• 한국산학기술학회논문지
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• 제9권6호
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• pp.1548-1554
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• 2008

은을 이용한 PMC (precious metal clay; 은점토)는 최근 신속한 조형이 가능하여 공예품의 제작용도로 시장이 확대되고 있다. 손으로 직접 조형되는 특성 때문에 PMC자체가 친환경적이어야 하며 소결온도에 따라 적정한 강도와 수축율이 보장되어야 한다. 이미 알려진 선진사의 PMC의 바인더와 달리, 팜오일, 글리콜릭산, 물을 주성분으로 한 새로운 바인더를 제안하여 새로운 PMC를 제안하고, 이를 이용하여 디스크형태의 시편을 성형하여 $700{\sim}900^{\circ}C$ ($50^{\circ}C$간격)구간에서 15분간 소결하여 이들의 경도, 무게변화, 수축률, 소결밀도, 미세구조변화 특성을 선진사의 PMC의 특성과 비교하였다. 제안된 PMC는 선진사의 것과 물성을 비교하여 조형용으로 사용 가능하다고 판단되었으며 $850^{\circ}C$-15분 조건이 조형물 제작에 유리한 소결 조건임을 확인하였다.

• 복합신소재구조학회 논문집
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• 제6권4호
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• pp.58-63
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• 2015

The purpose of this experimental research is to evaluate the workability and strength properties of hybrid fiber reinforced concrete containing amorphous steel fiber and organic fiber. For this purpose, the hybrid fiber reinforced concrete containing amorphous steel fiber(ASF) with polyamide(PA) and polyvinyl alcohol(PVA) fiber, respectively were made according to their total volume fraction of 0.5% for water-binder ratio of 33%, and then the characteristics such as the workability, compressive strength, and flexural strength of those were investigated. It was observed from the test results that the workability and compressive strength at 7 and 28 days were decreased and the flexural strength at 7 and 28 days was increased with increasing ASF and decreasing organic fiber.

• 한국수소및신에너지학회논문집
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• 제16권2호
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• pp.150-158
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• 2005

Added ratio of 8YSZ powder and organic compounds (solvent, plasticizer, dispersant, binder) properly. It manufactured electrolysis membrane by wet process that make slurry and dry process that do not use organic compounds. In the case of wet process, harmony combination and method of organic compound are an importance element in slurry manufacture. This slurry did calcine at temperature of 140$^{\circ}C$ in Furnace and manufactured electrolyte disk by Dry pressing method. Like this, manufacturing disk sintered at temperature of $1300^{\circ}C,\;1400^{\circ},\;1500^{\circ}C$ in Furnace and completed electrolysis membrane. Confirmed change of crystal structure and decision form through analysis of density, SEM, XRD according to change of sintering temperature, and considered relation with ion conductivity.

• Carbon letters
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• 제13권4호
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• pp.191-204
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• 2012

Carbon nanotubes (CNTs) have exceptional mechanical, electrical, and thermal properties compared with those of commercialized high-performance fibers. For use in the form of fabrics that can maintain such properties, individual CNTs should be held together in fibers or made into yarns twisted out of the fibers. Typical methods that are used for such purposes include (a) surfactant-based coagulation spinning, which injects a polymeric binder between CNTs to form fibers; (b) liquid-crystalline spinning, which uses the nature of CNTs to form liquid crystals under certain conditions; (c) direct spinning, which can produce CNT fibers or yarns at the same time as synthesis by introducing a carbon source into a vertical furnace; and (d) forest spinning, which draws and twists CNTs grown vertically on a substrate. However, it is difficult for those CNT fibers to express the excellent properties of individual CNTs as they are. As solutions to this problem, post-treatment processes are under development for improving the production process of CNT fibers or enhancing their properties. This paper discusses the recent methods of fabricating CNT fibers and examines some post-treatment processes for property enhancement and their applications.

• 한국염색가공학회지
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• 제32권4호
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• pp.274-280
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• 2020

This study compared the mechanical properties of bamboo fiber composites and kenaf fiber composites through physical treatment (ultrasonic treatment). Kenaf, a composite of PP reinforced with bamboo fiber, was made using injection molding technology. PP was used as a binder and the ultrasonic treatment time of bamboo and kenaf was increased by 30 minutes to compare and study various mechanical properties of bamboo and kenaf composites through physical treatment. Interfacial properties such as internal cracks and internal structure of the wave cross section were confirmed using a scanning electron microscope (SEM). As a result of the ultrasonic treatment, most of the characteristics were fragile as the ultrasonic treatment time was increased, and it was confirmed that the natural characteristics of the twisted fibers had a great influence on the characteristics of the composite material.

• KIEAE Journal
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• 제8권5호
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• pp.55-60
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• 2008

The purpose of this study is to increase the use of Hwangto and examine the strength according to what it is compounded with. Hwangto-concrete containing Hwanto without cement nor organic chemical products were compared to the traditional cement concrete through some durability experiments. We expect to gain more knowledge on the potentials of Hwangto-concrete as an architectural source. 1) As Hwangto binder amount rises, the value of slump increases too. The reason is that the increase of the quantity of cement causes the increase of the amount of material and the decrease of the amount of aggregate. 2) When the mixed component into Hwangto-concrete remains at 2%, the compress strength is generally dispersed high along the per unit fission, in case the amount of which is at $400(g/m^3)$. The highest compress strength is 39MPa. It means that it can be applied to common structures and we need to conduct a basic property test to ensure the strength and fluidness. 3) Hwangto-concrete is expected to be highly used in the ocean structure and chemical industry because it has better resistance to sulfuric acid and to hydrochloric acid than the cement-concrete has. The result of this study is as follows. It is expected that Hwangto-concrete will be widely applied and further research on its durability and tests for its basic substantial characteristics based on future component added to it.

• 한국전기전자재료학회논문지
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• 제30권5호
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• pp.318-324
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• 2017

Powder compaction technology is widely used to prepare thermal battery components. This method, however, is limited by the size, thickness, and geometry of the battery components. This limitation leads to excessive cell capacity, overweight, and higher cost of the pellets, which decreases the specific capacities and delays the activation time of thermal batteries. $FeS_2$ thin-film cathodes were fabricated by tape-casting technology and analyzed by SEM and EDS in this paper. The residual organic binder of the $FeS_2$ thin-film cathodes decreased with the temperature of the heat treatment, which improved the specific capacity because of the lower resistance. Specific capacities of the $FeS_2$ thin-film cathodes decreased because of the higher residual binder and the restrictive reaction of active materials with molten salts as the thickness increased. $FeS_2$ thin-film cathodes showed much higher specific capacity (1,212.2 As/g) than pellet cathodes (860.7 As/g) at the optimal heat-treatment temperature ($230^{\circ}C$).

• 한국전기전자재료학회논문지
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• 제25권6호
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• pp.426-430
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• 2012

The properties of green sheet were investigated in order to understanding an effects of organic solvent mixture ratio for solid oxide fuel cells fabrication. The purpose of this work is to optimize the slurry condition using the design of experiment to improve green sheet properties. The elongation increased with increasing amount of binder and solvent. With increasing amount of solvent, the air permeability increased but the tensile strength decreased. The best properties of the green sheet appeared amount of the binder 17 wt%, solvent 35 wt% and powder 48 wt%. The optimum condition of green and sintered density for solid oxide fuel cells fabrication was obtained in the sample pressured at 800 $kgf/cm^2$.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 추계학술대회 초록집
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• pp.172.1-172.1
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• 2011

본 연구에서는 매립지에서 발생하는 주요한 가스인 $CO_2$(47~55%)와 $CH_4$(47~55%)가스를 분리하기 위하여 여러 $CO_2$ capture 방법 중 Zeolite를 사용한 흡착법을 이용하였다. 국내에서 시판되고 있는 powder형 Zeolite 13X에 Inorganic binder와 organic binder를 최적의 비율로 혼합한 후 증류수를 이용하여 Pellet type 흡착제를 제조하였다. 또한 최종적으로 $CO_2$의 흡착능을 높이기 위하여 양이온(1M의 KCl, NaCl, $CaCl_2$, $LiCl_2$)으로 이온교환을 하였다. 매립지 모사가스($CO_2$:40%, $CH_4$:60%)를 이용하여 실시간 분석기(Delta1600S)를 이용 두 가스의 분리와 $CO_2$ 흡착성능(mg-CO2/g-흡착제)을 확인하였다. 개발된 흡착제(AjouEpl 13X)는 ICP, XRD, XRF, BET 분석으로 제올라이트의 구조와 성분을 분석하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.381-381
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• 2011

In this study, a TiO2 colloidal sol was synthesized by sol-gel process, which was used as a "glue" agent to enhance interconnection of TiO2 particles in low temperature process for plastic dye sensitized solar cell. The crystalline phase of this TiO2 glue is pure anatase with average particles size of 5 nm, which was characterized by powder X-ray diffraction and high revolution-TEM. The viscous alcoholic paste without any organic binder was prepared from the mixture of commercial P25 powder and glue. Paste composition and sintering process parameters were optimized for high photovoltaic performance based on low temperature process. The electrochemical impedance spectroscopy and photocurrent-photovoltage transient spectroscopy were also employed to investigate the mechanism of electron transport in this binder free TiO2 film system.