Advertisement

Journal of Failure Analysis and Prevention

, Volume 13, Issue 1, pp 90–97 | Cite as

Optimizing the Prestrain Fatigue Performance of Transformation-Induced Plasticity-Aided Steel

  • Daniel J. Thomas
Technical Article---Peer-Reviewed
  • 176 Downloads

Abstract

The cut-edge properties of automotive structures formed during the manufacturing processes significantly influence fatigue and formability performance of high-strength steels. This factor is becoming increasingly important as advanced high-strength transformation-induced plasticity TRiP-aided DP600 steels under examination exhibit an increased sensitivity to fatigue cracks initiating from mechanical cut-edges. It was determined that under prestraining, the effects of plastic deformation of the microstructure can be used to optimize fatigue life. This was particularly the case where the prestraining significantly improved the fatigue lives of mechanical cut-edges up to a prestrain level of 5%. It is proposed that the effect of prestraining can be used to optimize the fatigue lives of even damaged mechanical cut-edges. These parameters can be used in the manufacture of structures with both optimum formability and fatigue lives.

Keywords

TRiP-aided DP AHSS Prestrain fatigue 

Abbreviations

AHSS

Advanced high-strength steel

HAZ

Heat-affected zone

HCF

High cycle fatigue

LCF

Low cycle fatigue

TRiP

Transformation-induced plasticity

List of Symbols

A

Elongation to failure

EN

Strain–life

LCF

Low cycle fatigue

R

Stress ratio (min stress/max stress)

SN

Stress–life

Notes

Acknowledgments

The present research was funded by a grant from the Engineering and Physical Sciences Research Council (EPSRC). The author wishes to gratefully acknowledge the support of Swansea University College of Engineering and the Engineering Centre for manufacturing and materials during the pursuit of this research.

References

  1. 1.
    Kishida, K.: High strength steel sheet for light weight vehicle. NIPPON Steel Tech. Rep. 81, 12–16 (2000)Google Scholar
  2. 2.
    Thomas, D.J., Whittaker, M.T., Bright, G.W., Gao, Y.: The influence of mechanical and CO2 laser cut-edge characteristics on the fatigue life performance of high strength automotive steels. J. Mater. Process. Technol. 211, 263–274 (2011)CrossRefGoogle Scholar
  3. 3.
    Meurling, F., Melander, A., Linder, J., Larsson, M., Trogen, H.: The influence of laser cutting on the fatigue properties of thin sheet steels. Swedish Institute for Metals Research Report IM-3691 (1998)Google Scholar
  4. 4.
    Keeler, S.: Cutting sheet metal reduces edge formability. The Science of Forming Magazine Article, March (1999)Google Scholar
  5. 5.
    Schaeffler, D.J.: Introduction to advanced high strength steels part I: grade overview. http://www.thefabricator.com/MetalsMaterials/MetalsMaterials_Article.cfm?ID=1139 (2005). Accessed 6 Dec 2012
  6. 6.
    Thomas, D.J.: Effect of mechanical cut-edges on the fatigue and formability performance of advanced high-strength steels. J. Fail. Anal. Prev. 12, 518–531 (2012)CrossRefGoogle Scholar
  7. 7.
    Yan, B.: Fatigue behaviour of advanced high strength steels for automotive applications. In: Great Designs in Steel Seminar. American Iron and Steel Institute, Washington, DC, pp. 1–22 (2003)Google Scholar
  8. 8.
    Maronne, E., Galtier, A., Labesse-Jied, F., Robert, J.L.: Influence of a cut edge on steel sheets fatigue properties. In: Proceedings of the 5th EIS International Conference Fatigue 2003 on Fatigue & Durability Assessment of Materials, Components and Structures, Cambridge, 7–9 Apr 2003, pp. 323–330 (2003)Google Scholar
  9. 9.
    Yanm, B., Xu, K.: In: 44th Mechanical Working and Steel Processing Conference Proceedings. Iron and Steel Society, AIME, Warrendale, PA, vol. 40, p. 493 (2002)Google Scholar
  10. 10.
    Song, S.M., Sugimoto, K.-I., Kandaka, S., Futamura, A., Kobayashi, M., Masuda, S.: Effects of prestraining on high-cycle fatigue strength of high-strength low alloy TRIP-aided steels. Mater. Sci. Res. Int. 9, 223–229 (2003)Google Scholar
  11. 11.
    Meurling, F., Melander, A., Linder, J., Larsson, M.: The influence of mechanical and laser cutting on the fatigue strengths of carbon and stainless sheet steels. Scand. J. Metall. 30, 309–319 (2001)CrossRefGoogle Scholar
  12. 12.
    Zackay, V.F., Parker, E.R., Fahr, D., Bush, R.: The enhancement of ductility in high strength steels. Trans. ASM 60, 252–259 (1967)Google Scholar
  13. 13.
    Matsumura, O., Sakuma, Y., Takechi, H.: TRIP and its kinetic aspects in austempered 0.4C–1.5Si–0.8Mn steel. Scr. Metall. 27, 1301–1306 (1987)CrossRefGoogle Scholar
  14. 14.
    Srivastava, A.K., Bhattacharjee, D., Jha, G., Gope, N., Singh, S.B.: Microstructural and mechanical characterization of C–Mn–Al–Si cold-rolled TRIPaided steel. Mater. Sci. Eng. A 446, 549–557 (2007)CrossRefGoogle Scholar
  15. 15.
    Takechi, H., Matsumura, O., Sakuma, Y.: Japan Kokai Tokyo Koho Japan Patent 62, vol. 188, p. 729 (1987)Google Scholar
  16. 16.
    Sugimoto, K.I., Kanda, A., Kikuchi, R., Hashimoto, S.I., Kashima, T., Ikeda, S.A.: Ductility and formability of newly developed high strength low alloy TRIP-aided sheet steels with annealed martensite matrix. ISIJ Int. 42, 910–915 (2002)CrossRefGoogle Scholar

Copyright information

© ASM International 2012

Authors and Affiliations

  1. 1.Materials Research Centre, College of EngineeringSwansea UniversitySwanseaUK

Personalised recommendations