• Title, Summary, Keyword: interfacial shear strength

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A Study on the Improvement of Interfacial Bonding Shear Strength of Ti50-Ni50 Shape Memory Alloy Composite (Ti_{50}-Ni_{50} 형상기억합금 복합체의 계면 접학 전단강도 향상에 관한 연구)

  • Lee, Hyo-Jae;Hwang, Jae-Seok
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.10
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    • pp.2461-2468
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    • 2000
  • In this paper, single fiber pull-out test is used to measure the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory alloy composite with temperature. Fiber and matrix of $Ti_{50}-Ni_{50}$ shape memory alloy composite are respectively $Ti_{50}-Ni_{50}$ shape memory alloy and epoxy resin. To strengthen the interfacial bonding shear stress, various surface treatments are used. They are the hand-sanded surface treatment, the acid etched surface treatment and the silane coupled surface treatment etc.. The interfacial bonding shear strength of surface treated shape memory alloy fiber is greater than that of surface untreated shape memory alloy fiber by from 10% to 16%. It is assured that the hand-sanded surface treatment and the acid etched surface treatment are the best way to strengthen the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory composite. The best treatment condition of surface is 10% HNO$_3$ solution in the etching method to strengthen the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory alloy composite.

A novel hemispherical microbond specimen for evaluating the interfacial shear strength of single fiber composite (복합재료의 계면 전단강도를 평가하기 위한 새로운 반구형 미소접합 시험편)

  • Park, Joo-Eon;Choi, Nak-Sam
    • Composites Research
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    • v.21 no.2
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    • pp.25-30
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    • 2008
  • A hemispherical microbond specimen adhered onto single carbon fiber has been proposed for evaluating the interfacial shear strength between epoxy and carbon fiber. Hemispherical microbond specimens showed low interfacial shear strength data and its small standard deviation as compared with the droplet one, which seemed to be caused by the reduction of the meniscus effects and of the stress concentration in the region contacting with the tip of pin hole. In comparison with the droplet specimen the hemispherical specimen showed the shear stress distribution similar to the cylindrical one in that low stress concentration arose around the contacting region. Average interfacial shear strength obtained by the hemispherical ones represented a good correlation with the hardness of the epoxy matrix.

Change of Interfacial properties by the Fiber Degradation in the Fiber Reinforced Composites (섬유강화 복합재료에서 섬유열화에 따른 계면특성의 변화)

  • Moon, Chang-Kwon;Kim, Young-Dae;Roh, Tae-Young
    • Journal of Ocean Engineering and Technology
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    • v.12 no.3
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    • pp.31-41
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    • 1998
  • Single fiber fragmentation technique was used to evaluate the change of interfacial properties by degradation of fiber tensile strength in the fiber reinforced composites. The influences of fiber tensile strength on the interfacial properties have been evaluated by the fragmentation specimens(weak fiber samples) of glass fiber/epoxy resin that was made using the pre-degraded glass fiber in distilled water at $80^{circ}C$ for specified periods. The effects of the immersion time on the interfacial properties in the distilled water at $80^{circ}C$ also have been evaluated by the fragmentation specimens(original fiber samples) of glass fiber/epoxy resin that was made using the received glass fiber. As the result, the tensile strength of glass fiber was decreased with the increasing of the treatment time in the distilled water at $80^{circ}C$ and the interfacial shear strength was independent of the change of the glass fiber strength in the single fiber fragmentation test. But in the durability test using the single fiber fragmentation specimen, interfacial shear strength decreased with the increasing of the immersion time in distilled water ar $80^{circ}C$. And it turned out that the evaluating of interfacial shear strength using original fiber tensile strength was valuable in the durability test for the water environment by the single fiber fragmentation technique.

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Impact Fracture and Shear Strength Characteristics on Interfacial Reaction Layer of Nb/MoSi2 Laminate Composite

  • Lee, Sang-Pill;Yoon, Han-Ki;Park, Won-Jo
    • International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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    • v.3 no.1
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    • pp.35-39
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    • 2000
  • The present study dealt with the relationships among the interfacial shear strength, the thickness of interfacial reaction layer and the impact value of $Nb/MoSi_2$ laminate composites. In addition, the tensile test was conducted to evaluate the fracture strain of $Nb/MoSi_2$ laminate composites. To change the thickness of the reaction layer, $Nb/MoSi_2$ laminate composites alternating sintered MoSi2 layers and Nb foils were fabricated as the parameter of hot press temperature. It has been found that the growth of the reaction layer increases the interfacial shear strength and decreases the impact value by localizing a plastic deformation of Nb foil. There also exist appropriate shear strength and the thickness of the reaction layer, which are capable of maximizing the fracture energy of $Nb/MoSi_2$.

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Fabrication and Fracture Properties of Nb/MoSi2Laminate Composites (Nb/MoSi2적층복합재료의 제조 및 파괴특성)

  • Lee, Sang-Pill;Yoon, Han-Ki
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.6
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    • pp.1047-1052
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    • 2002
  • The impact value, the interfacial shear strength, the tensile strength and the fracture strain of Nb/MoSi$_2$laminate composites, which were associated with the interfacial reaction layer, have been investigated. Three types of Nb/MoSi$_2$ laminate composites alternating sintered MoSi$_2$ layers and Nb foils were fabricated as the parameter of hot press temperature. The thickness of interfacial reaction layer of Nb/MoSi$_2$ laminate composites increased with increasing the fabrication temperature. The growth of interfacial reaction layer increased the interfacial shear strength and led to the decrease of impact value in Nb/MoSi$_2$ laminate composites. It was also found that in order to maximize the fracture energy of Nb/MoSi$_2$ laminate composites, interfacial shear strength and the thickness of interfacial reaction layer must be secured appropriately.

Fabrication and Impact Properties of $Nb/MoSi_2-ZrO_2$ Laminate Composites ($Nb/MoSi_2-ZrO_2$ 적층복합재료의 제조 및 충격특성)

  • Lee, Sang-Pill;Yoon, Han-Ki;Kong, Yoo-Sik
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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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.

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Effects of electrochemical oxidation of carbon fibers on interfacial shear strength using a micro-bond method

  • Kim, Dong-Kyu;An, Kay-Hyeok;Bang, Yun Hyuk;Kwac, Lee-Ku;Oh, Sang-Yub;Kim, Byung-Joo
    • Carbon letters
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    • v.19
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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.

Statistical Analysis of Interfacial Shear Strength on Fiber-Matrix (섬유-Matrix의 계면전단강도에 관한 통계적고찰)

  • 문창권;남기우;엄윤성
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.2
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    • pp.200-206
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    • 1992
  • The effect of fiber diameter and gauge length on pull-out test for the interfacial properties in fiber reinforced resin composites have been investigated and these results have been arranged as statistical analysis. The fiber and matrix resins used for this study were stainless steel fiber (SUS316) and carbon fiber (high strength type), epoxy and high density polyethylene resin. From this study, it has been found that shear strength are constant regardless of gauge length of pull-out test and coefficient of variation depend on fiber diameter. In addition, it has been found that the interfacial shear strength decreased with the increasing fiber diameter, and in all case, Weibull parameter (m) has approximately 1.2/C.O.V.

Study on Degradation and Recovery of Interfacial Strength in the Aqueous Environment (수분환경에서 계면강도의 열화 및 회복에 관한 연구)

  • 김영운;김윤석;문창권
    • Textile Science and Engineering
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    • v.38 no.3
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    • pp.123-129
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    • 2001
  • In this study a fragmentation test has been carried out to investigate moisture gain as a function of immersion time for durability test in various aqueous environments such as tap water, sea water, and distilled water at room temperature and 8$0^{\circ}C$. The correlation of the variation of moisture gain induced by immersion and drying after immersion in distilled water at 8$0^{\circ}C$ with the interfacial shear strength between carbon fiber and epoxy resin has been then investigated. As a result, very similar values of moisture gain were obtained for the various aqueous environments such as sea water, tap water, and distilled water at room temperature. However, at 8$0^{\circ}C$, the weight gain was found to be highest for sea water and lowest for distilled water. For specimens weight gain does not mean the moisture gain. We also found that interfacial shear strength of the specimen immersed at 8$0^{\circ}C$ decreased with the increase of moisture gain and interfacial shear strength of the specimens immersed for 30,l 60, and 90 days was recovered up to about 60~75% of the initial value by drying for 60 days at room temperature.

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Interfacial Shear Strength and Thermal Properties of Electron Beam-Treated Henequen Fibers Reinforced Unsaturated Polyester Composites

  • Pang Yansong;Cho Donghwan;Han Seong Ok;Park Won Ho
    • Macromolecular research
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    • v.13 no.5
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    • pp.453-459
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    • 2005
  • Natural fiber henequen/unsaturated polyester (UPE) composites were fabricated by means of a compression molding technique using chopped henequen fibers treated at various electron beam (EB) dosages. The interfacial shear strength (IFSS), dynamic mechanical properties, and thermal expansion behavior were investigated through a single fiber microbonding test, fractographic observation, dynamic mechanical analysis, and thermomechanical analysis, respectively. The results indicated that the interfacial and dynamic mechanical properties significantly depended on the level of the EB treatment irradiated onto the henequen fiber surfaces. The effect of EB treatment on the IFSS, storage modulus and fracture surface of the henequen/UPE composites agreed with each other. The results of this study also suggested that the modification of henequen fiber surfaces at 10 kGy EB is the most effective for improving the interfacial properties of the henequen/UPE composites.