• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2002년도 춘계학술대회 논문집
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• pp.29-34
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• 2002

[ $Nb/MoSi_2-ZrO_2$ ] laminate composites have been successfully fabricated by alternately stacking $MoSi_2-ZrO_2$ powder layer and Nb sheet, followed by hot pressing in a graphite mould. The fabricating parameters were selected as hot press temperatures. The instrumented Charpy impact test was carried out at the room temperature in order to investigate the relationship between impact properties and fabricating temperatures. The interfacial shear strength between $MoSi_2-ZrO_2$ and Nb, which is associated with the fabricating temperature and the growth of interfacial reaction layer, is also discussed. The plastic deformation of Nb sheet and the interfacial delamination were macroscopically observed. The $Nb/MoSi_2-ZrO_2$ laminate composites had the maximum impact value when fabricated at 1623K, accompanying the increase of fracture displacement and crack propagation energy. The interfacial shear strength of $Nb/MoSi_2-ZrO_2$ laminate composites increased with the growth of interfacial reaction layer, which resulted from the increase of fabricating temperature. there is an appropriate interfacial shear strength for the enhancement of impact value of $Nb/MoSi_2-ZrO_2$ laminate composites. A large increase of interfacial shear strength restrains the plastic deformation of Nb sheet.

• Korea-Australia Rheology Journal
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• 제13권3호
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• pp.125-130
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• 2001

Block copolymers of PC-b-PMMA (polycarbonate-b-polymethylmethacrylate) and PC -b-SAN (polycarbonate-b-(styrene-c-acrylonitrile)), were examined as compatibilizers for blonds of PC with SAN copolymer. The average diameter of the dispersed particles was measured with an image analyser, and the interfacial properties of the blonds were analysed with an imbedded fiber retraction (IFR) technique. The average diameter of dispersed particles and interfacial tension of the PC/SAN blends reached a minimum value when the SAN copolymer contained about 24 wt% AN. Interfacial tension and particle size were further reduced by adding compatibilizer to the PC/SAN blends. PC-b-PMMA was more effective than PC-b-SAN as a compatibilizer in reducing the average diameter of the dispersed particles and interfacial tension of PC/SAN blend. A direct proportionality between the particle diameter and interfacial tension was also observed. The interfacial properties of the PC/SAN blends were optimized by adding a block copolymer and using an SAN copolymer that had minimum interaction energy with PC.

• 대한기계학회논문집A
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• 제26권7호
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• pp.1384-1392
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• 2002

Single fiber pull-out technique has been commonly used to characterize the mechanical behavior of interface in fiber reinforced composite materials. An improved analysis considering the effects of transversely isotropic properties of fiber and the effects of thermal residual stresses in both radial and axial directions along the fiber/matrix interface is developed for the single fiber pull-out test. Although the stress transfer properties across the interface is not much affected by considering the transversely isotropic properties of fiber, interfacial debonding is notably encouraged by the effect. The interfacial shear stress that plays an important role in interfacial debonding is very much affected by the component of axial thermal residual stress in the bonded region, which can induce a two-way debonding mechanism.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 일렉트렛트 및 응용기술
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• pp.53-57
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• 2002

Reduction of insulation thickness would be beneficial not only for increasing the cable length but would also improve its thermal performance. An interfacial diffusion method was devised to reduce insulation thickness by improving the interfacial properties of XLPE cable insulation. In this paper, to evaluate superficially the interface properties between XLPE insulation and semiconducting layer, the dielectric and insulation properties of tan${\delta}$ and volume resistance were measured with temperature dependence. Above the results, dielectirc and insulation properties with semiconductor/XLPE were more anormal than its bulk caused by the interfacial properties.

• 한국염색가공학회지
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• 제29권2호
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• pp.77-85
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• 2017

The interfacial adhesion between fiber and matrix affects the physical properties of fiber reinforced composites. In this study, 3-(Methacryloyloxy)propyltrimethoxy silane(MPS) coupling agent was used to increase the interfacial adhesion between polyketone fiber and epoxy resin. The change of surface chemical composition of polyketone fiber treated with MPS was analyzed using a FTIR-ATR. The interfacial bonding between fiber and resin increased with silane coupling agent largely. Consequently, interfacial shear strength(IFSS) was enhanced with increasing concentration of MPS coupling agent and thus, the physical properties of the composites such as flexural properties and dynamic mechanical properties were changed. Flexural strength and modulus increased when the MPS concentration was higher than 0.5wt%. The dynamic storage modulus of Polyketone/Epoxy composites treated with MPS was higher than that of the untreated one. When the MPS concentration of 3wt%, the highest storage modulus was obtained.

• 한국건설순환자원학회논문집
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• 제8권4호
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• pp.537-544
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• 2020

Interfacial transition zone (ITZ)은 골재-시멘트 복합체 사이의 영역으로써, 콘크리트에서 가장 취약한 영역으로 알려져 있으며, 이는 점진적으로 변화하는 불균질한 상으로 이루어져 있다. 경량 고강도 콘크리트 개발을 위해 물-바인더 비가 낮은 고강도 시멘트 복합체와 경량골재 사이의 Interfacial transition zone (ITZ)의 역학적 특성 평가는 필수적이다. 하지만 ITZ는 복잡하고 다공성 구조를 가지고 있기 때문에, 이의 역학적 특성은 아직 명확하지 않다. 또한, 경량골재 ITZ는 일반골재보다 다양한 변수 (물-바인더 비, 골재의 흡수율, 양생조건 등)에 의해 변화한다. 따라서 본 연구에서 골재의 종류 및 크기에 따른 ITZ의 역학적 특성을 분석하고자 한다. 이를 위해 나노 인덴테이션 기법을 이용하여 물-바인더 비가 0.2인 고강도 시멘트 복합체와 표준사 및 최대치수가 각각 2mm, 5mm인 경량골재 ITZ의 탄성계수를 측정하였다.

• Carbon letters
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• 제19권
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• pp.32-39
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• 2016

In this work, we studied the effects of electrochemical oxidation treatments of carbon fibers (CFs) on interfacial adhesion between CF and epoxy resin with various current densities. The surface morphologies and properties of the CFs before and after electrochemical-oxidation-treatment were characterized using field emission scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and single-fiber contact angle. The mechanical interfacial shear strength of the CFs/epoxy matrix composites was investigated by using a micro-bond method. From the results, electrochemical oxidation treatment introduced oxygen functional groups and increased roughness on the fiber surface. The mechanical interfacial adhesion strength also showed higher values than that of an untreated CF-reinforced composite.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.532-535
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• 1999

In power cable joints, the interfaces of two different dielectric materials are inevitable. In addition, the interfacial breakdown between two internal dielectric surfaces represents one of the major causes of failure for power cable joints. We chose epoxy/EPDM interface, one of the interface in cable joints, and investigate dielectric interfacial breakdown phenomenon. First, design specimen with Flux 2D. Second, find interface condition which has high dielectric strength. Third, investigate interfacial breakdown properties with variable temperature.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 추계학술발표대회 논문집
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• pp.125-128
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• 2001

In this wort, the $Na^+-MMT$ has organically modified with silane intercalant to prepare the polymer/clay nanocomposites. The pH. X-ray diffraction (XRD), and contact angles were used to analyze the surface properties of clay and the exfoliation phenomenon of clay interlayer, The mechanical interfacial properties of epoxy/clay nanocomposites were investigated by three-point bending test. From the experimental results. the surface modification made by silane intercalant on clay surface leads to an increase of distance of silicate layers, surface acid value. and electron acceptor parameter of organoclay. The treatments are also necessary and useful for epoxy to intercalate into the interlayer by interacting of electron donor-accepter between basic epoxy and clay surface. The mechanical interfacial properties of the nanocomposites was improved by the presence of dispersed clay nanolayer containing low content of organoclay in comparison with the conventional, which increase the interfacial adhesion between dispersed clay and epoxy resins.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2004년도 추계학술발표대회 논문집
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• pp.100-103
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• 2004

In this work, the effects of oxy-fluorination on surface characteristics of carbon fibers were investigated in mechanical interfacial properties of carbon fibers-reinforced composites. The surface properties of the carbon fibers were determined by X-ray photoelectron spectroscopy (XPS), FT-IR. and contact angle measurements. And their mechanical interfacial properties of the composites were studied in interlaminar shear strength (ILSS) and critical stress intensity factor $(K_{IC})$. As experimental results, the $F_{1S}/C_{1S}$ ratio of carbon fiber surfaces was increased by oxy-fluorination, due to the development of the oxygen containing functional groups. The mechanical interfacial properties of the composites, including ILSS and $K_{IC}$, had been improved in the oxy-fluorination on fibers. These results could be explained that the oxy-fluorination was resulted in the increase of the adhesion between fibers and matrix in a composite system.