• Journal of Welding and Joining
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• 제34권4호
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• pp.23-27
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• 2016

A 3D printed metal part and thermal plastic polymer part were joined by direct laser irradiation. The 3D metal part was fabricated by using DED(Direct Energy Deposition) with STS316 material. The experiment was carried out through no patterned metal surface, 3D metal printed surface and micro laser patterned surface. The most secure joining quality was obtained at the laser micro patterned surface specimen and the counterparts of polymers were PLA and PE based thermo plastics. The applied laser power was 350Watt and the distance of patterns was maintained at $150{\mu}m$. The laser line width was optimized at $450{\mu}m$ and the laser micro pattern depth was $180{\mu}m$ for the best joining quality. Based on the result analysis, the possibility of laser material joining for metal to polymer was proposed and multi-material joining will be possible in 3D laser direct material fabrication.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.228-230
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• 2001

We synthesized Bis(3-N-ethylcarbazolyl) terephthalidene(BECP) and Bis(3-7-ethyl-carbazolyl) cyanoterephthalidene(BECCP) and characterized EL properties of these materials. Our device shows a strong blue emission at 472 nm with a luminance efficiency of 0.9 lm/W at a voltage, a current density, and a brightness of 8 V, 5.7 mA/cm$^2$, and 130 cd/m$^2$, respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.285-288
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• 1995

In this Study, it worked to get the degradation characteristics of polymer insulating materials using TSC technique. So, it prepared epoxy composities with sample, the TSC spectroscopy was applied to investigate the influence of interfacial deformation due to inorganic filler and treatments of coupling agents on the network structure and the electrical properties of epoxy composites.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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• pp.273-276
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• 1996

Polyphenylenediamine(PPD) film was prepared with dimethylsulfoxide after the synthesis of PPD by chemical polymerization. The molecular structure of conductive polymer synthesized were discussed by using SEM, FT-IR, NMR. The electrical conductivity measurements were carried out at room temperature. The electrical conductivity which was obtained from electrical instrument was 1.98${\times}$10$\^$-2/ S/cm at ambient temperature.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.203-204
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• 2003

Generally, polymeric foam has many advantages, such as light-weight, good impact absorptivity and adiabatic properties. Poly (ethylene terephthalate) PET has good recyclability and no toxicity. Hence, if we make foam of PET, it could be used for various applications such as heat insulating material, recyclable packing material, and food vessel. Thus these properties are attractive interests to manufacturers. (omitted)

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 가을 학술발표회 논문집
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• pp.432-435
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• 2001

Polymer/clay nanocomposites have received much attention in recent years, because they often exhibit physical properties that are dramatically different from those observed in their micro- and rnacrocornposite counterparts. The presence of clay may affect the crystallization behavior of semicrystalline polymer. (omitted)

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.391-394
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• 2000

EPDM/silicone blend was prepared with polyorganosiloxane compatibilizer for out-door polymer insulation used to shed. Each blend had various weight ratios, 100/0, 90/10, 70/30, 50/50, 30/70, 10/90, and 0/100 as EPDM to silicone, and electrical and tracking characteristics were studied with the method of IEC 60587. And also, tracking properties and contact angle related to UV-weathering period were studied to understand the degree of degradation of blend after 1000 h UV-weathering.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.128-131
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• 2000

The main objective of this paper is to design and test a new type of polymer ZnO surge arrester for DC power system of railroad vehicles. The rated voltage is 1500V direct current. The main research works are focused on structure design by finite element method, rating voltage, temporary over voltage and studies of characteristics of polymeric surge arrester.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.191-194
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• 2007

In hot embossing lithography which has shown to be a good method to fabricate polymeric patterns for IT and bio components, it is very important to determine the proper process conditions of pressure, temperature, and time. It is also a key factor for predicting the optical properties of final product to calculate residual stress distribution after the embossing process. Therefore, to design the optimum process with right conditions, the ability to predict viscoelastic behavior of polymer during and after the hot embossing process is required. The objective of the present investigation is to establish simulation technique based on constitutive modeling of polymer with experiments. To analyze deformation behavior of viscoelastic polymer, the large strain material properties were obtained from quasi-static compression tests at different strain rates and temperatures and also stress relaxation tests were executed. With this viscoelastic material model, finite element simulation of hot embossing was executed and stress distribution is obtained. Proper process pressure is very important to predict the defect and incomplete filling.

• 공업화학
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• 제21권2호
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• pp.115-128
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• 2010

마이크로 프로세서 및 항공 우주산업의 기술 발전에 따른 냉각 조건이 까다로워짐에 따라 각종 산업에서 열 전도 향상을 통한 기기 내에서 외부로의 열 배출은 최근 각광을 받고 있다. 특히 열 전도성 고분자 복합재료의 경우 매우 다양한 물질을 사용하여 그 요구조건에 맞는 부품의 생산이 가능하고 가공 편의성으로 인한 마이크로 부품에서부터 큰 부속품까지 그 사용 범위가 넓다. 방열 소재로 사용되는 고분자 복합재료의 열전도도 예측 모델 식을 알아보고 방열 소재에 대해 알아보며 상업적으로 많이 사용되고 있는 충전제에 대해 다룬다. 또한 최근의 고분자 복합재료 방열소재의 동향에 대해 알아본다.