several types of micro-machined arrays such as 30∼200-microns of hole arrays were tested. Both a dual-stream and a central-port injectors with micro-machined arrays were tested and compared with normal port fuel injectors. The spray visualization was conducted to characterize overall spray structure and phase Doppler particle analyzer (PDPA) system was used to quantify the droplet size and velocity. In addition, the pressure history was recorded by using digitized signal from pressure transducer. The results showed that modulation is effective to the spray atomization for tested injectors and atomization performance depends on injector design factors, orifice sizes, and frequency and power of the modulator. A number of resonance frequencies of the modulator was modified by injector parameters and temperature. In addition, our results suggested that design of sufficient space among holes is critical to avoid droplet coalescence in the multi-hole micro-machined injectors.

탄소 나노튜브 혼합액으로 봉공처리된 텅스텐 카바이드 용사층의 아연 내부식성에 대한 연구 (A study on Zn corrosion resistance of WC spray coating sealed with carbon nanotube suspensions)

  • 김봉훈;이보영
    • Journal of Welding and Joining
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    • 제33권1호
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    • pp.49-53
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    • 2015
  • An experimental study was conducted to investigate the effect of carbon nanotubes on the zinc corrosion resistance of sealing layer formed on the Tungsten Carbide spray coating. Using the nanotubes, a sealing agent in the form of solid-liquid suspensions was made and applied to the surface of spray coating. A series of experiments, consisted of three stages such as preparation of test piece, molten-pot immersion test, and evaluation of micro structure, were undertaken to demonstrate complicated interaction existing between zinc ions and sealing layer containing the nanotubes. Experimental results showed newly developed sealing layer were less susceptible to corrosion and thus coated layer was well protected even in the case of 10 days exposure. Comparison of the micro structure after molten pot test also indicated that carbon nanotubes still remained in the matrix and organized more reliable frame work constituted with boron nitride and chromium compound. It was revealed that carbon nanotubes in the sealing layer played positive role to enhance zinc corrosion resistance in the perspective of both fibrous structure and inherent chemical stability.

가솔린 기관용 인젝터의 분무 구조에 관한 실험적 연구 (An Experimental Study on the Spray Structure of a Gasoline Engine Injector)

  • 조병옥;이창식;임경수
    • 한국자동차공학회논문집
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    • 제3권1호
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    • pp.118-130
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    • 1995
  • Fuel spray in a gasoline engine is a significant factor for the decision of engine power, pollutant emission and the design of intake manifold system. Three kinds of fuel which has other physical properties are chosen in this study, and it is observed using an image processing method that the mechanism and structure of free fuel spray with a throttle type gasoline injector, and the detailed characteristics of droplet size and velocity distributions are obtained by macro and micro-scopic measuring method respectively. It is verified that the initial breakup behaviors are depended on We like the result of Reitz's study, and also observed that the spray of octane and solvent with Re of 210~330 and 270~330 respectively are better than ethanol which has relatively high density and viscosity.

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탄소 나노튜브 알루미늄 복합재료 저온 분사 코팅의 적층 거동 및 특성 (Deposition Behavior and Properties of Carbon Nanotube Aluminum Composite Coatings in Kinetic Spraying Process)

  • 강기철;;이창희
    • Journal of Welding and Joining
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    • 제26권5호
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    • pp.36-42
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    • 2008
  • Carbon nanotube (CNT) aluminum composite coatings were built up through kinetic spraying process. Deposition behavior of CNT aluminum composite on an aluminum 1050 alloy substrate was analyzed based on deposition mechanism of kinetic spraying. The microstructure of CNT aluminum composite coating were observed and analyzed. Also, the electrical resistivity, bond strength and micro-hardness of the CNT aluminum composite coatings were measured and compared to kinetic sprayed aluminum coatings. The CNT aluminum composite coatings have a dense structure with low porosity. Compared to kinetic sprayed aluminum coating, the CNT aluminum composite coatings present lower electrical resistivity and higher micro-hardness due to high electrical conductivity and dispersion hardening effects of CNTs.

박막공정의 융합화를 통한 초소형 고체산화물 연료전지의 제작: I. Spray Pyrolysis법으로 증착된 Ni 기반 음극과 스퍼터링으로 증착된 YSZ 전해질의 다층구조 (Fabrication of Micro Solid Oxide Fuel Cell by Thin Film Processing Hybridization: I. Multilayer Structure of Sputtered YSZ Thin Film Electrolyte and Ni-Based Anodes deposited by Spray Pyrolysis)

  • 손지원;김형철;김혜령;이종호;이해원
    • 한국세라믹학회지
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    • 제44권10호
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    • pp.589-595
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    • 2007
  • Physical properties of sputtered YSZ thin film electrolytes on anode thin film by spray pyrolisis has been investigated to realize the porous electrode and dense electrolyte multilayer structure for micro solid oxide fuel cells. It is shown that for better crystallinity and density, YSZ need to be deposited at an elevated temperature. However, if pure NiO anode was used for high temperature deposition, massive defects such as spalling and delamination were induced due to high thermal expansion mismatch. By changing anode to NiOCGO composite, defects were significantly reduced even at high deposition temperature. Further research on realization of full cells by processing hybridization and cell performance characterization will be performed in near future.

습식 분무 열분해 방법으로 제조한 코발트 도핑된 티타늄 산화막의 표면 및 광학적 특성 (Surface and Optical Characteristics of Cobalt Dopped-titanium Oxide Film Fabricated by Water Spray Pyrolysis Technique)

  • 송호준;박영준
    • 한국재료학회지
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    • 제15권3호
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    • pp.209-215
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    • 2005
  • Titanium dioxide films $(TiO_2)$ doped cobalt transition metal were prepared on titanium metal by water spray pyrolysis technique. Micro-morphology, crystalline structure, chemical composition and binding state of sample groups were evaluated using field emission scanning microscope(FE-SEM), X-ray diffractometer(XRD), Raman spectrometer, X-ray photoelectron spectrometer(XPS). $TiO_2$ films of rutile structure were predominately formed on all sample groups and $Ti_2O_3$ oxide was coexisted on the surface of cobalt doped-sample groups. The optical absorption peaks measured by using UV-VIS-NIR spectrophotometer were observed at specific wavelength region in sample groups doped cobalt ion. This result could be analyzed by introducing crystal field theory.

대형 고속 선박용 러더의 내침식, 부식 특성 향상을 위한 용사 코팅막 (Thermal Spray Coating Layer for Improvement of Erosion and Corrosion Resistance Applicable to Large Sized High Speed Ship's Rudder)

  • 이유송;허성현;김진홍;김여중;배일용;이명훈
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2011년도 춘계학술대회 및 Fine pattern PCB 표면 처리 기술 워크샵
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    • pp.196-197
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    • 2011
  • Rudder, one of the most important component in the marine vessel, is now being decreased life time to serve due to cavitation erosion, vortex current, high flow speed suffer from ship speed going up dramatically. In this study, 10 kinds of thermal spray coating materials(2 of Zn alloy series, 3 of Al alloy series, 3 of Cu alloy series, 2 of STS alloy series) are chosen to apply on specimens and analyze micro structure, metallic composition, properties(porosity, oxidation) by using visual observation, XRD, EDX etc.. Additionally, to refine the characteristic of corrosion endurance for thermal spray coating layer, compared with thermal spray process and 5 kinds of heavy duty painting and AC paint (Anti-Corrosion Paint). Based on above mentioned experimental results, a priority of all coated specimens on corrosion-erosion endurances finalized and summarized there by desirable composition and process of thermal sprayed material properly.

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Effect of Transparency of CNT counter electrodes on the Efficiency of DSSCs

  • Lee, Won-Jae;Ramasamy, Easwaramoorthi;Lee, Dong-Yun;Song, Jae-Sung
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.615-616
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    • 2005
  • Carbon Nanotubes (CNT) on flexible indium tin oxide (ITO) PET films were prepared for dye-sensitized solar cell (DSSC). These CNTs were prepared by spray coating method for various amount of light transparency. Also, Pt counter electrode was prepared by electro deposition method. All $TiO_2$ electrodes were deposited on ITO-PET films by spray coating method. Micro structural images show that CNT counter electrodes prepared by spray-coating have more dense structure with increasing spraying time (0 to 60 seconds). DSSC consisting of $TiO_2$ electrode and CNT counter electrode was fabricated with various amount of light absorption. DSSC have higher light energy conversion efficiency with increasing the thickness of CNT counter electrode. CNT counter electrode is at least compatible to that of CNT counter electrode.

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