• 제목/요약/키워드: Composite Material

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Hybrid Vibration Control of Smart Laminated Composite Beams using Piezoelectric and Viscoelastic Material

  • Kang, Young-Kyu
    • International Journal of Precision Engineering and Manufacturing
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    • 제4권1호
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    • pp.37-42
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    • 2003
  • Active control of flexural vibrations of smart laminated composite beams has been carried out using piezoceramic sensor/actuator and viscoelastic material. The beams with passive constrained layer damping have been analyzed by formulating the equations of motion through the use of extended Hamilton's principle. The dynamic characteristics such as damping ratio and modal damping of the beam are calculated for various fiber orientations by means of iterative complex eigensolution method. This paper addresses a design strategy of laminated composite under flexural vibrations to design structure with maximum possible damping capacity.

삼차원 평판형태 브레이딩 복합재료의 강성해석 (The mechanical analysis of 3-D flat board shaped braided composites)

  • 김성준;강태진;정관수;윤재륜
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2002년도 추계학술발표대회 논문집
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    • pp.114-117
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    • 2002
  • To develop an effective geometric modeling is essential in order that precise material properties of the 3-D braided composite can be estimated. in this study RVE(representative volume element) which is the smallest volume element representing whole material properties is developed to estimate the mechanical properties of 3-D flat board shaped braided composite using volume averaging method.

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송배전용 COMPOSITE INSULATOR의 SHED 재질로서 실리콘 고무 (Silicone Rubber as the Shed Material of Composite Insulator for Electric Power Distribution and Transmission)

  • 강동필
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 하계학술대회 논문집 C
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    • pp.1367-1369
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    • 1994
  • Recently composite insulators have been In the spotlight because they have many good characteristics as a outdoor insulator for high voltage. The long term properties in composite insulator depend on shed materials. Silicone rubber out of some candidates of shed material has been obtaining good credit from the long term test in field.

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에폭시 복합체의 실리콘유중 연면파괴에 관한 연구 (A Study on The Surface Breakdown of Epoxy Composite in Silicon Oil)

  • 장인범;정인재;정일형;유재웅;오재한;김종헌;이준웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.195-198
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    • 1998
  • In this paper, we study on the surface breakdown of Epoxy composite in silicon oil. Breakdown field strengths were simulated by using FEM with the experience data of surface breakdown of Epoxy composite. The surface endurance and field distribution (kV/mm) of Epoxy composite were calculated by FEM.

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보강된 복합재료 쉘구조물에 대한 좌굴후 해석모듈의 특성분석 (Characteristic analysis for postbuckling analysis modules of stiffened composites shell structure)

  • 오세희;김천곤;김광수
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2004년도 춘계학술발표대회 논문집
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    • pp.288-291
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    • 2004
  • The characteristics of the buckling analysis module for stiffened composite structures were studied in this paper. Composite stiffened structures have geometrical asymmetry and material properties asymmetry. Due to these reason, postbuckling analysis was essential and the characteristics of postbuckling analysis modules for ABAQUS were researched. Static analysis module was considered. By considering the material nonlinearity, progressive failure mechanism was applied and buckling strength was estimated

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탄소성이론을 이용한 복합지반의 대표 강도정수 예측 (Determination of Composite Strength Parameter Using Elasto-Plastic Theory)

  • 이주형;김영욱;박용원
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 봄 학술발표회 논문집
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    • pp.93-100
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    • 2002
  • Vertical reinforcement of soft soils using the deep mixing method has received increasing applications. In this study, the theory of elasticity and plasticity including the upper bound theorem of limit analysis were used to derive the equations for obtaining composite elastic properties and shear strength parameters. The developed equations were validated using the finite element computer program SAGE CRISP. The analysis involved 4 different cases-two different type of soil and replacement ratios. Tile results of the analysis show that the proposed equations could determine the properties of composite material for practical applications.

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Composite 부싱의 기밀 특성을 위한 최적의 압착에 관한 연구 (A Study on Optimal Fitting for Tightness Characteristics of Composite Bushing)

  • 조한구;강형경;유대훈
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 하계학술대회 논문집
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    • pp.390-391
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    • 2009
  • Recently, composite hollow bushings have been increasingly employed mainly from the various characteristics. Composite bushings are superior to porcelain bushings in several respects, including lighter weight, better anti-pollution and anti-explosion properties, and easer manufacturing. This paper deals with the optimal thermal fitting for improved tightness characteristics of composite bushing. Two types of composite bushings were fabricated. For optimal fitting process, it is necessary using adhesive and designed internal structure of flange and FRP tube. In this study, for improved tightness characteristics of composite bushing has prominence and interface tolerance of flange and FRP tube. From FE-SEM analysis the adhesive layers were different with interface tolerance, sample 1 and 2 which have respective about $120{\mu}m$ and $50{\mu}m$.

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복합재료 원통쉘의 진동, 좌굴강도, 충격강도 특성 및 그의 설계최적화에 관한 연구 (A Study on the Design Optimization of Composite cylindrical shells with Vibration, Buckling Strength and Impact Strength Characteristics)

  • 이영신;전병희;오재문
    • 한국자동차공학회논문집
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    • 제5권4호
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    • pp.48-69
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    • 1997
  • The use of advanced composite materials in many engineering structures has steadily increased during the last decade. Advanced composite materials allow the design engineer to tailor the directional stiffness and the strength of materials as required for the structures. Design variables to the design engineer include multiple material systems. ply orientation, ply thickness, stacking sequence and boundary conditions, in addition to overall structural design parameters. Since the vibration and impact strength of composite cylindrical shell is an important consideration for composite structures design, the reliable prediction method and design methodology should be required. In this study, the optimum design of composite cylindrical shell for maximum natural frequency, buckling strength and impact strength are developed by analytic and numerical method. The effect of parameters such as the various composite material orthotropic properties (CFRP, GFRP, KFRP, Al-CFRP hybrid), the stacking sequences, the shell thickness, and the boundary conditions on structural characteristics are studied extensively.

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세라믹 분말 크기가 압전 세라믹-폴리머 복합체의 유전 및 압전 특성에 미치는 영향 (Dielectric and Piezoelectric of Ceramic-Polymer Composite with Ceramic Particle Size)

  • 이형규;김호기
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1989년도 춘계학술대회 논문집
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    • pp.63-65
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    • 1989
  • Piezoelectric BaTiO$_3$-polymer composite were investigated for dielectric and piezoelectric properties with the barium titanate active particle size. Under the condition of the same density and ceramic volume ratio of composite, the dielectric and piezoelectric constant of composite are increasing as the ceramic particle size in composite are increasing. The surface layer model was quoted to explain these phenomena in our system and experimentally confirmed. The connectivity parameter of modified cube model of composite was calculated from the dielectric constant variation as their particle size. The connectivity parameter X and Y were 77.8% and 98.9% respectively. It means that the barium titanate particle distribution in composite nearly approach to the parallel mode. It was experimentally confirmed that the surface layer has low dielectric and nonferroelectric properties. Dielectric constant and thickness of surface layer were calculated from the equivalent circuit of composite.

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