• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.10
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• pp.1761-1766
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• 2016

In this paper, we investigated the fusing current of carbon fiber and thermal properties of carbon fiber and metal shielded cable due to over-current. The fusing current value for the metal-coated carbon fiber was 5.3A in 3K, 7.4K and 13.05A in 12K. And if it exceeds 50% of the fusing current was broken with a rapid voltage rise. In the case of carbon fiber shielded cable, the temperature of the PVC sheath increased somewhat in the allowable current range. However, the temperature of PVC sheath rapidly increased to $128.1^{\circ}C$ in the 2 time allowable current range. This value is $10^{\circ}C$ higher than the temperature of PVC sheath on the metal screen cable, because the resistance of the carbon fiber is high and heat transfer rate is slow.

• Journal of the Korean Society for Heat Treatment
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• v.26 no.2
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• pp.66-71
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• 2013

The purpose of this study is to prepare a high-strength Fiberglass Reinforced Metal (FRM). Aluminum covering over carbon fibers (CF) was made to increase their wettability to molten aluminum. A cylindrical sputtering apparatus was used for the covering. One tow of carbon fibers was placed along the central axis of the cylindrical target. Aluminum was uniformly coated around the carbon fiber tow. But in case of CF without sizing treatment, aluminum spread into the inside of the tow. Preforms of carbon fiber/aluminum composite were made by impregnating carbon fiber with molten aluminum. Contact angle of molten aluminum to the aluminum-coated carbon fiber was about $30^{\circ}$. The fractured section of preform was observed by SEM, which showed that molten aluminum wetted the outer part of the tow well but had not penetrated into the center, and that adhesion between CF and aluminum matrix was in good condition.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.12
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• pp.49-55
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• 2020

In order to improve the electromagnetic shielding rate of Carbon Fiber (CF), it was produced using the nickel nano-powder impregnating method. Using two types of nickel powder having thicknesses of 50 ㎛ and 100 ㎛, and a thermoplastic elastomer resin, a compound containing 10-20% nickel content was mixed and then manufactured through an extruder. The CF coated with the compound was woven and manufactured using a 1-ply specimen. The final nickel content of the specimen was verified using TGA and the distribution of nickel powder on the CF surface was verified using SEM. The metal shows a high shielding rate in the low-frequency band, but the shielding rate decreases at higher-frequency bands. The CF improves at the higher frequency band, and metals reflect electromagnetic waves while carbon absorbs electromagnetic waves. The study of shielding materials, which are stronger and lighter than metal, by using CF lighter than metal and enabling the shielding rate from low-frequency band to high-frequency band, confirmed that the larger the area coated with nickel nano-powder, the better the electromagnetic shielding performance. In particular, CF coated with a thickness of 100 ㎛ has a shielding rate similar to that of copper and can also be used for EV/HEV automotive cables and other applications in the future.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.1
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• pp.243-248
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• 2017

This study used general carbon fibers(CF), which can be utilized for a low voltage cable screen, as well as metal-coated carbon fibers(MCF) to make cables and analyzed the properties of electromagnetic effectiveness. Both braid CF and MCF cables with 3,000 strands, 16 spindles, and braid density of 90% or over were adopted. The tape-type MCF specimens were spread into a tape(width: 15mm) using a hot melt to make a cable. The shield effectiveness was measured up to the 1GHz range in accordance with IEC 62153-4-6; braid shielded cables featured a superior shielding effect at 63dB than tape-type shielded cables. That was because the tape-type shielded cable has relatively more gaps and holes between carbon fibers than the braid type, resulting in a more inflow or emission of electromagnetic waves. In the case of braid cables, the characteristics of their electromagnetic waves were enhanced, with higher spindles and higher conductivity of carbon fibers. The shield effectiveness of the MCF shielded cable, however, was lower than that of tin-coated one.

• Composites Research
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• v.23 no.6
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• pp.1-6
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• 2010

The electrical conductivity of carbon-fiber reinforced plastics (CFRP's) has been improved by indium-tin oxide (ITO) nano-particle coating on carbon fibers for the purpose of lightning strike protection of composite fuselage skins. ITO nano-particles were coated on the surface of carbon fibers by spraying the colloidal suspension with 10~40% ITO content. The electrical conductivity of the CFRP has been increased more than three times after ITO coating, comparable to or higher than that of B-787 composite fuselage skins with metal wire-meshes on the outer surface, without sacrificing the tensile property due to the existence of nano-particles at fiber-matrix interface. The damage area by the simulated lightning strike was also verified for different materials and conditions by using ultrasonic C-scan image. As the electrical conductivity of 40% nano-ITO coated sample surpass that of the B-787 sample, the damage area by lightning strike also appeared comparable to that of the materials currently employed for composite fuselage construction.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.4
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• pp.165-171
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• 2002

The study on the adsorption, the surface properties and the antibacterial effects of the metal-treated pitch based activated carbon fibers was carried out. From the adsorption studies on the series of metal-treated activated carbon fiber, the specific surface areas of the metal treated activated carbon fiber obtained from BET equation were in the range of 113.2~1574 $m^2$/g for the Ag-ACFs. And that of Cu treated ACF are distributed to 688.2-887.8 $\m^2$/g. And, the specific surface areas of the Ni-treated pitch based ACFs were in the range of 692.6~895.2 $\m^2$/g. From the ${\alpha}_s$- method, 0.06~1.1 cm^3/g of the micropore volumes were obtained from Ag-ACFs. And, 0.1~0.2 cm^3/ and 0.2~0.6 cm^3/g of the micropore volumes were obtained from Cu and Ni-ACFs, respectively. And, from the SEM morphology results, it was observed that the surface of activated carbon fiber are partially blocked and coated by metal after the treatment. Finally, from the antibacterial effects of metal-treated activated carbon fiber against E. coli, the areas of antibacterial effect become larger with the increase in mole ratio of metal treated. And, from the antibacterial effects using Shake flask method against E. coli, the percentage of the effects was 92.5~100 % and the antibacterial effect was increased with the increase in mole concentration of metal treated.

• Carbon letters
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• v.9 no.2
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• pp.105-107
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• 2008

In this work, we employed an electroless nickel plating on glass fibers in order to enhance the electric conductivity of fibers. And the effects of metal content and plating time on the conductivity of fibers were investigated. From the results, island-like metal clusters were found on the fiber surfaces in initial plating state, and perfect metallic layers were observed after 10 min of plating time. The thickness of metallic layers on fiber surfaces was proportion to plating time, and the electric conductivity showed similar trends. The nickel cluster sizes on fibers decreased with increasing plating time, indicating that surface energetics of the fibers could become more homogeneous and make well-packed metallic layers, resulting in the high conductivity of Ni/glass fibers.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.1
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• pp.90-94
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• 2023

Carbon fiber(CF) with excellent thermal conductivity and electrical conductivity is attracting attention as an alternative material because metal heating elements have problems such as high heat loss and fire risk. However, since CF is oxidized and disconnected at about 200℃ or higher, the application of heating elements is limited, and CF heating elements in the form of vacuum tubes are currently used in some commercial heaters. In this work, polyimide(PI) with high heat resistance was coated on the surface of carbon fiber by electrophoretic deposition to prevent oxidation of CF in the atmosphere without using a vacuum tube, and the coating thickness and heat resistance were investigated according to the applied voltage. The heater made by connecting the PI-coated CF heating elements in series showed stable heating characteristics up to 292℃, which was similar to the heating temperature result of the heat transfer simulation. The PI layer coated by the electrophoretic deposition method is effective in preventing oxidation of CF at 200℃ or higher and is expected to be applicable to various heating components such as secondary batteries, aerospace, and electric vehicles that require heat stability.

• Composites Research
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• v.33 no.4
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• pp.191-197
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• 2020

In this study, a hybrid metals such as copper (Cu) and nickel (Ni) coated carbon fibers (Ni-Cu/CFs) was prepared by wet laid method to develop a randomly oriented sheet material for high-efficiency electromagnetic interference shielding with the enhanced durability. The prepared sheet materials show a high electromagnetic interference shielding efficiency of 69.4 to 93.0 dB. In addition, the hybrid metals coated Ni-Cu/CFs sheets showed very high durability with harsh chemical/thermal environments due to the effective corrosive and mechanical resistances of Ni surface. In this context, the Ni-Cu/CF sheet possesses longer service life than the Cu/CF sheet, that is, 1.7 times longer.

• Proceedings of the KAIS Fall Conference
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• 2011.12a
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• pp.286-288
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• 2011

활성탄소섬유의 유해 미생물의 번식 억제력을 조사하기 위해 한천베지배양법을 이용하였다. 전이금속으로 코팅된 활성탄소섬유는 일부 유해 미생물에서 번식억제력이 나타났으며, 유해 미생물은 인간의 피부 부종을 야기시키는 미생물인 candida albicans이었다. 그리고 코팅 활성탄소섬유의 흡 탈착력은 코팅되지 않은 활성탄소섬유보다 약 5% 내외로 감소함을 알 수 있었다.