• 한국산학기술학회논문지
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• 제5권3호
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• pp.218-222
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• 2004

본 연구에서는 분리형 이동코어 방식의 스탬퍼 금형을 개발하였고, 사출성형품 품질에 영향을 주는 인자 중에 이동코어 표면 가열 방식이 미세구조를 갖는 성형품 전사성에 미치는 영향에 대해 알아보았다. 이동코어 표면 가열방식은 이동코어를 가열하지 않는 일반사출방식, 할로겐램프를 이용한 복사형 가열방식과 기체화염을 이용해 가열하는 MmSH 방식을 사용했다. COC, PMMA 두 종류의 열가소성 수지를 사용하여 성형품을 제작한 결과, 이동코어 표면온도가 가장 높은 MmSH 방식에서 나노패턴 전사성이 가장 우수했고, 일반사출성형 방식으로 제작한 성형품에서 전사성이 가장 저조했다.

• 비파괴검사학회지
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• 제37권2호
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• pp.91-98
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• 2017

Recently, composite materials have been mainly used in the main wings, ailerons, and fuselages of aircraft and rotor blades of helicopters. Composite materials used in rapid moving structures are subject to impact by hail, lightning, and bird strike. Such an impact can destroy fiber tissues in the composite materials as well as deform the composite materials, resulting in various problems such as weakened rigidity of the composite structure and penetration of water into tiny cracks. In this study, experiments were conducted using a 2 kW halogen lamp which is most frequently used as a light source, a 2 kW near-infrared lamp, which is used for heating to a high temperature, and a 6 kW xenon flash lamp which emits a large amount of energy for a moment. CFRP composite sandwich panels using Nomex honeycomb core were used as the specimens. Experiments were carried out under impact damages of 1, 4 and 8 J. It was found that the detection of defects was fast when the xenon flash lamp was used. The detection of damaged regions was excellent when the halogen lamp was used. Furthermore, the near-infrared lamp is an effective technology for showing the surface of a test object.