• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.10a
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• pp.142-147
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• 2003

고분자 애자용 재료로 EPDM, 폴리에틸렌, 에폭시, 실리론 고무 등이 사용되고 있으며, 이중 실리콘 고무는 내후성, 내트랙킹성, 내아크성, 내환경성, 발수성등이 우수하다는 것이 많은 연구를 통해 밝혀졌다. 그러나, 옥외용 고분자는 다양한 환경에 의한 열화에 의해 낮은 인열강도를 나타내고 반복 열화에 따라 전기적 특성과 기계적 강도가 급격히 저하하는 단점을 가지고 있다.(중략)

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2012.04a
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• pp.480-483
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• 2012

열화원인에 의한 누전차단기 절연재료의 소손특성을 확인하기 위해서 전기적인 트래킹 열화에 의한 누전차단기 절연재료의 소손특성과 외부 복사열에 의한 누전차단기 절연재료의 소손특성을 비교 분석하였다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1184-1184
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• 2015

현재 XLPE 절연 케이블의 상시 운전 온도는 $90^{\circ}C$나 개발된 고내열성 절연재료의 상시운전온도는 $110^{\circ}C$로 향상되었다. 개발된 고내열성 절연재료는 XLPE 절연 케이블의 상시 운전온도($90^{\circ}C$)와 비상시운전온도($110^{\circ}C$), 고내열성 절연재료의 상시운전온도($110{\circ}C$), 비상시 운전온도($130{\circ}C$)을 바탕으로 하여 열 열화 온도와 기간이 설정되었다. 열 열화는 자연순환 건조기에서 설정된 온도와 기간 동안 수행되었고, 열 열화된 고내열성 절연재료는 Mckewon전극을 이용하여 AC파괴 시험이 진행 되었다. 파괴시험데이터는 와이블 분포함수를 이용하여 통계적으로 분석되었다.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.3
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• pp.193-199
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• 2015

Active thermography techniques have the capability of inspecting a broad range simultaneously. By evaluating the phase difference between the defected area and the healthy area, the technique indicates the qualitative location and size of the defect. Previously, the development of the defect detection method used a variety of materials and the test specimen was done. In this study, the proposed technique of lock-in is verified with artificial specimens that have different size and depth of subsurface defects. Finally, the defect detection capability was evaluated using comparisons of the phase image and the amplitude image according to the size and depth of defects.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.2
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• pp.142-147
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• 2007

In order to measure corrosion level of steel reinforcement rebar which is inside reinforced concrete structure, infrared thermographic technique was employed. Experimental test parameters were four different ambient temperatures and various levels of corrosion states (0, 1, 3, 5, 7 and 10% of weight loss). After analysis of temperature distributions of concrete surface, the amount of heat flux from the concrete surface is directly proportional to the corrosion level which is inside of concrete.

• Fire Science and Engineering
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• v.23 no.3
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• pp.17-22
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• 2009

Epoxy powder is being in use for insulation materials widely. Especially, in cause of coating insulation can be caused electrical fire and explosion by Joul's heat. This study has been compared and examined around breakdown, arc discharge, and V-t about insulation of Epoxy powder. Also, it has been researched about insulation which is cause of electrical fire and its basic data. According to temperature change, sample KS was stable before the Tg to be about $8{\sim}10%$ decrease in the breakdown test. In case of V-t and arc discharge, it had been kept up suitable characteristic. Also, in case of electrical characteristic, sample KS has excellent capacity.

• Applied Chemistry for Engineering
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• v.5 no.4
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• pp.630-636
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• 1994

The changes in adhesion interface between rubber compound and brass plated steel cord after various aging treatments were studied by using an Auger electron spectrometer and a scanning electron microscope. After thermal aging, partial oxidation and additional growth of adhesion layer were observed. The adhesion layer and brass were partially removed after humid aging. With dynamic aging the adhesion layer was destroyed and the corrosion of steel core was proceeded. The changes in adhesion interface were discussed in terms of the adhesion properties determined from the stress-strain experiments.

• Journal of the Korean Society for Nondestructive Testing
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• v.24 no.5
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• pp.525-531
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• 2004

In this paper, the concept of infrared thermography(IRT), the principle of measurement of IRT and how to set up the IR camera for the nondestructive testing are described in detail. Also, its utilization and non-destructive testing(NDT) diagnosis are reviewed. By performing the periodic non-touched WDT through the estimation of thermal patterns related with the temperature for the surface targeted, IRT can be applied to the early prevention of the device failure. For the diagnosis utilization, thermal imaging patterns obtained from IRT for heated blocks with internal defects were estimated through the lion-destructive method and discussed the way of IRT estimation from the analysis of characteristics between material defects and thermal imaging patterns.

• Composites Research
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• v.35 no.2
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• pp.93-97
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• 2022

The application of infrared heating in the hot press forming of the thermoplastic composites is conducive to productivity with high-speed heating. However, high energy, high forming temperature, and high-speed heating derived from infrared heating can cause material degradation and deteriorate properties such as re-melting performance. Therefore, this study was conducted to optimize the process conditions of the hot press forming suitable for carbon fiber reinforced polyetherketoneketone(CF/PEKK) composites that are actively researched and developed as high-performance aviation materials. Specifically, the degradation mechanisms and properties that may occur in infrared high-speed heating were evaluated through morphological and thermal characteristics analysis and mechanical performance tests. The degradation mechanism was analyzed through morphological investigation of the crystal structure of PEKK. As a result, the size of the spherulite decreased as the degradation progressed, and finally, the spherulite disappeared. In thermal characteristics, the melting temperature, crystallization temperature and heat of crystallization tend to decrease as degradation progresses, and the crystal structure disappeared under long-term exposure at 460℃. In addition, the low bonding strength was observed on the degraded surface, and the bonding surfaces of PEKK did not melt intermittently. In conclusion, it was confirmed that the CF/PEKK composite material degraded at 420℃ in the infrared high-speed heating. Furthermore, the spherulite experienced morphological changes and the re-melting properties of thermoplastic materials were degraded.

• Journal of Korea Far Infrared Association
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• s.37
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• pp.34-37
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• 2008