• Title/Summary/Keyword: 탄소 단섬유

Search Result 25, Processing Time 0.029 seconds

Study of Manufacturing Process and Properties of C/C Composites with Recycled Carbon Fiber Reinforced Plastics (리싸이클 CFRP 적용 C/C 복합재료 제조 및 특성 연구)

  • Kim, Seyoung;Han, In Sub;Bang, Hyung Joon;Kim, Soo-hyun;Seong, Young-Hoon;Lee, Seul Hee
    • Composites Research
    • /
    • v.35 no.4
    • /
    • pp.242-247
    • /
    • 2022
  • This study has a different direction from the existing technology of applying recycled carbon fiber obtained by recycling waste CFRP to CFRP again. A study was conducted to utilize recycled carbon fiber as a raw material for manufacturing a carbon/carbon (C/C) composite material comprising carbon as a matrix. First, it was attempted to recycle a commonly used epoxy resin composite material through a thermal decomposition process. By applying the newly proposed oxidation-inert atmosphere conversion technology to the pyrolysis process, the residual carbon rate of 1~2% was improved to 19%. Through this, the possibility of manufacturing C/C composite materials utilizing epoxy resin was confirmed. However, in the case of carbon obtained by the oxidation-inert atmosphere controlled pyrolysis process, the degree of oxygen bonding is high, so further improvement studies are needed. In addition, short-fiber C/C composite material specimens were prepared through the crushing and disintegrating processes after thermal decomposition of waste CFRP, and the optimum process conditions were derived through the evaluation of mechanical properties.

Abrasive Wear of Hybrid Metal Matrix Composites for High Wear Resistance (고 내마모성 혼합 금속복합재료의 연삭마모)

  • 송정일
    • Composites Research
    • /
    • v.12 no.5
    • /
    • pp.12-22
    • /
    • 1999
  • Aluminum based metal matrix composites(MMCs) are well known for their high specific strength, stiffness and hardness. They are gaining further importance because of their high wear resistance. In this study wear behavior of $Al/Al_2O_3/C$ hybrid MMCs fabricated by squeeze infiltration method was characterized by the abrasive wear test under various sliding speeds at room and high temperature. Wear resistance of MMCs was improved due to the presence of reinforcements at high sliding speed. Especially wear resistance of carbon hybrid MMCs was superior to other materials because of its solid lubrication of carbon. The friction coefficient of MMCs was not affected by the sliding speed.

  • PDF

Investigation of Interfacial Adhesion of Different Shapes of Nano Carbon Fillers Reinforced Glass Fiber/Epoxy Composites by Spray Coating (형상이 다른 나노입자 스프레이 코팅에 따른 탄소계 강화 유리섬유와 에폭시 수지간 계면강도 관찰)

  • Kwon, Dong-Jun;Wang, Zuo-Jia;Choi, Jin-Young;Shin, Pyeong-Su;Lee, En-Seon;Park, Joung-Man
    • Composites Research
    • /
    • v.27 no.3
    • /
    • pp.109-114
    • /
    • 2014
  • Manufacture of nancomposites has simple process for developing nanocomposites due to the increasing applications using nanofillers. This work studied nanofiller coated glass fiber for reinforcing material with good wetting and conductivity and the morphology of nanofiller coated glass fiber was analyzed by FE-SEM. The durability of reinforced glass fiber was investigated with different shapes of nanofillers using sonication rinsing method. Fatigue test was performed to evaluate the adhesion of reinforcing interface and stability of nanofiller coating layer for single fiber reinforced composites. Apparent modulus and conductivity of nanofiller coating layer were evaluated to realize multifunctional of nanocomposites. Fiber type of nanofiller was better than plate type due to better cohesion between fiber and nanofillers. At last, the stability of fiber type nanofiller of coating layer has better durability and conductivity than plate type case.

A Study on the Effect of Fiber Orientation on Impact Strength and Thermal Expansion Behavior of Carbon Fiber Reinforced PA6/PPO Composites (탄소섬유 강화 PA6/PPO 복합재료의 섬유 배향에 따른 충격강도 및 열팽창 거동에 관한 연구)

  • Won, Hee-Jeong;Seong, Dong-Gi;Lee, Jin-Woo;Um, Moon-Kwang
    • Composites Research
    • /
    • v.27 no.2
    • /
    • pp.52-58
    • /
    • 2014
  • Short fiber reinforced composites manufactured by injection molding have diverse fiber orientations variable with measuring positions even in the same specimen, which is caused by the flow induced fiber orientation. Fiber orientations considerably affect the mechanical and thermal properties of final composite products. In this study, fiber orientation of injection molded carbon fiber reinforced PA6/PPO composite was measured at several points of the specimen by optical microscopy analysis and the corresponding izod impact strength, coefficients of thermal expansion (CTE) were also measured to investigate the influence of local fiber orientation on the mechanical and thermal properties. Izod impact strength where fiber was perpendicular to the direction of crack propagation was higher than where fiber was parallel to the direction, which could be explained be the impact resistance reinforcing mechanism by fiber orientation. CTE was also lower where fiber was parallel to the measurement direction of CTE than where fiber was perpendicular to the direction, which could be also explained by the dimensional stability mechanism by fiber orientation.

A Study on the Residual Stresses Using Elatoplastic Analysis in Metal matrix Composites (단섬유 금속복합재료의 탄소성 잔류응력해석)

  • 김흥건
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 1996.10a
    • /
    • pp.173-179
    • /
    • 1996
  • A computer simulation has been performed for the application to the elastoplastic stress analysis in a discontinuous composite solid. To obtain the internal field quantities of composite the micromechanics analysis and finite element analysis (FEA) were implemented. As the procedure the reasonably optimized FE mesh generations the appropriate imposition of boundary condition and the relevant postprocessing such as elastoplastic thermomechanical analysis were taken into account. For the numerical illustration an aligned axisymmetric single fiber model has been employed to assess field quantities. It was found that the proposed simulation methodology for stress analysis is applicable to the complicated inhomogeneous solid for the investigation of micromechanical behavior.

  • PDF

Mode II Interlaminar Fracture Toughness of Hybrid Composites Inserted with Different Types of Non-woven Tissues (종류가 다른 부직포가 삽입된 하이브리드 복합재료의 모드 II 층간파괴인성)

  • Jeong, Jong-Seol;Cheong, Seong-Kyun
    • Composites Research
    • /
    • v.26 no.2
    • /
    • pp.141-145
    • /
    • 2013
  • The mode II interlaminar fracture toughness was evaluated for CFRP laminates with different types of nonwoven tissues and the source of increased mode II interlaminar fracture toughness was examined by SEM analysis in this paper. The interlaminar fracture toughness in mode II is obtained by an end notched flexure test. The experiment is performed using three types of non-woven tissues: 8 $g/m^2$ of carbon tissue, 10 $g/m^2$ of glass tissue, and 8 $g/m^2$ of polyester tissue. On the basis of the specimen with no non-woven tissue, interlaminar fracture toughness on mode II at specimens inserted with non-woven carbon and glass tissues and polyester tissues increases as much as 166.5% and 137.1% and 157.4% respectively. The results show that mode II interlaminar fracture toughness of CFRP laminates inserted with nonwoven tissues increased due to the fiber bridging, fiber breakage, and hackle etc. by SEM analysis.

A Study on the Effents of High Temperature Heat Treatment on the Physical and Mechanical Properities of Carbon Fiber and Carbon Composites (탄소섬유 및 탄소복합재의 물리적/기계적 특성에 대한 고온열처리의 영향 연구)

  • Kim, Dong-Gyu;Ha, Heon-Seung;Park, In-Seo;Im, Yeon-Su;Yun, Byeong-Il
    • Korean Journal of Materials Research
    • /
    • v.4 no.3
    • /
    • pp.287-294
    • /
    • 1994
  • PAN-based carbon fiber roving and fabric were heat treated at the temperature of $2170^{\circ}C$. Using non-heat treated and heat treated fabric, greenbodies of CFRP and GFRP were manufactured in the Autoclave. After the analysis of heat treated and non-heat treated carbon fiber roving and two types of greenbodies, the variations of physical and mechanical properties of carbon fibers and greenbodies with heat treatment were studied. Observing the cross-section of carbon fiber with SEM, we knew the diameter of carbon fiber was decreased from 6.8gm to 6.4p1. The results of TGA showed that the oxidation resistence was enhanced after heat treatment. The tensile strength of carbon fiber was decreased from (3.11$\pm 0.32)\times 10^3$ MPa to (1.87$\pm 0.26)\times 10^3$MPa, but tensile modulus was increased from (1.94$\pm 0.06)\times 10^5$ MPa to (2.02$\pm 0.11)\times 10^5$MPa after heat treatment. The interlaminar shear strengths of CFRP and GFRP were 148.8$\pm$1.6Mpa and 82.2$\pm$1.1Mpa, respectively. Torch test showed that CFRP was abraded smoothly but GFRP was delaminated.

  • PDF

Structural Performance of Reinforced Concrete Shear Columns Strengthened with Sprayed Fiber Reinforced Polymers (Sprayed FRP로 보강된 철근 콘크리트 전단기둥의 보강성능 평가)

  • Lee, Kang Seok;Byeon, In Hee;Lee, Moon Sung
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.11 no.3
    • /
    • pp.132-142
    • /
    • 2007
  • In this study, a structural performance of R/C columns controlled by shear, strengthened with Sprayed FRP, was investigated. For this purpose, six 2/3-scaled column specimens were designed and tested by the pseudo-static reversed cyclic load under a constant axial load, which is 10% of the nominal axial strength of the column. Four specimens were strengthened by Sprayed FRP with different combinations of short fibers (carbon or glass) and resins (epoxy or vinyl ester). For comparison purpose, tests of a specimen strengthened with carbon fiber sheet (CFS) and a control specimen without strengthening were carried out, respectively. The result reveals that shear strengths and ductility capacities of columns strengthened with Sprayed FRP improved remarkably, compared to those of the control column, and the Sprayed FRP technique developed in this study is able to use the strengthening scheme of existing R/C columns.

A Study on Microfailure Mechanism of Single-Fiber Composites using Tensile/Compressive Broutman Fragmentation Techniques and Acoustic Emission (인장/압축 Broutman Fragmentation시험법과 음향방출을 이용한 단섬유 복합재료의 미세파괴 메커니즘의 연구)

  • Park, Joung-Man;Kim, Jin-Won;Yoon, Dong-Jin
    • Composites Research
    • /
    • v.13 no.4
    • /
    • pp.54-66
    • /
    • 2000
  • Interfacial and microfailure properties of carbon fiber/epoxy matrix composites were evaluated using both tensile fragmentation and compressive Broutman tests with an aid of acoustic emission (AE) monitoring. A polymeric maleic anhydride coupling agent and a monomeric amino-silane coupling agent were used via the electrodeposition (ED) and the dipping applications, respectively. Both coupling agents exhibited significant improvements in interfacial shear strength (IFSS) compared to the untreated case under tensile and compressive tests. The typical microfailure modes including fiber break of cone-shape, matrix cracking, and partial interlayer failure were observed during tensile test, whereas the diagonal slippage in fiber ends was observed under compressive test. For both loading types, fiber breaks occurred around just before and after yielding point. In both the untreated and treated cases AE amplitudes were separately distributed for the tensile testing, whereas they were closely distributed for the compressive tests. It is because of the difference in failure energies of carbon fiber between tensile and compressive loading. The maximum AE voltage for the waveform of carbon or basalt fiber breakages under tensile tests exhibited much larger than those under compressive tests, which can provide the difference in the failure energy of the individual failure processes.

  • PDF

Thermal Properties according to Content and Alignment of Carbon Fiber in Cu Matrix Composite Reinforced with Chopped Carbon Fiber (탄소 단섬유가 첨가된 Cu기지 복합재료의 섬유 분율 및 배열에 따른 열적 특성)

  • Kim, Minkyoung;Han, Jun Hyun
    • Korean Journal of Materials Research
    • /
    • v.31 no.11
    • /
    • pp.626-634
    • /
    • 2021
  • Cu matrix composites reinforced with chopped carbon fiber (CF), which is cost effective and can be well dispersed, are fabricated using electroless plating and hot pressing, and the effects of content and alignment of CF on the thermal properties of CF/Cu composites are studied. Thermal conductivity of CF/Cu composite increases with CF content in the in-plane direction, but it decreases above 10% CF; this is due to reduction of thermal diffusivity related with phonon scattering by agglomeration of CF. The coefficient of thermal expansion decreases in the in-plane direction and increases in the through-plane direction as the CF content increases. This is because the coefficient of thermal expansion of the long axis of CF is smaller than that of the Cu matrix, and the coefficient of thermal expansion of its short axis is larger than that of the Cu matrix. The thermal conductivity is greatly influenced by the agglomeration of CF in the CF/Cu composite, whereas the coefficient of thermal expansion is more influenced by the alignment of CF than the aggregation of CF.