• 제목/요약/키워드: amorphous metallic fiber

검색결과 17건 처리시간 0.024초

비정질 강섬유 보강 시멘트 복합체의 전자파 차폐성능 평가 (Evaluation of Electromagnetic Pulse Shielding Performance of Amorphous Metallic Fiber Reinforced Cement Composite)

  • 이상규;김규용;황의철;손민재;백재욱;남정수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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    • pp.50-51
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    • 2018
  • In this study, it evaluate the electromagnetic pulse shielding performance of amorphous metallic fiber reinforced cement composite with other steel fiber reinforced cement composite. Hooked-ended steel fiber, smooth steel fiber and amorphous metallic fiber were reinforced 2.0 vol.% in cement composites respectively. The electromagnetic pulse shielding performance was evaluated by MIL-STD-188-125-1. As a result, shielding performance of amorphous metallic fiber reinforced cement composite was higher than Hooked-ended and smooth steel fiber reinforced cement composites. In addition, the relationship between the electrical conductivity and the electromagnetic pulse shielding performance of the cement composite was confirmed.

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비정질 강섬유보강 시멘트복합체의 정역학특성 및 내충격성능 평가를 통한 구조물 적용 가능성 검토 (Investigation on the Applicability of Structures by Evaluating the Static Properties and the Impact Resistance Performance of Amorphous Metallic Fiber Reinforced Cement Composites)

  • 강일수;김규용;이보경;이상규;손민재;남정수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 추계 학술논문 발표대회
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    • pp.79-80
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    • 2017
  • This study examined the effect that the amorphous metallic fibers had on the static mechanical properties and the impact resistance of cement composites to those of hooked steel fibers. The hooked steel fiber exhibited pull-out from the matrix after the peak flexural stress was attained, while the amorphous metallic fiber was not pulled out from the matrix, but was instead cut off. In terms of impact resistance, the amorphous metallic fiber reinforced cement composite was found to be more effective at resisting cracking than the hooked steel fiber reinforced cement composite. Therefore, amorphous metallic fiber should be used in fiber reinforced cement composite materials, and for structural materials, and for protection panels.

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비정질금속섬유 혼입율에 따른 시멘트 경화체의 강도 특성 (Strength Properties of Cement Composite according to the Mixing Ratio of Amorphous Metallic Fiber)

  • 김지환;노영환;이재인;배성호;오태규;최세진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2020년도 가을 학술논문 발표대회
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    • pp.79-80
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    • 2020
  • This study compared and analyzed the flow and strength characteristics of cement paste according to the rate of mixing of amorphous metallic fiber as part of the research for the development of amorphous metallic fiber reinforced cement composite.

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비정질강섬유 보강 고강도 콘크리트의 온도별 잔존 역학적 특성 평가 (The residual mechanical properties evaluation according to temperature of the amorphous metallic fiber reinforced high strength concrete)

  • 서동균;김규용;이상규;황의철;유하민;남정수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2020년도 가을 학술논문 발표대회
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    • pp.98-99
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    • 2020
  • This study is aim to assess mechanical properties which is highly related to structural safe and durability of 100MPa high strength concrete mixed with amorphous metallic fiber. All specimens were heated with low velocity heating rate(1℃/min.), residual compressive strength and residual flexural strength was evaluated. The specimens were cooled down to room temperature after heating. As a result, in the case of 100MPa high-strength concrete, the residual compressive strength enhancing effect of amorphous metallic fiber has showed with the mix proportion of fiber. In addition, residual flexural strength showed more regular pattern before 300℃ then residual compressive strength, but simillar decreasing behavior was shown after 300℃ like residual compressive strength. Further study about fiber pull-out behavior and fiber mechanical, chemical property change due to temperature is needed.

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섬유길이에 따른 비정질 강섬유 보강 시멘트 복합체의 충격파괴특성 (Impact Fracture Properties of Amorphous Metallic Fiber Reinforced Cementitious Composite by Fiber Length)

  • 이상규;김규용;황의철;손민재;편수정;남정수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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    • pp.65-66
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    • 2019
  • In this study, flexural strength and impact resistance were evaluated to investigate the fiber length effect of amorphous metallic fiber. As a result, in the case of 30AFRCC, cutoff behavior due to excellent bonding performance by large specific surface area has greatly influence on the flexural and impact resistance performance. In the case of 15AFRCC, the bonding efficiency is relatively low, because the specific surface area is smaller than that of 30AFRCC and the number of fiber is large, so the effect of improving the flexural and impact resistance performance is smaller than that of 30AFRCC.

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섬유 종류에 따른 섬유 보강 시멘트 복합체의 전기적 특성에 대한 실험적 연구 (Correlation between Electrical Conductivity and Shielding Effectiveness of Cementitous Composites according to Length and Volume Fraction of Steel Fiber)

  • 이예찬;김규용;한승현;최윤성;김문규;남정수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 봄 학술논문 발표대회
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    • pp.183-184
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    • 2023
  • The purpose of this study is to compare and analyze the effect of type and volume fraction of fiber on the electrical conductivity and shielding effectiveness of cementitious composites. The large specific surface area of amorphous metallic fiber, as well as the high number of fibers per unit weight, provided an advantage in the formation of conductive path. As the result, the electrical conductivity of amorphous metallic fiber was evaluated to be higher, and the shielding effectiveness was also higher. However, the shielding effectiveness according to electrical conductivity was confirmed to have a threshold point, and further research is needed to improve it.

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Mechanical Properties and Modeling of Amorphous Metallic Fiber-Reinforced Concrete in Compression

  • Dinh, Ngoc-Hieu;Choi, Kyoung-Kyu;Kim, Hee-Seung
    • International Journal of Concrete Structures and Materials
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    • 제10권2호
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    • pp.221-236
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    • 2016
  • The aim of this paper is to investigate the compressive behavior and characteristics of amorphous metallic fiber-reinforced concrete (AMFRC). Compressive tests were carried out for two primary parameters: fiber volume fractions ($V_f$) of 0, 0.3, 0.6 and 0.8 %; and design compressive strengths of 27, 35, and 50 MPa at the age of 28 days. Test results indicated that the addition of amorphous metallic fibers in concrete mixture enhances the toughness, strain corresponding to peak stress, and Poisson's ratio at high stress level, while the compressive strength at the 28-th day is less affected and the modulus of elasticity is reduced. Based on the experimental results, prediction equations were proposed for the modulus of elasticity and strain at peak stress as functions of fiber volume fraction and concrete compressive strength. In addition, an analytical model representing the entire stress-strain relationship of AMFRC in compression was proposed and validated with test results for each concrete mix. The comparison showed that the proposed modeling approach can properly simulate the entire stress-strain relationship of AMFRC as well as the primary mechanical properties in compression including the modulus of elasticity and strain at peak stress.

비정질금속섬유 보강 자기치유 모르타르의 역학 및 내구특성 (Mechanical and Durability Characteristics of Amorphous Metallic Fiber Reinforced Self-Healing Mortar)

  • 윤주호;이민욱;김채영;이재인;최세진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 가을학술발표대회논문집
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    • pp.27-28
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    • 2023
  • This study compared and analyzed the fluidity, compressive strength, and carbonation resistacne of amorphous metal fiber reinforced mortar according to the PCC mixing ratio as part of a study to improve the self-healing performance and tensile performance of concrete structures.

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비정질 강섬유의 길이 및 혼입률에 따른 섬유보강 시멘트복합체의 직접인장특성 (Direct Tensile Properties of Fiber-Reinforced Cement Based Composites according to the Length and Volume Fraction of Amorphous Metallic Fiber)

  • 김홍섭;김규용;이상규;최경철;남정수
    • 한국건축시공학회지
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    • 제19권3호
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    • pp.201-207
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    • 2019
  • 본 연구에서는 변형속도에 따른 비정질 강섬유보강 시멘트복합체의 직접인장특성에 대하여 평가하였다. 길이 15, 30mm의 박판형 비정질 강섬유를 각각 1.0, 1.5, 2.0% 혼입한 섬유보강 시멘트복합체를 제작하였으며, 변형속도 $10^{-6}/s$(정적), $10^1/s$(동적)의 조건에서 직접인장시험을 수행하였다. 그 결과, 길이 15mm의 비정질 강섬유는 섬유의 섬유의 길이가 짧고 혼입개체수가 많기 때문에 섬유가 매트릭스로부터 인발되었다. 반면, 길이 30mm의 비정질 강섬유는 섬유의 표면이 거칠고 비표면적이 크기 때문에 매트릭스와의 부착성능이 우수하지만, 박판형의 섬유 형상이 전단력에 약하기 때문에 섬유가 인발되지 않고 파단 되었다. 섬유의 길이가 길수록 인장강도, 변형능력 및 인성이 큰 것으로 나타났다. 반면, 길이 30mm의 비정질 강섬유는 매트릭스로부터 인발되지 않고 파단 되지만 길이 15mm의 비정질 강섬유는 매트릭스로부터 인발되기 때문에 변형속도의 영향을 받는 섬유-매트릭스 계면의 부착효율이 크게 되어, 인장강도, 변형능력 및 인성에 대한 동적증가계수가 큰 것으로 나타났다.

액상가압공정으로 제조된 금속 연속섬유강화 비정질 복합재료의 미세파괴거동 (Microfracture Behavior of Metallic-Continuous-Fiber-Reinforced Amorphous Matrix Composites Fabricated by Liquid Pressing Process)

  • 이규홍;이상복;이상관;이성학
    • 대한금속재료학회지
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    • 제46권8호
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    • pp.524-537
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    • 2008
  • Zr-based amorphous alloy matrix composites reinforced with metallic continuous fibers were fabricated by liquid pressing process, and their fracture properties were investigated by directly observing microfracture process using an in situ loading stage installed inside a scanning electron microscope chamber. About 60 vol.% of metallic fibers were homogeneously distributed inside the amorphous matrix. Apparent fracture toughness of the stainless-steel- and tungsten-fiber-reinforced composites was lower than that of monolithic amorphous alloy, while that of the Ta-fiber-reinforced composite was higher. According to the microfracture observation, shear bands or cracks were initiated at the amorphous matrix, and the propagation of the initiated shear bands or cracks was effectively blocked by fibers, thereby resulting in stable crack growth which could be confirmed by the fracture resistance curve (R-curve) behavior. This increase in fracture resistance with increasing crack length improved fracture properties of the fiber-reinforced composites, and could be explained by mechanisms of formation of multiple shear bands or multiple cracks at the amorphous matrix and blocking of crack or shear band propagation and multiple necking at metallic fibers.