• 한국재료학회지
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• 제17권11호
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• pp.601-605
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• 2007

The tribological properties of acrylonitrile-butadiene rubber (NBR) filled with two kinds of carbon black filler were examined. Different types of Semi-Reinforcing Furnace (SRF), and High Abrasion Furnace (HAF) blacks were used as filler material to test the influence of carbon black particle size on the friction and wear of NBR. Results from tribological tests using a ball on disk method showed that the smaller HAF particles were more effective for reducing the wear of NBR during frictional sliding. The hardness, elastic modulus at 100% elongation, and elongation at break were measured to examine the correlation between the effects of carbon black on the mechanical and tribological properties of the NBR specimens. The wear tracks of the NBR specimens were observed with scanning electron microscopy (SEM). The wear tracks for NBR with different ratios of SRF and HAF showed clearly different abrasion patterns. Mechanisms for the friction and wear behavior of NBR with different sizes of carbon black filler were proposed using evidence from wear track observation, as well as the mechanical and tribological test results.

• Elastomers and Composites
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• 제41권3호
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• pp.194-204
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• 2006

본 연구에서는 카본블랙 충전제의 입자크기 및 구조에 따른 고무 배합물의 마찰 마모 특성을 고찰하였다. 카본블랙의 입자크기와 구조에 따라 마모속도 및 형상이 다르게 되며, 최적 마모성능을 설계하기 위해서는 충전제의 입자크기와 구조의 마모 영향도를 사용조건에 따라 고려하여야 한다. 충전제의 입자크기와 구조에 따른 마모속도($W_R$) 영향도를 수준별로 고찰하기 위해 본 연구에서는 구조와 입자크기가 다른 10가지의 카본블랙을 선택하여 동일한 양을 천연고무와 배합하였다. 자체 제작한 칼날형 마찰 마모 시험기를 이용하여 마찰 마모 특성을 평가하였고, 카본블랙의 입자크기와 구조의 영향을 고려한 특성인자(${\psi}=\sqrt{{N_2^2}+{DBP^2}}$)와의 관계를 고찰하였다. 마모속도($W_R$)와 마찰일($W_f$)의 간에는 power-law 관계가 있었으며, 마모속도는 카본블랙의 특성인자에 역비례 관계를 보였다. 이는 카본블랙의 입자 크기가 작고 구조가 잘 발달 될수록 마모 저항특성은 향상된다는 것을 나타낸다.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 추계학술발표대회 논문집
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• pp.234-237
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• 2003

The absorption and the interference shielding of the electromagnetic wave problem have been a very important issue for commercial and military purposes. This study dealt with the simulation reflection loss for electromagnetic absorbing sandwich type structures in X-band(8.2Ghz~12.4GHz). Glass/epoxy composites containing conductive carbon blacks were used for the face sheets and styrofoams were used for the core. Their permittivities in X-band were measured using the transmission line technique. Simulation results of 3-1ayered sandwich type structures showed the reflection loss using the theory about transmission and reflection in a multi-layered medium.

• Elastomers and Composites
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• 제33권1호
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• pp.17-26
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• 1998

Natural rubber was filled with 8 commercial carbon blacks covering range of rubber-grade products at different levels of filler loadings in order to investigate physical compound and vulcanizate properties. It was found that the curves of rubber property vs filler loading of both uncured compounds and vulcanizates can be superposed to one single master curve by introducing an effective volume fraction which is based on CDBP. The effective volume fraction, $V_{EFF}$ was utilized to explain the variation of the stiffness of all rubber compounds. The surface area-corrected effective volume fraction, V', was utilized to explain the formation of bound rubber, rebound and lambourn wear.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
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• pp.112-115
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• 2002

The effects of processing aids(P.A.) in semicoductive compounds(S.C.) with highly loaded carbon black for extra high voltage cables were investigated. The processability of S.C. is improved as the contents of P.A. increased, however, the electrical, mechanical properties and smoothness of S.C. grew worse, especially for the S.C. which contains 5wt% of P.A., the volume resistivity after heat cycle which shows long term reliability increased about three times after 15cycles compared to the S.C. which contains no P.A. We inferred that it is caused by the action of P.A. as the insulating sites, thermal expansion of polymer matrix which leads the length between carbon blacks to shorten, and the decrease of degree of crosslinking. The change of ion contents which means cleanliness of S.C. is not occured regardless of the addition of P.A.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.633-637
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• 2001

Oil fly ash is known as one source of raw materials from which vanadium and nickel metals can be recovered. The current recovery process of valuable metals from oil fly ash is mainly the hydrormetallurgy one. Nevertheless, a great amount about 50~80%, of unburned carbon remains as byproduct after hydrormetallursy process. In Taiwan, if hydrormetallursy processes have proceeded, it can be estimated that the annual production of unburned carbon is 25 thousand tons. From the viewpoint of resource recycling, this study is a preliminary study and investigates in recovery of sub micron- graphitized carbon from unburned carbon by a designed process. The designed process included the following steps: 1.selecting a portion with +400mesh size from unburned carbon; 2.treating the selected in ultrasonic waves; 3.using a 400mesh sieve to obtain the product which is under 400mesh; 4.Removal ash from the product. In regard to treatment by ultrasonic waves in the designed process, treating time of ultrasonic waves is a simple and only variance in this study. The results indicate that the production yields increase with the treating time of ultrasonic waves; the production yield in specific conditions of this study can reach about 23%, in which ash content in product is about 2.5%. According to results of SEM, TEM and XRD, the products from the designed process are flakes in shape, several microns in size and graphitized carbon in carbon crystal phase. Except to graphitized carbon, there are a little carbon blacks, which are graphite 2H in carbon crystal phase in the products. Conclusively, the designed process is possibly applicable, by which comes to the recovery of micron- graphitized carbon.

• Composites Research
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• 제15권2호
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• pp.18-23
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• 2002

군사적 목적뿐만 아니라 상업적 목적에서도 레이더나 기타 전자파를 방출하는 기기들로부터 생성되는 전자파의 흡수 또는 차폐는 매우 중요한 일이다. 본 연구에서는 다른 유전적 성질을 가지는 복합재층을 배열하여 전자기파의 반사를 최소화하는 연구를 수행하였다. Glass fabric/epoxy에 전도성을 가지는 카본블랙 분체를 혼합한 복합재와 Carbon fabric/epoxy 복합재 대만 유전성질을 측정하였고, 이를 이용하여 X-band(8.2 GHz-l2.4GHz)에 대한 전자기파 반사의 최소화 구조를 구성하였다. 두께2.6mm의 다층 구조로 최대 30dB 이상의 반사 손실과 최대 흡수 주파수로부터 2GHz 주파수 대역에 걸쳐 10dB이상의 반사손실을 일으킬 수 있었다.

• 한국응용과학기술학회지
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• 제20권3호
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• pp.212-220
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• 2003

Electrical properties of carbon filler/PVdF [poly(vinylidene fluoride)] composite were investigated as a funtion of carbon filler/PVdF ratio in the range of 0.2${\sim}$0.5. Three kinds of comercialzied conductive carbon blacks such as Hiblack 41Y, KE300J, and KE600J, and carbon nanofibers prepared by the catalytic chemical vapor deposition of $C_2H_4$ over Ni-Cu catalysts were used as the carbon fillers. The electrical conductivity of carbon filler/PVdF composites were in the range of 0.65 to 13.5 S/cm depending the fillers' electrical conductivity ranging from 5.6 to 23.1 S/cm. Among the carbon fillers used, the KE600J carbon black showed the highest conductivity both in the composite and filler itself because of its high degree of graphitization due to the high-temperature thermal treatment and its high surface area due to the activation treatment.

• 한국재료학회지
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• 제20권4호
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• pp.204-209
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• 2010

Recent high efficiency electronic devices have been found to have heat emission problems. As for LEDs, an excessive increase in the device temperature causes a drop of the luminous efficiency and circuit lifetime. Therefore, heat release in the limited space of such electronic parts is very important. This is a study of the possibility of using a coating of carbon materials as a solution for the thermal emission problem of electronic devices. Powdered carbon materials, cokes, carbon blacks, amorphous graphite, and natural flakes were coated with an organic binder on an aluminum sheet and the subsequent thermal emissivity was measured with an FT-IR spectrometer and was found to be in the range of $5{\sim}20\;{\mu}m$ at $50^{\circ}C$. The emissivity of the carbon materials coated on the aluminum sheet was shown to be over 0.8 and varied according to carbon type. The maximum thermal emissivity on the carbon black coated-aluminum surface was shown to be 0.877. The emissivity of the anodized aluminum sheets that were used as heat releasing materials of the electronic parts was reported to be in the range of 0.7~0.8. Therefore, the use of a coating of carbon material can be a potential solution that facillitates heat dissipation for electronic parts.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.481-481
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• 2007

This work describes the effect of the number of roll pressing and the composition of carbon black on the electric and mechanical properties of carbon-PTFE electrode, in which composition is MSP 20 : carbon black: PTFE = 95-x : x : 5 wt.%. It was found that the best electric and mechanical properties were obtained in sheet electrode roll-pressed for about 15 times and in sheet electrode, in which composition is MSP 20 : carbon black: PTFE = 80 : 15 : 5 wt.%. These behaviors could be explained by the network structure of PTFE fibrils and conducting paths linked with carbon blacks, respectively. On the other hand, cell capacitor using the sheet electrode with 15 wt.% of carbon black attached on aluminum current collector with the electric conductive adhesive, in composition is carbon black : CMC = 70 : 30 wt.%, has exhibited the best rate capability in the current range of $0.5mA/cm^2$ $100mA/cm^2$ and the lowest equivalent series resistance.