• 제목/요약/키워드: Interface Fracture

검색결과 523건 처리시간 0.022초

이종접합 계면균열의 파괴기준에 대한 원공의 영향 (Influence of Circular Hole for Fracture Criteria of Interface Crack in Bonded Dissimilar Materials)

  • 정남용
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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    • pp.301-306
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    • 1999
  • Application of bonded dissimilar materials in various industries are increasing. When these materials are used in structures, it needs to investigate strength evaluation applying fracture mechanics. Al/Epoxy bonded dissimilar materials with an interface crack and an interface crack emanating from an edge semicircular hole were prepared for the static tests so that experiment of fracture toughness were carried out. Stress intensity factors of interface cracks in bonded dissimilar materials were computed with boundary element method(BEM) and the fracture criteria of mixed mode crack were analyzed. From the results, the fracture criteria and the method of strength evaluation by the fracture toughness in Al/ Epoxy bonded dissimilar materials were proposed.

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이종 접합부재의 계면균열 파괴인성의 평가 (Evaluation of Fracture Toughness on Interface Cracks in Bonded Components of Dissimilar Materials)

  • 정남용;이명대;박철희
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.346-351
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    • 2003
  • In this paper, an evaluation method of fracture toughness on interface cracks has been investigated under various mixed-mode conditions of the bonded scarf joints. Two types of the bonded scarf joints with an interface crack were prepared to analyze the stress intensity factors using boundary element method(BEM) and to perform the fracture toughness test. From the results of fracture toughness experiments and BEM analysis, an evaluation method of fracture toughness on interface cracks in the bonded components of dissimilar materials has been proposed and discussed.

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이종 마찰용접재의 계면균열에 대한 파괴인성의 평가방법 (An Evaluation Method of Fracture Toughness on Interface Crack in Friction Welded Dissimilar Materials)

  • 정남용;박철희
    • 한국자동차공학회논문집
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    • 제15권4호
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    • pp.171-177
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    • 2007
  • In this paper, an evaluation method of fracture toughness on interface cracks was investigated in friction welded dissimilar materials with interfacial edge cracks. To establish a reasonable strength evaluation method and fracture criterion, it is necessary to analyze stress intensity factor under the load and residual stress condition on friction welded interface between dissimilar materials. The friction welded specimens with an edged crack were prepared for analysis of stress intensity by using the boundary element method (BEM) and the fracture toughness. A quantitative fracture criterion for friction welded STS 304/SM 45C with interface crack is suggested by using stress intensity factor, F and the results of fracture toughness experiment.

이종 접합체의 계면균열에 대한 파괴인성의 평가방법 (An Evaluation Method of fracture Toughness on Interface Cracks in Bonded Dissimilar Materials)

  • 정남용
    • 한국자동차공학회논문집
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    • 제11권4호
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    • pp.110-116
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    • 2003
  • In this paper, an evaluation method of fracture toughness on interface cracks has been investigated under various mixed-mode conditions of the bonded scarf joints. Two types of the bonded scarf joints with an interface crack were prepared to analyze the stress intensity factors using boundary element method(BEM) and to perform the fracture toughness test. From the results of fracture toughness experiments and BEM analysis, an evaluation method of fracture toughness on interface cracks in the bonded dissimilar materials has been proposed and discussed.

이종 접합체에 대한 혼합모드 파기기준의 설정 (Establishment of fracture Criterion for Mixed Mode in Bonded Dissimilar Materials)

  • 정남용
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1998년도 추계학술대회 논문집
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    • pp.254-260
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    • 1998
  • Application of bonded dissimilar materials in various industries are increasing. When these materials are used in structures, it needs to investigate strength evolution applying fracture mechanics. Al/Epoxy bonded dissimilar materials with an interface crack and an interface crack emanating from an edge semicircular hole were prepared for the static tests so that experiment of fracture toughness were carried out. Stress intensity factors of interface cracks in bonded dissimilar materials were computed with boundary element method(BEM) and the fracture criterion of mixed mode crack were analyzed. From the results, the fracture criterion and the method of strength evolution by the fracture toughness in Al/Epoxy bonded dissimilar materials were proposed.

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이종 접합체의 원공에서 파생하는 균열에 대한 혼합모드 파괴기준의 설정 (Establishment of Fracture Criteria for Mixed Mode in Bonded Dissimilar Materials with an Crack Emanating from an Edge Semicircular Hole)

  • 정남용;송춘호
    • 대한기계학회논문집A
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    • 제25권6호
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    • pp.907-915
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    • 2001
  • Application of bonded dissimilar materials in many industries are increasing. When these materials are to be used in structures, it needs to evaluate the failure strength applying fracture mechanics. Al/Epoxy bonded dissimilar materials with an interface crack and an interface crack emanating from an edge semicircular hole were prepared, experiment of fracture toughness were carried out. Stress intensity factors of interface cracks in bonded dissimilar materials were computed with boundary element method(BEM) and the fracture criteria of mixed mode crack were analyzed. From the results, the fracture criteria and the method of strength evaluation by the fracture toughness in Al/Epoxy bonded dissimilar materials were proposed.

$ZrO_2/NiTi$ 접합부 반응조직에 따른 꺽임강도 및 파괴거동 변화 (The Variation of Fracture Strength and Modes in $ZrO_2/NiTi$ Bond by Changing Reaction Layer)

  • 김영정
    • 한국세라믹학회지
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    • 제31권10호
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    • pp.1197-1201
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    • 1994
  • The fracture strength and fracture modes were studied in 3Y-TZP/NiNi bonding which change their interfacial structure with bonding condition. Average 4-point bending strength of 200 MPa to 400 MPa were achieved. The formation of Ti-oxide phase at the interface critically influenced the bonding strength and fracture mode. The fracture surface of Ti-oxide free interface contained multiphase in some case including ZrO2. From the result it was confirmed that in order to maximize the bonding strength crack deflection from interface to ceramic was required.

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세라믹스/금속 접합계면에서의 파괴력학적 강도평가에 관한 연구 (A study on the Fracture Mechanical Strength Evaluation in Joint Interface of Ceramics and Metal)

  • 최병기
    • 한국안전학회지
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    • 제11권3호
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    • pp.20-24
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    • 1996
  • Indentation fracture method and 4-point bending test are carried out to measure the residual stresses and the bending strength, and to investigate the mechanism of fracture mechanics in the bonded interface of ceramic and metal. The results obtained are as follows ; 1) The fracture patterns of bonded materials shows that the delamlnatlon fracture of Interfaces is stablely developed from the interfaces of ceramic/active metallic bonded materials at the specimen center, and the fracture is unstablely generated through a refraction on the middle ceramic. 2) Distribution of residual stresses is quantitatively investigated on the ceramic side of bonded materials. 3) It Is found that the residual stresses of interface vertical direction are concentrated on the bonded interface at the ceramic side.

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에너지 방출률에 의한 접착이음의 계면균열에 대한 파괴인성의 평가 (Evaluation of Fracture Toughness by Energy Release Rate for Interface Crack in Adhesively Bonded Joints)

  • 정남용;이명대;강삼근
    • 대한기계학회논문집A
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    • 제24권9호
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    • pp.2174-2183
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    • 2000
  • In this paper, the evaluation method of interfacial fracture toughness to apply the fracture toughness was investigated in adhesively bonded joints of AI/Ced./A1. Four types of adhesively bonded double-cantilever beam(DCB) joints with the interface crack were prepared for the test of interfacial fracture toughness. The experiments to measure the interfacial fracture toughness were performed under the various mixed-mode conditions. The critical energy release rate, Gc, was obtained by the experimental measurement of compliances. From the experimental results, the interfacial fracture toughness for the mixed-mode specimens is well characterized by the energy release rate, and the method of strength evaluation by the interfacial fracture toughness was discussed in adhesively bonded joints.

콘크리트의 계면 파괴와 균열 전파 : 파괴규준과 수치모의 (Interface Fracture and Crack Propagation in Concrete : Fracture Criteria and Numerical Simulation)

  • 이광명
    • 콘크리트학회지
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    • 제8권6호
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    • pp.235-243
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    • 1996
  • 콘크리트의 역학적거동은 다양한 종류의 균열의 발생과 전파에 의하여 영향을 받는다. 최근 고성능 콘크리트의 개발이 이루어지면서 계면파괴와 계면역에서의 균열양상에 대한 연구가 중요한 분야로 부각되고 있다. 탄성이며 균질한 재료에 적용되는 균열전파에 대한 규준은 계면역에서 균열이 진전하는 경우는 유효하지 않으며 이 경우에는 콘크리트에서 균열전파를 예측하기 위하여 구성재료들의 파괴인성과 그들 사이 계면의 파괴인성의상대적인 크기를 고려하여야 한다. 본 논문에서는 계면균열선단에서 계면파괴역학변수인 에너지해방률과 하중위상각을 수치해석방법을 이용하여 구하는 방법과 계면에서의 균열전파의 예측을 위한 에너지해방률에 기초를 둔 파괴규준을 제안하였다. 계면역에서의 균열양상을 조사하기 위하여 계면균열을 가진 이상복합모델에 대한 실험과 수치해석연구를 수행하였으며 대체적으로 실험결과와 규준을 이용하여 예측한 결과가 서로 일치하는 결과를 얻었다.