• 제목/요약/키워드: Fiber-reinforced Composite

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Friction Bushing용 복합재료의 미끄럼 마찰마모특성에 관한 연구 (Sliding Wear and Friction Properties of Composite Materials for Friction Bushing)

  • 이한영;허대홍;김태준;조용재;조범래;허만대
    • Tribology and Lubricants
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    • 제22권1호
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    • pp.1-7
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    • 2006
  • The sliding friction and wear properties of mineral fiber reinforced composite(MF) and glass fiber reinforced composites(GF) are investigated to clarify their field of use and the role of each fiber in friction material. Friction and wear test reveals that GF composite has better wear resistance even though with low friction coefficient, comparing with MF composite. Glass fiber strengthen effectively the matrix and may absorb friction energy to convert it into the fracture energy of them, as well as its lubricative role. However, mineral fiber in MF composite is too small to strengthen the matrix. Then MF composite are easily plowed and worn out by asperity on counter material. Friction coefficient of MF composite is higher friction coefficient than that of GF composite and varied widely with test.

섬유 보강 복합레진의 섬유 방향이 중합수축에 미치는 영향 (EFFECT OF FIBER DIRECTION ON THE POLYMERIZATION SHRINKAGE OF FIBER-REINFORCED COMPOSITES)

  • 염중원;이인복
    • Restorative Dentistry and Endodontics
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    • 제34권4호
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    • pp.364-370
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    • 2009
  • 본 연구의 목적은 strain gage와 LVDT (linear variable differential transformer) 변위센서를 이용하여 섬유 보강 복합레진에서 섬유의 방향이 복합레진의 중합수축에 미치는 영향을 알아보기 위함이다. 지름 10 mm, 높이 2 mm의 원반 모양 유동성 복합레진 (Aeliteflo A2, Bisco, Inc., IL, USA) 중앙에 유리섬유 (X-80821P Glass Fiber, Bisco, Inc., IL, USA)를 위치시키고, 섬유가 배열된 장축 방향 (longitudinal)과 수직방향 (transversal)의 중합수축량을 strain gage (Linear S-series 350${\Omega}$, CAS, Seoul, Korea)를 이용하여 각각 측정하였다. 사용된 유동성 복합레진 자체의 free 중합수축을 구하기 위해 지름 7 mm, 높이 1 mm의 원반 모양 시편의 수직 방향 (axial) free 중합수축값을 LVDT로 측정하였다. 중합된 시편들을 절단하여 주사전자현미경으로 복합 레진 내부의 섬유배열을 관찰하고 각 군에서 측정된 평균 수축값들을 ANOVA로 비교하였고 Scheffe post-hoc test로 사후 검정하였다 (${\alpha}$=0.05). 섬유가 배열된 평면 상에서 복합레진의 중합수축 (radial shrinkage)은 섬유와 평행한 방향에서 감소하고 섬유와 수직한 방향에서 증가했다 (p<0.05). 본 연구의 결과 섬유 보강 복합레진으로 스플린트나 수복물을 제작할 때 중합수축량은 보강된 섬유의 배열방향에 따라 큰 차이가 남을 알 수 있었다.

섬유강화 복합재료의 비접촉식 초음파 평가 기법 연구 (A Study of Non-contacting Ultrasonic Technique for Evaluation of Fiber Reinforced Composite Materials)

  • 최상우;서경철;이준현;변준형
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2004년도 추계학술발표대회 논문집
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    • pp.268-271
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    • 2004
  • Non-contact technique should be developed for receiving ultrasonic wave for on-line monitoring of processing defects of fiber reinforced composites, since couplant must be applied on composite materials when conventional ultrasonic testing technique was used. Restriction of conventional ultrasonic testing technique was proven by transmitting and receiving ultrasonic wave on CFRP in various direction of wave propagation with various incident angle of ultrasonic beam. Air-coupled transducer and laser interferometer were applied for non-contacting reception of ultrasonic wave in fiber reinforced composite materials. Air-coupled transducer has optimal sensitivity and frequency band of 300kHz has homogeneous characteristics on direction of wave propagation.

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왕겨분말 복합재료의 기계적 특성에 미치는 제조인자의 영향 (Effect of Manufacturing Factors on Mechanical Properties of the Rice-husk Powder Composites)

  • 최준용;;윤호철;임재규
    • 대한기계학회논문집A
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    • 제30권7호
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    • pp.794-799
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    • 2006
  • In recent years, the use of natural fiber as reinforcement in polymer composites to replace synthetic fiber such as glass fiber is receiving increasing attention. Because of increasing usage according to the high demand, the cost of thermoplastic has increased rapidly over the past decades. We used a thermoplastic polymer(polypropylene) as the matrix and a lignocellulosic material(rice-husk flour) as the reinforcement filler to prepare a particle-reinforced composite to examine the possibility of using lignocellulosic material as reinforcement filler and to determine data of test results for physical, mechanical and morphological properties of the composite according to the reinforcement filler content in respect to thermoplastic polymer, In this study, PLA/PP rice-husk fiber-reinforced thermoplastic composites that made by the hot press molding method according to appropriate manufacturing process was evaluated as mechanical properties.

충격하중을 받는 섬유보강 콘크리트 및 시멘트 복합체의 배면변형특성 (Strain Properties on Rear Side of Fiber Reinforced Concrete and Cement Composite by Impact Load)

  • 이상규;김규용;이보경;윤민호;손민재;김경태
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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    • pp.158-159
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    • 2017
  • In this study, it evaluate the strain properties of fiber reinforced concrete and fiber reinforced cement composite. The types of fiber are Hooked steel fiber and it was mixed 0.5, 1.0 vol.% in concrete and 1.0, 2.0 vol.% in cement composites. The impact test was conducted by using a projectile (diameter: 25mm, velocity: 170m/s) and strain properties on the rear side of each specimen was evaluated by strain gage. After the impact test, fracture grade, fracture depth was evaluated.

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합성섬유 종류가 무시멘트 복합재료의 재료 거동에 미치는 영향 (Effects of Type of Synthetic Fiber on Material Properties of Cementless Composite)

  • 최정일;박세언;차상률;이방연
    • 한국건설순환자원학회논문집
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    • 제7권3호
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    • pp.255-261
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    • 2019
  • 이 연구의 목적은 보강섬유로 합성섬유의 종류가 알칼리활성 슬래그 복합재료의 역학성능에 미치는 영향을 조사하는 것이다. 이를 위하여 매트릭스 재료 및 배합을 결정하였고, 폴리프로필렌, 폴리비닐알코올, 폴리에틸렌 섬유로 보강된 복합재료의 압축강도, 인장성능 및 균열패턴을 평가하였다. 실험결과 폴리비닐알코올 섬유와 폴리에틸렌 섬유로 보강한 복합재료는 유사한 인장성능을 나타낸 반면 폴리프로필렌 섬유로 보강한 복합재료는 낮은 인장성능을 나타내었다. 또한 동일한 매트릭스이더라도 섬유의 종류에 따라 인장거동에 큰 차이가 발생하는 것을 확인하였으며, 섬유의 강도나 형상비 이외의 요인들도 인장거동에 큰 영향을 미치는 것을 확인하였다.

횡방향 하중을 받는 금속모재 복합재료의 파손구조 (Failure Mechanism of Metal Matrix Composites Subject to Transverse Loading)

  • 함종호;이형일;조종두
    • 대한기계학회논문집A
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    • 제24권6호
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    • pp.1456-1469
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    • 2000
  • Mechanical behaviors of uniaxially fiber-reinforced metal matrix composites under transverse loading conditions were studied at room and elevated temperatures. A mono-filament composite was selecte d as a representative analysis model with perfectly bonded fiber/matrix interface assumption. The elastic-plastic and visco-plastic models were investigated by both theoretical and numerical methods. The product of triaxiality factor and effective strain as well as stress components and strain energy was obtained as a function of location to estimate the failure sites in fiber-reinforced metal matrix composite. Results showed that fiber/ matrix interfacial debond plays a key role for local failure at the room temperature, while void creation and growth in addition to the interfacial debond are major concerns at the elevated temperature. It was also shown that there would be an optimal diameter of fiber for the strong fiber-reinforced metal matrix composite.

홍조류 섬유를 보강재로 사용한 바이오복합재료의 특성 (Use and advantage of Red algae fiber as reinforcement of Biocomposite)

  • 이민우;서영범;한성옥
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2007년도 추계학술발표논문집
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    • pp.93-102
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    • 2007
  • Biocomposite was organized with biodegradable polymer and natural fiber that has potential to be used as replacement for glass fiber reinforced polymer composite with the benefits of low cost, low density, acceptable specific strength, biodegradability, etc. Until now, non-wood fibers have been used as reinforcements of biocomposite which are all plant-based fibers. The present study focused on investigating the fabrication and characterization of biocomposite reinforced with red algae fiber. The bleached red algae fiber(BRAF) showed very similar crystallinity to the cellulose. It has high stability against thermal degradation (maximum thermal decomposition temperature of 359.3$^{\circ}C$) and thermal expansion. Biocomposites reinforced with BRAF have been fabricated by a compression molding method and their mechanical and thermal properties have been studied. The storage modulus and the thermomechanical stability of PBS matrix are markedly improved with reinforcing the BRAF. These results support that the red algae fiber can be used as an excellent reinforcement of biocomposites as "green-composite" or "eco-composite".

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