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A Study of Fatigue Life Prediction for Automotive Spot Weldment Using Local Strain Approach

국부변형률근사법을 이용한 차체 점용접부의 피로수명 예측에 관한 연구

  • Lee, Song-In (Automotive New Technology Research Center, Dept.of Mechanical Engineering, Chonbuk National University) ;
  • Gwon, Il-Hyeon (Automotive New Technology Research Center, Dept.of Mechanical Engineering, Chonbuk National University) ;
  • Lee, Beom-Jun (Dept.of Mechanical Engineering, Chonbuk National University) ;
  • Yu, Hyo-Seon
  • 이송인 (전북대학교 기계공학부, 자동차신기술연구소) ;
  • 권일현 (전북대학교 기계공학부, 자동차신기술연구소) ;
  • 이범준 (전북대학교 대학원 기계공학부) ;
  • 유효선
  • Published : 2001.02.01

Abstract

The fatigue crack initiation life is studied on automotive tensile-shear spot weldment made from cold rolled carbon steel(SPC) sheet by using DCPDM and local strain approach. It can be found that the fatigue crack initiation behavior in spot weldment can be definitely detected by DCPDM system. To predict the fatigue life of spot weldment, the local stresses and strains at the potential critical region are estimated by approximate method based on Neubers rule and elastic-plastic FEM analysis. A satisfactory correlation between the predicted life obtained from Local strain approach based on Neubers rule and experimental life can be found in spot weldment within a factor of 2.

Keywords

Spot Welding;Fatigue Crack Initiation Life;Local Strain Approach;DC Potential Drop Method

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