Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
권호 표지

Development of Technique to Improve the Formability of the Rear Floor in Series Stamping Process

연속 스탬핑 작업시 리어 플로어 성형성 향상기술 개발

  • 김동환 (전주국제대학교 자동차공학과) ;
  • 이정민 (부산대학교 대학원 정밀기계공학과) ;
  • 고영호 (부산대학교 대학원 정밀기계공학과) ;
  • 차해규 (진주산업대 기계공학과) ;
  • 김병민 (부산대학교 기계공학부)
  • Published : 2005.09.01
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, to improve the formability of the rear floor in series stamping process, the method for predicting the temperature of tools and steel sheet is proposed using FE analysis. To do this, tensile tests and straight pulling friction tests of three steel sheets are carried out at temperatures up to $300^{\circ}C$, and the effect of temperature on the tensile properties and the characteristics of friction are examined. The steel sheets have a higher n-value in the temperature range of about $50^{\circ}C$, and it is related to the maximum uniform elongation. Also, the blue shortness occurs in the temperature range of about $150^{\circ}C$. When the temperature is higher than $200^{\circ}C$, the friction coefficient increase with increasing temperature. From the FE-simulation, the effects of the punch temperature considering heat expansion in the number of stamping are examined and discussed. The technique developed in this study fur estimating tool temperature can be used to develop more feasible ways to improve continuous productivity in series stamping process.

Keywords

References

  1. Leighton, D. E. and Lee, D., 'The Effect of Tooling Temperature on the Formability of Sheet Steel,' Journal of MPT, Vol. 45, pp. 577 - 582, 1994
  2. Yoshida, T., Shidoda, T. and Sano, A., 'The Effect of Increase of Tool Temperature on Sheet Steel Forming,' Mold Technology, Vol. 11, No.8, pp. 28 - 29, 1996
  3. Song, K. H., Lee, J. D. and Seo, D. G., 'Friction Characteristic of Sheets for the Die Temperature and the Treating Conditions,' Transactions of Materials Processing, Vol. 8, No.3, pp. 245 - 251, 1999
  4. Lee, J. D., Choi, C. S., Choi, Y. C., Kim, H. Y. and Seo, D. G., 'A Study on the Warm Deep Drawing Ability of Sheets on Cr-Coating Die,' Transactions of Materials Processing, Vol. 9, No.2, pp. 186 - 192, 1999
  5. Choi, C. S., Choi, Y. C., Oh, Y. K., Lee, J. W. and Lee, H. S., 'Effect of Cold Forming Method on Drawability in Trunk Floor Panel,' Transactions of Materials Processing, Vol. 10, No.2, pp. 123 - 129, 2001
  6. Thomas, W., Oenoki, T. and Altan, T., 'Process Simulation in Stamping - Recent Applications for Product and Process Design,' Journal of MPT, Vol. 98, pp. 232 - 243, 2000 https://doi.org/10.1016/S0924-0136(99)00204-6
  7. Takuda, H., Mori, K., Masuda, I., Abe, Y. and Matsuo, M., 'Finite Element Simulation of Warm Deep Drawing of Aluminium Alloy Sheet When Accounting for Heat Conduction,' Journal of MPT, Vol. 120, pp. 412 - 418, 2002 https://doi.org/10.1016/S0924-0136(01)01180-3
  8. Ko, Y. H., Kim, B. M. and Kim, D. H., 'Prediction of Temperature Increase during Continuous Stamping Process by FE-simulation,' Proceedings of the KSPE Autumn Annual Meeting, pp. 974 - 977, 2003
  9. Kim, D. H., Lee, J. M., Ko, Y. H., Cha, H. G. and Kim, B. M., 'Development of Technique to Improve the Formability of the Rear Floor in Series Stamping Process,' Proceedings of the KSPE Autumn Annual Meeting, pp. 25 - 28, 2004
  10. Kim, D. H., Kim, B. M., Lee, Y. and Min, B. H., 'Friction Characteristics for Surface Finish and the Stoning Direction of Stoning Dies,' Proc. Instn. Mech. Engrs. Part B: J. Engineering Manufacture, Vol. 216, pp. 531 - 542, 2002
  11. Ohwue, T., Takechi, H. and Furuno, Y., 'Deep Drawability of Square Shells in Warm Working Condition,' Journal of JSTP, Vol. 28, No. 318, pp. 706 - 711, 1987
  12. Ohwue, T., Takechi, H. and Furuno, Y., 'Temperature Dependence of Tensile Properties Drawability of Steel Sheets in Warm Working Condition,' Journal of JSTP, Vol. 28, No. 314, pp. 225 - 231, 1987
  13. Basic Formability, Forming Technology INC., 1075 North Service Road West, Unit 6, Oakville, 1996
  14. Ike, H., 'Tribology of Galvanized Steel Sheet,' Press & Mold Technology, Vol. 11, pp. 100 - 104, 1992
  15. Kim, D. H. and Kim, B. M., 'Estimation of Die Service Life for Die Cooling Method in Hot Forging,' Transaction of Materials Processing, Vol. 12, No.4, pp. 408- 403, 2003 https://doi.org/10.5228/KSPP.2003.12.4.408
  16. www.matweb.com