• Composites Research
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• v.29 no.4
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• pp.203-208
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• 2016

Metal and polymer sandwich composites, which are made of sheet metal sheath and polymer or fiber reinforced plastic core, have been reconsidered as an alternative to sheet metal due to their lightness and multifunctional properties such as damping and sound-proof properties. For the successful applications of these composites, the delamination prediction based on the adhesion strength is important element. In this study, the numerical simulation of the delamination behavior of polymeric adhesive tapes with metallic surfaces was performed using cohesive zone elements and finite element software. The traction-separation law of the cohesive zone element was defined using the fracture energy derived from peel mechanics and experimental results from peel test and implemented in finite element software. The peel test of the polymeric adhesive film against steel surface was simulated and compared with experiments, demonstrating reasonable agreement between simulation and experiment.

• Composites Research
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• v.21 no.3
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• pp.18-23
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• 2008

The Rapid Prototyping (RP) technology has advanced in many application areas. In this research, implantable Drug Delivery System (DDS) was fabricated by an RP system, Nano Composite Deposition System (NCDS). The DDS composite consists of 5-fluorouracil (5-FU), as drug particles, and PLGA85/15 as biodegradable polymer matrix. To have larger surface area, the DDS was fabricated in a scaffold shape, and its degradation was tested in vitro environment. Biocompatible Hydroxyapatite (HA) powders were added to the drug-polymer composite in order to control drug release. Test results showed a possibility of controlled release of scaffold DDS over 50 days.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.10a
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• pp.192-195
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• 2003

최근 첨단기술 집약형 자동화 시스템과 정보기술의 발달에 따라 산업은 고도화, 정밀화되고 있다. 특히 안전분야 중 기능성 고분자 재료의 응용 분야로서 carbon black, carbon fiber, graphite, 금속 분말 등의 전도성 충전재를 고분자 matrix에 혼입하여 전도성 복합재료를 성형가공하는 기술이 개발되고 있다. 이를 이용한 복합성형체는 과전류 차단, 회로 보호, 전자파 차폐효과 등의 특성을 이용한 electrical hazard 감소 효과, 제어설비, 자동화 설비, 제조설비 등 각종 산업설비의 정밀제어, 과전류차단 및 외란 방지 등에 다양한 용도로 활용되고 있다.(중략)

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.05a
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• pp.457-460
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• 2002

현재 건축단열재, 흡음재, 바닥재로 사용되는 panel 성형, 제작하기 위해 다종의 유기고분자 matrix가 사용되고 있으며 polyurethane, vinyl acetate, urea-formaldehyde resin 또는 melamine-formaldehyde, phenol-form aldehyde resin 등을 사용하고 있으나 이러한 고분자 matrix를 사용한 건축용 panel의 경우 화재시 유독 gas와 더불어 급격한 화재전파의 매개체로 사용될 수 있어 난연제 첨가로 이러한 현상을 억제하고 있다.(중략)

• Journal of the Korean Institute of Gas
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• v.25 no.2
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• pp.64-71
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• 2021

Research on polymer matrix composites with excellent molding processability and mechanical properties in the automotive field including hydrogen fuel cell electric vehicles is expanding to Computer-Aided Engineering (CAE) to support the design of materials with specific mechanical properties. CAE automation requires the prediction of the mechanical properties and behavior of materials. Unlike single materials, the mechanical properties prediction of polymer matrix composites is difficult to explain with formulas because the mechanical behavior is complicated to be explained only by the relationship between the matrix and the filler. In this study, the stress-strain curve according to the composition of polymer matrix composites, which was difficult to predict due to its sensitivity to large plastic deformation and composition, was predicted based on machine learning of the test data. The developed model finds a complex correlation between matrix and filler types and compositions, and predicts the total stress-strain curve meaningfully even in the absence of learned test data. It is expected that the material design AI system can be completed in the future based on the developed model that predicts the mechanical properties of polymer matrix composites even for the combination and composition that have not been learned.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1989.06b
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• pp.29-34
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• 1989

고분자 복합재료들은 오늘날 광범위하게 마찰 부위들에 응용되고 있다. 다양한 첨가제와 보강재들이 고분자 물질들에 넣어져 강도와 마모 특성들을 향상 시키고 있다. 예를 들어, 다양한 복합재료들로서 현재 입수 가능한 것에 베어링 재료들이 있으며 이에 포함되는 것이 자체 윤활 보강 플라스틱 들이며 이들에는 고체 윤활제, 즉, 테플톤, $MoS_2$, 혹은 흑연가루들이 첨가된다. 실험적 그리고 이론적인 연구들이 여러 조건들에서의 섬유 보강 복합 재료들의 마모 거동에 대하여 보고되었다(예를 들어, 미끄럼 마모, 연마 마모, 입자 충격 마모, 비빔 마모). Tsukizoe와 Ohmae의 보고에 의하면 탄성계수 탄소섬유 복합재료는 가장 적은 마모가 횡단 방향(Transverse)에서 있고, 고 강도 탄소 섬유 복합재료는 길이 방향(Longitudinal)에서 있다. 가장 많은 마모는, 고 탄성계수 복합재료는 길이 방향에서, 고 강도 섬유 복합재료는 횡단 방향에서 잇다. 그들이 또한 발표한 것은 양쪽의 고 탄성계수와 고 강도 섬유 복합재료들의 수직방향(Norma)에서 눌러 불음(Seizure)가 일어났다고 한다.

• Computational Structural Engineering
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• v.28 no.2
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• pp.45-51
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• 2015

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.352-353
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• 2003

Clay 분산 유/무기 나노복합재 제조기술은 실리케이트 층상구조의 점토광물을 나노 스케일의 시트상의 기본 단위로 박리(exfoliation)하여 고분자수지에 분산시킴으로써 범용 고분자의 낮은 기계적 물성의 한계를 엔지니어링 플라스틱 수준으로까지 올리고자 하는 것으로서, 기존의 무기 충진재 및 강화재의 입자크기(〉1 $\mu\textrm{m}$)를 나노 스케일까지 분산시켜 기존 무기물 충진 복합재의 단점을 한층 보완하는 것을 목표로 하고 있어 성능 및 원가 면에서 매우 유리한 방법으로 21세기의 복합재료 생산시장의 판도에 상당한 변화를 가져오게 할 수 있는 핵심기술이라 할 수 있다. (중략)

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.2
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• pp.81-85
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• 2017

Fiber-reinforced polymer composites, which are made by combining a continuous fiber that acts as reinforcement and a homogeneous polymeric material that acts as a host, are engineering materials with high strength and stiffness and a lightweight structure. In this study, a shape memory alloy(SMA) reinforced composite actuator is presented. This actuator is used to generate large deformations in single lightweight structures and can be used in applications requiring a high degree of adaptability to various external conditions. The proposed actuator consists of numerous individual laminas of the glass-fiber fabric that are embedded in a polymeric matrix. To characterize its deformation behavior, the composition of the actuator was changed by changing the matrix material and the number of the glass-fiber fabric layers. In addition, current of various magnitudes were applied to each actuator to study the effect of the heating of SMA wires on applying current.

• Composites Research
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• v.30 no.5
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• pp.316-322
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• 2017

Carbon fiber is a material with excellent mechanical, electrical and thermal properties, which is widely used as a composite material made of a polymer matrix. However, this composite material has a weak point of interlaminar delamination due to weak interfacial bond with polymer matrix compared with high strength and elasticity of carbon fiber. In order to solve this problem, it is essential to use reinforcements. Due to excellent mechanical properties, graphene have been expected to have large improvement in physical properties as a reinforcing material. However, the aggregation of graphene and the weak interfacial bonding have resulted in failure to properly implement reinforcement effect. In order to solve this problems, dispersibility will be improved. In this study, functionalization of graphene nanoplatelet was proceeded with melamine and mixed with epoxy polymer matrix. The carbon fiber reinforced polymer composites were fabricated using the prepared graphene nanoplatelet/epoxy and flexural properties and interlaminar shear strength were measured. As a result, it was confirmed that the dispersibility of graphene nanoplatelet was improved and the mechanical properties of the composite material were increased.