• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.89-89
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• 2010

발전기 회전자 권선 층간절연지는 대부분 글라스-에폭시(Glass-Epoxy) 및 페놀수지 제품이 사용되고 있다. 이 층간절연지는 과도하게 열적, 기계적 응력을 받게 됨으로 높은 기계적 특성이 요구된다. 실제 장기간 사용된 층간절연지에 대해 기계적 인장특성을 분석하였으며 시험결과 운전년수와 기계적 특성 저하와는 뚜렷한 상관관계가 없는 것으로 판단되었다.

• Composites Research
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• v.32 no.2
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• pp.90-95
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• 2019

Sloshing impact loads on liquefied natural gas (LNG) carr iers are the main issue of damage to the insulation system in LNG cargo containment system (LNG CCS). The damage to the insulation system would be fatal in maintaining a temperature-savings environment in LNG CCS. The typical method is to enhance the insulation materials that can maintain a constant cryogenic temperature. Insulation materials consist of polyurethane foam and plywood, an adhesive for bonding these two materials. This study intends to improve the absorption energy of the material when the impact load is applied by creating a glass bubble/epoxy composite resin as part of the insulation. The experimental scenarios consider the effect of temperature ($20^{\circ}C$, $-163^{\circ}C$), glass bubble weight fraction in epoxy resin through free fall experiments. Experiments have shown that if the glass bubble additive reaches 20 wt.%, the cryogenic absorption energy is a maximum performance and that 0 wt.% has a maximum ambient absorption energy. However, the agglomeration has been occurred due to deterioration of the stirring performance if weight fraction was 20 wt.% and the result of 0 wt.% have been revealed that ambient absorption energy is significantly lower.

• Journal of the Korean Institute of Telematics and Electronics
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• v.19 no.5
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• pp.5-11
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• 1982

The dielectric slab waveguide is fabricated on the slide glass or oxidized silicon wafer, by spin coating polyurethane, epoxy or photoresist, and the phenomenon of dielectric waveguiding is oboerved. Using the fact that the refractive index of K.P.R. is larger than that of polyurethane, thin film prism with two layered structure is fabricated, and the refraction of light is observed.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.149-154
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• 2018

This paper describes the fabrication and heat transfer property of 50 watts rated LED array module where multiple chips are mounted on chip-on-board type ceramic-metal hybrid substrate with high heat dissipation property for high power street and anti-explosive lighting system. The high heat transfer ceramic-metal hybrid substrate was fabricated by conformal coating of thick film glass-ceramic and silver pastes to form insulation and conductor layers, using thick film screen printing method on top of the high thermal conductivity aluminum alloy heat-spreading panel, then co-fired at $515^{\circ}C$. A comparative LED array module with the same configuration using epoxy resin based FR-4 PCB with thermalvia type was also fabricated, then the thermal properties were measured with multichannel temperature sensors and thermal resistance measuring system. As a result, the thermal resistance of the ceramic-metal hybrid substrate in the $4{\times}9$ type LEDs array module exhibited about one third to the value as that of FR-4 substrate, implying that at least triple performance of heat transfer property as that of FR-4 substrate was realized.