• 제목/요약/키워드: Self-Piercing rivet

검색결과 27건 처리시간 0.026초

차체 셀프-피어싱 리벳 접합의 구조강성 및 피로수명 평가 (Assessment of Structural Stiffness and Fatigue Life in Self-Piercing Rivet(SPR) Joint of Car Body)

  • 김민건;이근찬;이병준
    • 대한기계학회논문집A
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    • 제28권8호
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    • pp.1174-1182
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    • 2004
  • Recently, Self Piercing Rivet(SPR) has been spotlighted in the automotive industry as a substitutive resort of spot welding and has also been watched by the designer as lightening a car body due to their superior assembly processes. Fatigue behavior of SPR joint needs to be investigated experimentally and numerically to predict its structural stiffness and fatigue life. Testing of lap-shear specimens with various material combinations is performed to obtain the joining strength and the fatigue life of SPR connections. The simulation of SPR lap-shear specimens is also conducted to obtain the structural stiffness of SPR connections under different material combinations. A Finite element model of the SPR lap-shear specimen is developed using a FEMFAT SPR pre-processor. The fatigue lift of SPR specimen is predicted using a FEMFAT 4.4e based on the liner finite element analysis.

유리섬유 강화 플라스틱과 알루미늄 합금 접합을 위한 유한요소해석 (Finite element analysis for joining glass fiber reinforced plastic and aluminium alloy sheets)

  • 조해용;김동범
    • Journal of Welding and Joining
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    • 제33권2호
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    • pp.78-84
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    • 2015
  • Self-piercing rivet(SPR) is mechanical joining methods and which can be joining dissimilar materials. Unlike conventional riveting, SPR also needs no pre-drilled holes. During plastically deformation, SPR pierces upper sheet and joins it to under sheet. SPR has been mainly applied to the joining the automobile body and some materials, such as glass fiber reinforced polymer and aluminum alloy, which represent the sheet-formed materials for lightweight automobile. Glass fiber reinforced plastic(GFRP) has been considered as a partial application of the automobile body which is lighter than steels and stronger than aluminium alloys. It is needed SPR to join Al alloy sheets and GFRP ones. In this paper, in order to design the rivet and anvil, which are suitable for GFRP, the joinability was examined through simulations of SPR joining between GFRP and Al alloy sheets. For this study, AutoCAD was used for the modeling and the simulated using commercial FEM code DEFORM-2D. The simulated results for SPR process joining between GFRP and Al alloys were confirmed by the same conditions as experimental trials.

알루미늄 합금과 고장력 강판 접합을 위한 헬리컬 SPR의 설계 (Design of Helical Self-Piercing Rivet for Joining Aluminum Alloy and High-Strength Steel Sheets)

  • 김원영;김동범;박진근;김도훈;김기호;이인환;조해용
    • 대한기계학회논문집A
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    • 제38권7호
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    • pp.735-742
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    • 2014
  • Self-piercing rivet(SPR)은 이종재료 접합을 위해 사용되는 결합용 기계요소로써, 대표적으로는 알루미늄 합금과 강판 등 용융점이 서로 다른 재료의 접합에 사용된다. SPR 접합은 일반 리벳접합과 달리 스스로 홀을 가공하며 삽입되기 때문에 사전의 홀 가공이 필요 없다.(1) 상부판재를 천공하고 하부판재와 함께 소성 변형되어 결합된다. 자동차의 차체 경량화를 위해서는 알루미늄 합금과 같은 경량소재가 사용되며, 부분적으로 스틸과 알루미늄 합금의 이종재료 접합이 요구된다. 그러나 알루미늄 합금과 강판은 용융점이 다르므로 기존의 차체 결합방법으로 이용되고 있는 저항 용접이 불가능하다. 이에 따라, 기계적 결합방법의 하나인 SPR 접합이 요구된다.(2) 따라서 본 연구에서는 강소성 유한요소해석 프로그램을 이용하여 리벳과 판재의 접합 성형성을 검토하고, 고장력 강판을 접합할 수 있는 새로운 형상의 SPR을 설계하였다. 또한 해석결과와 실험의 비교를 통하여 해석의 신뢰성을 검증하였다.

이종재료 Self-Piercing Rivets 접합부의 인장-전단 피로강도 (Tensile-Shear Fatigue Strength of Self-Piercing Rivets Joining Dissimilar Metal Sheets)

  • 강세형;김택영;오만진;김호경
    • 한국안전학회지
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    • 제30권4호
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    • pp.1-7
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    • 2015
  • Self-piercing riveting (SPR) process is gaining popularity due to its many advantages. The SPR does not require a pre-drilled hole and has capability to join a wide range of similar or dissimilar materials and combinations of materials. This study investigated the fatigue strength of self-piercing rivet joint with aluminum alloy (Al-5052) and steel (SPCC) sheets. Static and fatigue tests on tensile-shear specimens were conducted. From the static strength aspect, the optimal punching force for the specimen with upper SPCC (U.S) sheet and lower aluminum alloy(L.A) sheets was 34 kN. During static test the specimens fractured in pull-out fracture mode due to influence of plastic deformation of joining area. There was a relationship between applied load amplitude $P_{amp}$ and number of cycles N ; $P_{amp}=19588N_f^{-0.211}$ and $P_{amp}=4885N_f^{-0.083}$ for U.S-L.A and U.A-L.S specimens, respectively. U.A-L.S fatigue specimens failed due to fretting crack initiation around the rivet neck between upper and lower sheets.

Al/Fe 이종금속 접합부의 부식특성 (Corrosion Assessment of Al/Fe Dissimilar Metal Joint)

  • 강민정;김철희;김준기;김동철;김종훈
    • Journal of Welding and Joining
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    • 제32권4호
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    • pp.55-62
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    • 2014
  • The use of light-weight Al alloys in the automotive industry is increasing to meet requirements for fuel efficiency and emission reduction. Joining Al alloy to the conventional steel sheet is also very important issue with the increased use of Al alloy, and several joining processes have been introduced to enhance joining strength between dissimilar metals. This paper deals with a galvanic corrosion in the dissimilar metal joining. Salt spray tests up to 2000 hours were conducted on a self-piercing rivet, spot welded, adhesive bonded and weld-bonded joints, and cross-sections and tensile shear strength according the salt spray duration were analyzed at every 500-hour. Self-piercing rivet joint had relative low initial strength but the joint strength did not change regardless of the salt spray duration. The strength of other joints (spot welded, adhesive bonded and weld-bonded joints) decreased with the increase of salt spray duration and the corrosion behaviour of each joint was discussed.

이종재료의 결합방법에 따른 모자형 단면부재의 충돌실험 (Crushing Test of the Double Hat-shaped Members of Dissimilar Materials by Seining Methods)

  • 이명한;박영배;김헌영;오수익
    • 한국자동차공학회논문집
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    • 제13권4호
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    • pp.129-134
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    • 2005
  • There is a strong industrial demand for the development of light-weight vehicle to improve fuel efficiency and dynamic performance. The effective method of achieving the weight reduction is to use low-density materials such as aluminum and magnesium. In applying these materials to the vehicle, it is often required to join dissimilar materials such as aluminum and steel. However, conventional joining method, namely resistance spot welding cannot be used in joining dissimilar materials. Self·piercing rivet(SPR) and adhesive bonding is a good alternative to resistance spot welding. In this study, the impact test of double hat-shaped member made by resistance spot welding, SPR and adhesive bonding was performed. As a result, various parameters of crashworthiness were analyzed and evaluated. Also, the applicability of SPR and adhesive bonding as an alternative to resistance spot welding was suggested.

초고장력강과 알루미늄 합금의 판재 접합을 위한 헬리컬 SPR 설계 (Design of Helical SPR for Joining Advanced High Strength Steel and Aluminum Alloy Sheets)

  • 김동범;김관우;조해용
    • Journal of Welding and Joining
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    • 제33권6호
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    • pp.55-59
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    • 2015
  • Self-piercing riveting (SPR) is a sheet-joining method that can be used for materials that are difficult or unsuitable for weld, such as aluminum alloys and other steel sheet metals. The increased application of lightweight materials has initiated many investigations into new SPR conditions for riveting dissimilar materials. However, buckling of the semi-tubular rivet occurs during the riveting of AHSS. In this study, a helical SPR was designed for the riveting of AHSS and Al-alloy. In addition, the reinforced helical SPR which has straight parts was designed. The riveting of AHSS and Al-alloy was simulated. Simulated results were verified by comparison with experimental ones.