• 제목/요약/키워드: 직조

검색결과 178건 처리시간 0.026초

직조 탄소섬유 발포 고분자 샌드위치 구조의 굽힘특성 (Bending Characteristics of Carbon Fabric/Polymeric Foam for Sandwich Structures)

  • 장승환;장태성;최진호;전성식
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2004년도 추계학술발표대회 논문집
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    • pp.131-134
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    • 2004
  • In this paper, a representative unit volume (RUV) model was employed to simulate thermoforming process of carbon fabric-polymeric foam sandwich structures. Thermoforming simulations, which capture crimp angles and amplitude changes of carbon fabric with respect to different types of foams under the operating pressure were conducted with the help of RUV model. Changed shapes of tow structure after thermoforming were reflected in the two dimensional to determine mechanical properties of skin parts, i.e_ carbon fabric composites after thermoforming. Bending simulations with respect to different foam systems as well as different moduli of carbon fabric composites were successfully carried out by using properties obtained from two-dimensional analyses.

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극저온 환경에서 탄소섬유강화 직조/일방향 복합재료의 인장 물성 측정 (Tensile Properties of CERP Fabric/Unidirectional Composites under Cryogenic Environment)

  • 김명곤;김철웅;강상국;김천곤;홍창선
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2003년도 추계학술발표대회 논문집
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    • pp.115-118
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    • 2003
  • This research aims to measure mechanical tensile properties of CFRP composites for cryogenic tank material. Through the cryogenic chamber, tensile tests are peformed under cryogenic temperature for graphite/epoxy fabric specimen aged at $-150^{\circ}C$ for 30hrs with load and graphite/epoxy unidirectional specimen 3-cycled from RT to $-100^{\circ}C$ with load. For graphite/epoxy fabric specimen, tensile modulus showed to increase after aging at cryogenic temperature(CT) while to decrease after aging at room temperature(RT) and tensile strength is more decreased after CT-aged than at RT-aged. For graphite/epoxy unidirectional specimen, tensile modulus was almost not changed after 3-cycling but strength showed the trend of decrease as increase the number of cycling.

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2D 및 3D 직조형 복합재료의 충격특성 (Impact Properties of 2D and 3D Textile Composites)

  • 변준형;엄문광;황병선;송승욱;강형
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2003년도 추계학술발표대회 논문집
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    • pp.91-94
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    • 2003
  • Laminated composites are liable to fatal damage under impact load due to the fact that they have no reinforcement in the thickness direction. To overcome the inherent weakness, three dimensional (3D) textile reinforcements have drawn much interests. In this paper, impact performance of 2D and 3D textile composites has been characterized. For 2D composites, fiber bundle size and fiber pattern have been varied. For 3D composites, orthogonal woven preforms of different density and type of through-thickness fibers have been studied. To assess the damage after the impact loading, specimens were subjected to C-scan nondestuctive inspection. Compression after impact (CAI) were also conducted in order to evaluate residual compressive strength.

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직조된 대나무 자연섬유 복합재료의 제조인자에 따른 굽힘강도 (Bending Strength of Natural Woven Bamboo Fiber-reinforced Polymer Composites with Manufacturing Factors)

  • 송준희;임재규
    • 대한기계학회논문집A
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    • 제30권8호
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    • pp.916-922
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    • 2006
  • In recent years there has been a growing interest for the use of natural fibers in composite applications due to their low cost, environmental friendliness, and good mechanical properties. The purpose of this study is to determine the characteristic of bending strength on bamboo fiber reinforced polymer composites. The parameters of RTM process depend on the weight ratio of bamboo fiber and resin, the number of bamboo ply and amount of hardening agent. Mechanical properties was investigated for each process factor of polymer composites. Test result shows that bending strength was a maximum(approximately 85MPa) value when composite thickness was 6mm and weight ratio of resin was 13%.

퍼스날 컴퓨터에 의한 dobby 직물의 직조무늬 디자연 (Personal Computer Aided Design for Patterns of Dobby Woven Fabrics)

  • 안동문;양철곤
    • 한국의류학회지
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    • 제9권2호
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    • pp.85-97
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    • 1985
  • The purpose of this study is to develop a new method for the visual presentation of weaves and woven patterns of dobby fabrics by using the personal computer briefly. The following results were given through adapting this method to the design for patterns of woven fabrics. 1. Complete weaves were given by computerizing the pegging plan and drafting system. 2. The effect of the combined woven patterns were given by computerizing the one complete weaves, the differently coloured warp threads, and the differently coloured weft threads.

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볼록형 와이어 직조 카고메 트러스 PCM의 압축특성평가 (The Compressive Characteristics of The Convex Type Wire-woven Bulk Kagome Truss PCM)

  • 이명진;강기주
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.138-143
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    • 2008
  • Recently, a new periodic cellular metal(PCM) named as Wire wove Bulk Kagome(WBK) was introduced. Based on the shape of tetrahedra composing a WBK, WBKs are classified into two types, namely, concave and convex type. They are easily differentiated by changing the assembling sequence. The effect of geometrical parameters such as the wire diameter, strut length and number of layers on the compressive behavior of concave type WBK has already been investigated. In this work, the similar works were performed with the convex type WBKs. It was shown that the compressive strength of the convex type WBK was quite similar to that of the concave type. The compressive strengths of convex type specimens also depend on the slenderness ratio, but a little different from those of concave type specimens in the detailed behavior. And densification occurs earlier than the concave type WBK.

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고속전철 내장부품용 유리섬유 직조 페놀수지 복합재료 적층판의 인장-인장 피로특성 및 인장-인장 베어링 피로특성 (Tension-Tension Fatigue and Tension-Tension Bearing Fatigue Characteristics of Glass Fabric/Phenol Composite Laminates for the Internal Components of the High Speed Trains)

  • 김진봉;황병선;이상관;박지상;조정미
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2002년도 추계학술대회 논문집(II)
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    • pp.904-909
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    • 2002
  • This paper contains the tension-tension and the tension-tension bearing fatigue characteristics of glass fabric/phenol composite laminates. The experimental results show that the bearing fatigue characteristics of the material is so excellent compared with the simple tension fatigue characteristics, that there are no needs of additional strengthening for mechanical joint parts when the parts are properly designed. The experimental data are also compared with the results of glass fabric/epoxy composite laminates.

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유한요소해석을 이용한 직조 탄소섬유 발포 고분자 샌드위치 구조의 압축특성 (FE Analyses of the Compressive Characteristics of Carbon Fabric/Polymeric Foam for Sandwich Structure)

  • 장승환;전성식
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2004년도 춘계학술발표대회 논문집
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    • pp.194-197
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    • 2004
  • In this paper, compressive characteristics of carbon fabric skin with polymeric foam core sandwich structure were investigated by FE analyses and compressive tests of polyurethane foam were also conducted with respect to temperature changes, which were determined by curing processes of epoxy or polyester resin to obtain mechanical behaviour of polyurethane foam. FE analyses indicated variation of parameters with respect to manufacturing pressure, which have comparatively massive effect upon mechanical properties of sandwich structures, i.e. wavelength as well as crimp angle of carbon fabric

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