• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.11a
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• pp.50-53
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• 2000

The effect of punching density on the mechanical and thermal properties of nonwoven needle-punched carbon/phenol composite was studied. The carbonized preforms were farmed into composites with phenol resin. The interlaminar shear, tensile and flexural strengths were increased with increasing punching density. However, excessive punching density decreased interlaminar shear and tensile strengths. Erosion rate of carbon/phenol composite was decreased with increasing punching density

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.4
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• pp.96-100
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• 1997

Tensile properties of carbon fiber reinforce composite laminates with non-woven carbon mat are evaluated in this paper. Composite laminates are made by inserting non-wovon carbon mat between layers, The specimens were cut and polished according to ASTM standard . Longitudinal and Transverse Young's modulus are obtained by tensile test. Young's moduli without non-woven carbon mat are compared with those with non-woven carbon mat. Longitudinal and Transverse tensile strength are also investigated. Experimental results show that the transverse Young's modulus of composite materials with non-woven carbon mat is about 10% higher than that of composite materials without non-woven carbon mat. Longitudinal tensile strength of composite materials with non-woven carbon mat is about 24% higher than that of composite materials without non-woven carbon mat. Transverse tensile strength and torughness also increase by inserting non-woven carbon mat between layers.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.239-241
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• 1999

Recently, the friction and wear behaviors of UHMWPE, ceramic and metal is being researched actively for the use as an artificial hip-joint. In this study, because of good wear properties of carbon fiber, we made experiments about the friction and wear of carbon fiber reinforced epoxy composite under the lubricative and the dry condition. The possibilities of carbon-carbon composite for the artificial hip joint application was studied from this results.

• Analytical Science and Technology
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• v.19 no.5
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• pp.376-382
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• 2006

In this work, pitch/activated carbon/$TiO_2$ composite were prepared by $CCl_4$ solvent method with different mixing ratios. The BET surface area of pitch/activated carbon/$TiO_2$ composite has a significantly increase with increasing activated carbon content in pitch/activated carbon/$TiO_2$ composite. The surface structure and elemental compositions of the composite were studied by SEM and EDX, respectively. The SEM results were presented to the characterization of porous texture on the pitch/activated carbon/$TiO_2$ composite. And EDX data was shown the presence of C, O, S, Ti and other elements. The structural properties of the composite were studied in XRD measurements. The $TiO_2$ crystal phases of the pitch/activated carbon/$TiO_2$ composite had lots of rutile-type structure which transforms from anatase-type with a little of anatase-type structure. The photocatalytic activities of the composite were evaluated using a photo-decomposition method under UV lamp. The pitch/activated carbon/$TiO_2$ composites were observed better photocatalytic activity than that of pristine $TiO_2$.

• Journal of the Korea Institute of Building Construction
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• v.2 no.3
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• pp.131-138
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• 2002

The objective of the study is to examine the characteristic correlations between reinforcing carbon fiber and interfacial adhesion agent since the interfacial adhesion strength between reinforcing carbon fiber and matrices is believed to be an essential element influencing the physical properties in carbon fiber reinforced cement composite using slurry method. The integrity of interfacial adhesion between reinforcing fiber and cement not only affects the quality of fiber reinforced cement composite but also influences to a large degree the physical properties of the cement composite when producing carbon fiber reinforced cement composite using slurry method. Having analyzed the physical properties 1.e., water content, tensile strength, flexural strength and flexural toughness of carbon fiber reinforced cement composite specimens, C-PAM(cation polyacrylamide) was determined to be an optimum interfacial adhesion agent. The study has also demonstrated that interfacial adhesion strength varies largely on the content and type of the reinforcing fiber. Judging from magnified view of the tensile shear cross-section using VMS(video microscope system), interfacial adhesion strength between reinforcing fiber and matrices is affected by the type of interfacial adhesion agent. According to the result of the experiments, C-PAM was determined to be an ideal interfacial adhesion agent when using carbon fiber in producing carbon fiber reinforced cement composite with the optimum content of carbon fiber being established.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.29-32
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• 2002

The mechanical and thermal properties of spun carbon fabric/continuous carbon fabric interplay hybrid composite materials have been studied. The properties of the hybrid composites are compared with those of the continuous carbon fabric/phenolic composites and spun carbon fabric /phenolic composites. Through hybridization, tensile strength and flexural strength of hybrid composites were increased by about 17%, and 10%, respectively compared with spun carbon composites. The thermal conductivity of the hybrid composite is lower approximately 4~6% along the direction parallel to the laminar plane than that of the continuous carbon/phenolic composite.

• Carbon letters
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• v.2 no.3_4
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• pp.165-169
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• 2001

Modification of C/C composite bipolar plate for improving electrical conductivity was carried out by addition of electroconductive carbon black (EC-CB). Carbon black was carefully mixed to methanol-containing phenolic resin, impregnated into 2D-carbon fabrics, hot pressed and then carbonized to obtain composite plate. Inclusion of electro-conductive carbon black enhanced the electrical conductivity of the C/C composites by increasing the conduction path. Addition of 10 vol% carbon black increased the electrical conductivity from 5.5/${\Omega}cm$ to 32/${\Omega}cm$ and reduced the crack formation by filling effect, resulting in the increase of flexural properties of composite plate. However, at carbon black content over 10 vol%, flexural properties decreased by delaminating role of excess carbon black at the interface in C/C composites.

• Carbon letters
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• v.7 no.4
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• pp.241-244
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• 2006

Carbon/Carbon composite was been manufactured by the technology of warmer-molding process of clutter chopped carbon fiber, using phenolic resin as an adhesive. The degree of graphitization, the microstructure and the friction properties were studied. The results show that the clutter chopped carbon fiber fully scatter in the Carbon/Carbon composite and the degree of graphitization of phenolic resin can reach up to 86.2%, this matrix carbon can form the continuous and stable graphitic thin film on the friction surface during braking process so that the composite has fine friction properties and low wear rate.

• Carbon letters
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• v.14 no.4
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• pp.251-254
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• 2013

In this study, poly(amic acid) was prepared via a polycondensation reaction of 3,3'-dihydroxybenzidine and pyromellitic dianhydride in an N-methyl-2-pyrrolidone solution; reduced graphene oxide/polybenzoxazole (r-GO/PBO) composite films, which significantly increased the electrical conductivity, were successfully fabricated. GO was prepared from graphite using Brodie's method. The GO was used as nanofillers for the preparation of r-GO/PBO composites through an in situ polymerization. The addition of 50 wt% GO led to a significant increase in the electrical conductivity of the composite films by more than sixteen orders of magnitude compared with that of pure PBO films as a result of the electrical percolation networks in the r-GO during the thermal treatment at various temperatures within the films.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.56-59
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• 2002

This paper presents a study on the permittivities of the E-glass fabric/epoxy composite laminates containing carbon black dispersions at microwave frequency. Measurement showed that the complex permittivities of the composites depend strongly on the natures and concentrations of the carbon black dispersion. A new scheme to obtain a mixing law for the estimation of complex permittivity is proposed. The experimental values of the complex permittivities were compared to those calculated. Simultaneously, the complex permittivity of carbon black itself was also calculated by the scheme.