Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
권호 표지

Fatigue Life Evaluation of Spot Weldments of SPC Sheet Including Strain Rate Effect

변형률속도효과를 고려한 일반냉연강판 점용접부의 피로수명평가

  • Song, Joon-Hyuk (Jeonju Machinery Research Center) ;
  • Nah, Seok-Chan (Division of Mechanical & Aerospace System Engineering, Chonbuk National University) ;
  • Yu, Hyo-Sun (Division of Mechanical & Aerospace System Engineering, Chonbuk National University) ;
  • Kang, Hee-Yong (Division of Mechanical & Aerospace System Engineering, Chonbuk National University) ;
  • Yang, Sung-Mo (Division of Mechanical & Aerospace System Engineering, Chonbuk National University)
  • 송준혁 ((재)전주기계산업리서치센터) ;
  • 나석찬 (전북대학교 기계항공시스템공학부) ;
  • 유효선 (전북대학교 기계항공시스템공학부) ;
  • 강희용 (전북대학교 기계항공시스템공학부) ;
  • 양성모 (전북대학교 기계항공시스템공학부)
  • Published : 2006.01.01
Download PDF
⟨ Previous Next ⟩

Abstract

A methodology is described for predicting the fatigue life of the resistance spot weldment including strain rate effect. Because it is difficult to perform a physical failure test with high strain rate, an analytical method is necessary to get the mechanical properties of various strain rate, To this end, quasi-static tensile-shear tests at several strain rate were performed on spot weldments of SPC. These test provided the empirical data with the strain rate. With these results, we formulated the function of fatigue life prediction using the lethargy coefficient which is the global material property from tensile test. And, we predicted the fatigue life of spot weldment at dynamic strain rate. To confirm this method for fatigue life prediction, analytical results were compared with the experimental fatigue data.

Keywords

References

  1. H. S. Yu, 'A Study on Ultrasonic Test for Evaluation of Spot Weldability in Automotive Materials,' KSME International Journal, Vol. 13, No.12, pp.775-782, 1999 https://doi.org/10.1007/BF03184559
  2. D. H. Bae, I. S. Sohn, W. S. Jung and H. K. Lee, 'Fracture Mechanical Fatigue Strength Evaluation of IB- Type Spot Welded Lap Joint under Tension-Shear Load,' KSME International Journal, Vol.6, No.5, pp.20-27, 1998
  3. S. H. Song, Y. J. Yang and J. W. Jeon, 'A Fatigue Behavior for Spot Welded Steel Plate Carbon C by the Variation of the Interval Between Two Spots,' Proceedings of KSME A, Vol.24, No.11, pp.2845-2852, 2000
  4. H. S. Yu, S. I. Lee, I. H. Kwon and B. G. An, 'Fatigue Life Evaluation of Spot Weldment Using DCPDM,' Journal of KWS, Vol.19, No.1, pp.58-64, 2001
  5. H. Kitagawa, T. Satoh and M. Fujimoto, 'Fatigue Strength of Single Spot-Welded Joints of Rephosphorized High-Strength and Low-Carbon Steel Sheets,' SAE 850371, pp.114-126, 1985
  6. M. Mizui, T. Sekine, A. Tsujimura, T. Takishima and Y. Shimazaki, 'An Evaluation of Fatigue Strength for Various Kinds of Spot-Welded Test Specimen,' SAE 880375, pp.382-391, 1988
  7. J. H. Song, H. G. Noh, H. S. Yu, H. Y. Kang and S. M. Yang, 'Estimation of Fatigue Life by Lethargy Coefficient using Molecular Dynamic Simulation,' Int. J. Automotive Technology, Vol.5, No.3, pp.215-219, 2004
  8. J. H. Song, H. G. Noh, H. Y. Kang and S. M. Yang, 'Estimation of Fatigue Strength with Practical Dynamic Force by Inverse Problem and Lethargy Coefficient,' Transactions of KSAE, Vol.12, No.1, pp.106-113, 2004
  9. D. A. Chatfield and R. R. Rote, 'Strain Rate Effect on the Properties of High Strength Low Allow Steels,' SAE 740077, 1977
  10. A. S. Korhonen and H. J. Kleemola, 'Effects of Strain Rate and Deformation Heating in Tensile Testing,' Metall. Trans. A, Vol.9A, pp.979-986, 1978