Analysis of Hydroforming Process for an Automobile Lower Arm by Using Explicit and Implicit FEM

외연적과 내연적 유한요소법에 의한 자동차 로어암의 하이드로포밍 공정해석

  • Kim, Jeong (Dept.of Aerospace Engineeing, Graduate School of Busan National University) ;
  • Choi, Han-Ho (Dept.of Mechanical Engineering, Pukyong National University) ;
  • Kang, Beom-Soo (Dept.of Aerospace Engineeing, Busan National University)
  • 김정 (부산대학교 항공우주공학과 대학원) ;
  • 최한호 (부경대학교 기계공학부) ;
  • 강범수 (부산대학교 항공우주공학과)
  • Published : 2002.09.01

Abstract

Recently tube hydroforming has been widely applied to the automotive industries due to its several advantages over conventional methods. In this paper, attention is paid to comparison of an implicit and an explicit finite element method widely used for numerical simulation of a hydroforming process. For an explicit FEM, a huge amount of computational time is required because of the very small time increment to solve a quasi-static problem. Hence, when an explicit FEM is used fDr a hydroforming process, it is general to convert the real problem to a virtual problem with a different processing time and mass density by appropriate scaling factor. However it is difficult to figure out how large the scaling should be adopted enough to ignore the dynamic effects and maintain the desired accuracy. In this paper, the comparison of the results obtained from both methods focus on the accuracy of the predicted geometrical shape and the stress with various scaling factors which are applied to analyze hydroforming process of an automobile lower arm.

Keywords

References

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