Evaluation of the Finite Element Modeling of Spot-Welded Region for Crash Analysis

충돌해석에서의 점용접부 모델링에 따른 하중특성 평가

  • Song, Jung-Han (Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology) ;
  • Huh, Hoon (Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology) ;
  • Kim, Hong-Gee (POSCO Technical Research Laboratories) ;
  • Kim, Sung-Ho (POSCO Technical Research Laboratories)
  • 송정한 (한국과학기술원 기계공학과) ;
  • 허훈 (한국과학기술원 기계공학과) ;
  • 김홍기 (포스코 기술연구소) ;
  • 박성호 (포스코 기술연구소)
  • Published : 2006.03.01

Abstract

The resistance spot-welded region in most current finite element crash models is characterized as a rigid beam at the location of the welded spot. The region is modeled to fail with a failure criterion which is a function of the axial and shear load at the rigid beam. The role of this rigid beam is simply to transfer the load across the welded components. The calculation of the load acting on the rigid beam is important to evaluate the failure of the spot-weld. In this paper, numerical simulation is carried out to evaluate the calculation of the load at the rigid beam. The load calculated from the precise finite element model of the spot-welded region considering the residual stress due to the thermal history during the spot welding procedure is regarded as the reference value and the value of the load is compared with the one obtained from the spot-welded model using the rigid beam with respect to the element size, the element shape and the number of imposed constraints. Analysis results demonstrate that the load acting on the spot-welded element is correctly calculated by the change of the element shape around the welded region and the location of welded constrains. The results provide a guideline for an accurate finite element modeling of the spot-welded region in the crash analysis of vehicles.

Keywords

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