• 제목/요약/키워드: bond resistance

검색결과 401건 처리시간 0.028초

단체량 및 이량체액정에서 나타나는 Carbonate 결합기의 열역학적거동 (Thermodynamic Behaviors of Carbonate Linking Group in Monomer and Dimer Liquid Crystals)

  • 남수용
    • 한국인쇄학회지
    • /
    • 제13권1호
    • /
    • pp.13-24
    • /
    • 1995
  • The color filter os made in four methods ; dyeing, printing electrodisposition and pigment dispersed method. Among technologies for color filter manufacture, pigment-dispersed and hybrid method are dominant over all others in commercial manufacture of large scale, fine resolution color filter for liquid crystal display. In this paper to investigate the possibility of the color filter manufacture for LCD by screen printing method, we synthesyzed PVA/sbQ screen emulation for high resolution, estimated image of printed fine pattern and manufactured color filter by screen printing. Results of the study are as follow and found the screen printing method os useful and valid from it. 1. Fine pattern is formed due to photocyclodomerization of -C=C- bond at 342nm, on the other hand unexposured parts are removed in water. 2. sharpness and resolution of fine pattern is improved at mesh streching angle 22.5 and 45 than 0 degree. It is expected due to resistance between inks and mesh streching angles. 3. Spectral characteristics of sample inks were R(640nm), G(535nm), B(470nm), transmittance were R(92%), G(79%), B(70%) and chromaticity coordinate values were R(0.62,0.33), G(0.32,0.59), B(0.14,0.17)

  • PDF

Evaluation on the Mechanical Performance of Low-Quality Recycled Aggregate Through Interface Enhancement Between Cement Matrix and Coarse Aggregate by Surface Modification Technology

  • Choi, Heesup;Choi, Hyeonggil;Lim, Myungkwan;Inoue, Masumi;Kitagaki, Ryoma;Noguchi, Takafumi
    • International Journal of Concrete Structures and Materials
    • /
    • 제10권1호
    • /
    • pp.87-97
    • /
    • 2016
  • In this study, a quantitative review was performed on the mechanical performance, permeation resistance of concrete, and durability of surface-modified coarse aggregates (SMCA) produced using low-quality recycled coarse aggregates, the surface of which was modified using a fine inorganic powder. The shear bond strength was first measured experimentally and the interface between the SMCA and the cement matrix was observed with field-emission scanning electron microscopy. The results showed that a reinforcement of the interfacial transition zone (ITZ), a weak part of the concrete, by coating the surface of the original coarse aggregate with surface-modification material, can help suppress the occurrence of microcracks and improve the mechanical performance of the aggregate. Also, the use of low-quality recycled coarse aggregates, the surfaces of which were modified using inorganic materials, resulted in improved strength, permeability, and durability of concrete. These results are thought to be due to the enhanced adhesion between the recycled coarse aggregates and the cement matrix, which resulted from the improved ITZ in the interface between a coarse aggregate and the cement matrix.

Nano-Scale Cu Direct Bonding Technology Using Ultra-High Density, Fine Size Cu Nano-Pillar (CNP) for Exascale 2.5D/3D Integrated System

  • Lee, Kang-Wook
    • 마이크로전자및패키징학회지
    • /
    • 제23권4호
    • /
    • pp.69-77
    • /
    • 2016
  • We propose nano-scale Cu direct bonding technology using ultra-high density Cu nano-pillar (CNP) with for high stacking yield exascale 2.5D/3D integration. We clarified the joining mechanism of nano-scale Cu direct bonding using CNP. Nano-scale Cu pillar easily bond with Cu electrode by re-crystallization of CNP due to the solid phase diffusion and by morphology change of CNP to minimize interfacial energy at relatively lower temperature and pressure compared to conventional micro-scale Cu direct bonding. We confirmed for the first time that 4.3 million electrodes per die are successfully connected in series with the joining yield of 100%. The joining resistance of CNP bundle with $80{\mu}m$ height is around 30 m for each pair of $10{\mu}m$ dia. electrode. Capacitance value of CNP bundle with $3{\mu}m$ length and $80{\mu}m$ height is around 0.6fF. Eye-diagram pattern shows no degradation even at 10Gbps data rate after the lamination of anisotropic conductive film.

이온주입에 의한 폴리머의 전기특성 조사 (Electrical properties of polymers by ion implantation)

  • 양대정;김보영;이재형
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
    • /
    • pp.203-207
    • /
    • 2003
  • Ion implantation has been shown to significantly alter the surface properties of polymers. Polycarbonate(PC) and Polyimide(PI) were irradiated with 50keV $N^+$, $Xe^+$ ions to the fluences of $1{\times}10^{16}{\sim}3{\times}10^{17}\;cm^2$. The ion beam-induced modification of the electrical conductivity and the related structural features have been studied for polymers. The beam-induced chemical and structural modifications have been investigated by using X-ray Phooelectron Spectroscopy(XPS) and Fourier Transform-Infrared Spectroscopy(FT-IR), while the modification of the electrical properties was followed by performing a complete set of sheet resistance measurements. Samples irradiated at higher fluence showed a good conductivity, with a saturation value of $10^7{\Omega}/sq$. The XPS data demonstrate that the modification of the electrical properties is due to the progressive formation with increasing ion fluence of a dense amorphous carbon network, while PF-IR data reveal that material degradations through bond breaking are the main effects.

  • PDF

WS2 윤활제를 첨가한 마이크로 다이아몬드 블레이드의 절삭성능과 기계적 특성 (Cutting Efficiency and Mechanical Characteristics of Diamond Micro-blades Containing WS2 Lubricant)

  • 김송희;장재철
    • 한국표면공학회지
    • /
    • 제45권1호
    • /
    • pp.37-42
    • /
    • 2012
  • $WS_2$ powder was added to the Cu/Sn bond metal of diamond micro-blades for machining of semi-conductor and IC chips to improve cutting efficiency. The effect of $WS_2$ additive on cutting efficiency was investigated and compared with the micro-blades with $MoS_2$ developed in previous research. Flexural strength, frictional coefficient, and wear resistance of blades decreased with $WS_2$ but wear depth increased. It was found that the blades including $WS_2$ consumed less momentary energy than the blades containing $MoS_2$ during dicing test. Micro-blades containing $WS_2$ exhibited lower flexural strength than the blades with $MoS_2$ resulting from higher amount of sintering defects relevant to the less effectiveness of $WS_2$ on fluidity. The effect of $WS_2$ and $MoS_2$ on fluidity during sintering was analyzed in terms of mismatching degree between the longitudinal direction of lubricant particles and the perpendicular direction to the compact loading. The blade with 8.1 vol.% of $WS_2$ showed the best cutting efficiency.

인장을 받는 고강도철근콘크리트 부재의 정착성능 평가 (Development Properties of Rebar in Tension with High Strength Concrete)

  • 박수희;이범식;김상연;박성식;배기선;김성덕
    • 토지주택연구
    • /
    • 제2권1호
    • /
    • pp.53-60
    • /
    • 2011
  • 인장을 받는 고강도콘크리트 부재의 정착특성을 평가하고 KCI 2007 정착길이 산정기준의 적용가능성을 평가하기 위하여 콘크리트강도와 정착길이, 섬유혼입률을 변수로 한 정착실험을 수행하였다. 정착실험 수행 결과, 인장을 받는 80MPa의 고강도콘크리트 부재에서 KCI 2007의 최소정착길이의 적용이 가능할 것으로 기대된다. 고강도콘크리트의 내화성능을 확보하기 위하여 혼입되는 섬유(NY+PP)는 0.1%까지 혼입하여도 고강도콘크리트의 정착특성에 영향을 미치지 않는 것으로 나타났다.

강섬유콘크리트의 직접인장 거동 특성 (Direct Tensile Behavior of Steel.Fiber Reinforced Concrete)

  • 이신호;고재군
    • 한국농공학회지
    • /
    • 제29권4호
    • /
    • pp.124-131
    • /
    • 1987
  • The aims of this study was to determine the mechanical properties of steel-fiber reinforced concrete under direct tensile loading, and also to insestigate the mechanism fiber reinforcement in order to improve the possible applications of steel-fiber reinforced concrete. In this study the major variables of experimental investigation were fiber conntents, and the lengths and diameters of fibers. The major results obtained are summarized as follows : 1. The strength, elastic modulus and energy absorption capability of steel-fiber reinforced concrete under direct tensile loading were improved as increasing of fiber contents. 2. The direct tensile strength of steel-fiber reinforced concrete was not influenced by the lengths of fiber, but was decreased as increasing of fiber diameters. 3. The direct tensile strength of steel-fiber reinforced concrete was not influenced by the fiber aspect-ratio, but this was because the fiber contents were below the critical value of fiber content. 4. The correlation of direct tensile strength and combined parameter, Vf l/d, was not good. 5. Mutiple cracking and post-crack resistance were investigated at stress-strain curves in direct tensile test. 6. The effect of fiber reinforcement can be influenced by fiber orientation and the bond strength between fiber and matrix. 7. The improvement of mechanical properties of steel-fiber reinforced concrete under direct tensile loading can be theoretically explained by the concept of composite materials.

  • PDF

섬유상 여과필터의 고온 내구성 향상을 위한 테프론 코팅 연구 (Teflon coating of fabric filters for enhancement of high temperature durability)

  • 김은주;박영구
    • 한국응용과학기술학회지
    • /
    • 제28권2호
    • /
    • pp.232-239
    • /
    • 2011
  • Fabric fibrous filter has been used in various industrial applications owing to the low cost and wide generality. However, the basic properties of fabric materials often limit the practical utilization including hot gas cleaning. This study attempts to find new coatings of porous fibrous filter media in order to overcome its insufficient thermal resistance and durability. Teflon was one of the plausible chemicals to supplement the vulnerability against frequent external thermal impacts. A foaming agent composed of Teflon and some organic additives was tentatively coated on the glass fiber mat. The present test Teflon foam coated filter was fount to be useful for hot gas cleaning, up to $250^{\circ}C$-$300^{\circ}C$. Close examination using XPS(X-ray Photoelectron Spectroscopy) and Contact angle proved the binding interactions between carbon and fluorine, which implies coating stability. The PTFE/Glass foam coated filter consisted of more than 95% (C-F)n bond, and showed super-hydrophobic with good-oleophobic characteristics. The contact angle of liquid droplets on the filter surface enabled to find the filter wet-ability against liquid water or oil.

구조용 합성섬유의 최적형상함수 결정 (Optimum Geometry Factor of Structural Synthetic Fibers)

  • 원종필;임동휘;박찬기;한일영;김방래
    • 콘크리트학회논문집
    • /
    • 제14권4호
    • /
    • pp.474-482
    • /
    • 2002
  • 본 연구의 목적은 섬유의 부착시험을 통하여 섬유의 파괴없이 최대 인발저항을 가지고 시멘트 모체 내에서 완전한 정착작용을하는 구조용 합성섬유의 최적형상과 최적형상함수를 도출하는데 있다. 7가지 다른 형상의 구조용 합성섬유를 조사하였고 부착시험을 수행하였다. 부착시험의 변수는 7가지의 다른 형상이고, 2종류의 시멘트 모르타르의 배합이다. 부착시험 결과, 7가지 다른 형상중 crimped type이 계면인성(인발에너지)와 인발하중에서 가장 우수한 성능을 보였다. Crimped type을 기본으로 하여 섬유의 주기와 높이를 바꾸어 부착시험을 실시한 결과 최적형상함수, D= $b^{{\alpha}ο{\alpha}}$ $h^{λ{\beta}}$ 를 도출하였다.

장스팬 슬라브 콘크리트의 열화저감에 대한 연구 (A Study on Reducing Deterioration in Long-span Slab Concrete)

  • 김대건;차훈;최상환;문경식
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2014년도 추계 학술논문 발표대회
    • /
    • pp.11-12
    • /
    • 2014
  • In this study, fundamental properties of concrete mixed with fiber has been analysed. Compressive strength, tensile strength and plastic shrinkage has been tested to conduct the optimum addition ratio of fiber. Effect to control press concrete's cracking has been tested. The following results could be made as the conclusion. For the flowability, slump decreased about 41-79% when all types of fiber used in the concrete. When the addition ratio of fiber is 1.2%, the slump of concrete decreased about 45%. For the strength properties. all the specimens with different addition ratio of fiber shown higher compressive strength comparing with Plain. Comparing with Plain, cracking decreased when the fiber added. Especially, when NY fiber used in the concrete, the plastic shrinkage did not occurred. In addition, Latex modified concrete(LMC) has improved superior physical and chemical properties. The properties of latex, combined with the low water-cement ratio, produce a concrete that has improved flexural, tensile, and bond strength, lower modulus of elasticity, increased freeze-thaw resistance, and reduced permeability compared to conventional concrete of similar mix design.

  • PDF