• Journal of Adhesion and Interface
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• v.12 no.3
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• pp.94-98
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• 2011

Ballistic property of Heracron/phenol composites was evaluated as a function of polyurethane (PU) type and their loadings. First, prepregs of phenol and polyurethane were prepared by spray coating on Heracron fabric and then they were utilized to prepare composite by varying their ratio. Next, they were consolidated at $150^{\circ}C$ for 25 min at $150kg/cm^2$ pressure and then ballistic property was measured with 1.1 g FSP (22 cal). V50 was evaluated interms of polyurethane type and ratio of phenol/PU prepreg.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.4 s.97
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• pp.13-18
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• 1999

섬유강화금속적층재(Fiber Reinforced Metal Laminates. FRMLs)는 고강도금속과 섬유강화복합재료(Fiber Reinforced Composite Materials)를 적층한 새로운 종류의 하이브리드 재료이다. 국산 아라미드 섬유인 헤라크론(Heracron, 코오롱)과 국내 복합재료 제작기술(한국화이바)을 사용하여 섬유강화금속적층재를 제작하고, 이를 HERALL(Heracron Reinforced Aluminum Laminate)이라 명명하였다. HERALL(Heracron Reinforced Aluminum Laminate)의 피로균열성장특성 및 피로균열진전 방해기구를 ARALL(Aramid-fiber Reinforced Aluminum alloy Laminates) 및 Al 2024-T3과 비교해석하였다. HERALL과 ARALL은 균열진전을 저지하는 아라미드 섬유로 인해 뛰어난 피로균열성장특성 및 피로저항성을 보여주었다. 아라미드 섬유의 균열브리드징으로 인한 $K_{max}$의 감소량과 Al 2024-T3의 균열닫힘으로 인한 $K_{max}$의 증가량을 구할 수 있는 응력-COD법을 사용하여 실제로 균열성장에 영향을 준 유효응력확대계수범위를 측정하였다. 균열선단으로부터 균열을 가공하면서 COD 변화량을 측정하여 균열브리징 영역을 구하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.908-912
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• 1996

FRMLs consist of thin sheets of high strength metal, which are laminated using a structural adhesive and high strength fibers. ARALL(Aramid-fiber Reinforced Aluminum alloy Laminates) of FRMLs is a new class of hybrid material. HERALL(Heracron Reinforced Aluminum Laminate) i.e. domestic ARALL is made of homemade aramid fibers, adhesives and adhesive technique. Domestic aramid fiber is Heracron manufactured by KOLON and domestic adhesive is epoxy resin manufactured by Han Kuk Fiber. In this study, Fatigue crack propagation behavior was examined in a 2024-T3 aluminum alloy/aramid-fiber epoxy 3/2 laminated composites, HERALL and ARAL $L^{ⓡ}$-2 LAMINATE comparing with 2024-T3 aluminum alloy. The extrinsic toughening mechanisms in HERALL and ARALL were examined, the crack bridging behavior of fibers was analyzed by new algorithm, which measures crack bridging stress, and the crack bridging zone length was measured.

• Composites Research
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• v.32 no.2
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• pp.120-126
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• 2019

Advanced fiber fabrics have been utilized in not only anti-stabbing and bullet-proofing for body armor but also various industrial fields including vehicular armor and spacecraft structure. Furthermore, there have been a number of research to improve the ballistic performance of advanced fabrics introducing many computational approaches. In our research, an advanced fabric, Heracron manufactured in South Korea was modelled firstly using Autodyn, a commercial software specializing in impact and explosion phenomenon. The sensitivity of the input parameters was also confirmed by conducting simulations. To verify the numerical modelling, we measured and compared the simulation results with velocity decrements after impact involving one, three, and five layers of Heracron under 200-500 m/s impacts by an aluminum spherical projectile. The Heracron fabric was successfully modelled using Autodyn.