Skip to main content
Log in

Dynamic fracture toughness of high strength metals under impact loading: increase or decrease

  • Research Paper
  • Published:
Acta Mechanica Sinica Aims and scope Submit manuscript

Abstract

An elusive phenomenon is observed in previous investigations on dynamic fracture that the dynamic fracture toughness (DFT) of high strength metals always increases with the loading rate on the order of TPa·m1/2·s−1. For the purpose of verification, variation of DFT with the loading rate for two high strength steels commonly used in the aviation industry, 30CrMnSiA and 40Cr, is studied in this work. Results of the experiments are compared, which were conducted on the modified split Hopkinson pressure bar (SHPB) apparatus, with striker velocities ranging from 9.2 to 24.1 m/s and a constant value of 16.3 m/s for 30CrMnSiA and 40Cr, respectively. It is observed that for 30CrMn-SiA, the crack tip loading rate increases with the increase of the striker velocity, while the fracture initiation time and the DFT simultaneously decrease. However, in the tests of 40Cr, there is also an increasing tendency of DFT, similar to other reports. Through an in-depth investigation on the relationship between the dynamic stress intensity factor (DSIF) and the loading rate, it is concluded that the generally increasing tendency in previous studies could be false, which is induced from a limited striker velocity domain and the errors existing in the experimental and numerical processes. To disclose the real dependency of DFT on the loading rate, experiments need to be performed in a comparatively large striker velocity range.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Lee, Y., Prakash, V.: Dynamic brittle fracture of high strength structural steels under conditions of plane strain. Int. J. Solids Struct. 36, 3293–3337 (1999)

    Article  MATH  Google Scholar 

  2. Rosakis, A.J., Ravichandran, G.: Dynamic failure mechanics. Int. J. Solids Struct. 37, 331–348 (2000)

    Article  MATH  Google Scholar 

  3. Freund, L.B.: Dynamic Fracture Mechanics. Cambridge University Press, Cambridge, U.K., 1990

    Book  MATH  Google Scholar 

  4. Qiu, H., Enoki, M., Kawaguchi, Y., et al.: A model for the dynamic fracture toughness of ductile structural steel. Eng. Fract. Mech. 70, 589–598 (2003)

    Article  Google Scholar 

  5. Cui, Z.: Theories and Methods for Evaluation of Fracture Toughness. Shanghai Science and Technology Press, Shanghai, (1990) (in Chinese)

    Google Scholar 

  6. Klepaczko, J.R.: Load rate spectra for fracture initiation in metals. Theor. Appl. Fract. Mech. 1, 181–191 (1984)

    Article  Google Scholar 

  7. Ravi-Chandar, K., Knauss, W.G.: An experimental investigation into dynamic fracture–I. Crack initiation and crack arrest. Int. J. Fract. 25, 247–262 (1984)

    Article  Google Scholar 

  8. Kalthoff, J.F.: Fracture behaviour under high rates of loading. Eng. Fract. Mech. 23, 289–298 (1986)

    Article  Google Scholar 

  9. Zehnder, A.T., Rosakis, A.J.: Dynamic fracture initiation and propagation in 4340 steel under impact loading. Int. J. Fract. 43, 271–282 (1990)

    Article  Google Scholar 

  10. Li, C.J.: Effects of temperature and loading rate on fracture toughness of structural steels. Mater. Design 21, 27–30 (2000)

    Article  MATH  Google Scholar 

  11. Ruiz, C., Mines, R.A.W.: The Hopkinson pressure bar, an alternative to the instrumented pendulum for Charpy tests. Int. J. Fract. 29, 101–109 (1985)

    Article  Google Scholar 

  12. Rubio, L., Fernández-sáez, J., Navarro, C.: Determination of dynamic fracture-initiation toughness using three-point bending tests in a modified Hopkinson pressure bar. Exp. Mech. 43, 379–386 (2003)

    Article  Google Scholar 

  13. Yokoyama, T., Kishida, K.: A novel impact three-point bend test method for determining dynamic fracture-initiation toughness. Exp. Mech. 29(2), 188–194 (1989)

    Article  Google Scholar 

  14. Guo, W., Li, Y., Liu, Y.: Analytical and experimental determination of dynamic impact stress intensity factor for 40Cr steel. Theor. Appl. Fract. Mech. 26, 29–34 (1997)

    Article  Google Scholar 

  15. Jiang, F., Liu, R., Zhang, X., et al.: Evaluation of dynamic fracture toughness KId by Hopkinson pressure bar loaded instrumented Charpy impact test. Eng. Fract. Mech. 71, 279–287 (2004)

    Article  Google Scholar 

  16. Li, Y., Guo, W., Jia, D., et al.: Experimental measurement of dynamic fracture initiation toughness of 40Cr steel. Explosion and Shock Waves 16(1), 21–30 (1996) (in Chinese)

    Google Scholar 

  17. Liu, R., Zhang, X., Jiang, F., et al.: Study of the method for measuring dynamic fracture toughness by Hopkinson pressure bar technique. J. Harbin Eng. Univ. 21(6), 18–25 (2000) (in Chinese)

    MathSciNet  Google Scholar 

  18. Rubio-González C., Gallardo-González J.A., Mesmacque G., et al.: Dynamic fracture toughness of pre-fatigued materials. Int. J. Fatigue 30, 1056–1064 (2008)

    Article  Google Scholar 

  19. Xu, Z., Li Y., Li N., et al.: Effect of loading rate on mode I dynamic fracture toughness of high strength steels 40Cr and 30CrMnSiNi2A. Acta Metall. Sin. 42, 965–970 (2006) (in Chinese)

    Google Scholar 

  20. Xu, Z., Li, Y.: A novel method for evaluating plane stress dynamic fracture toughness of 0Cr18Ni10Ti stainless steel welded joints. Acta Metall. Sin. (Engl. Lett.) 21(4), 303–312 (2008)

    Article  Google Scholar 

  21. Li, Y., Liu, Y.: Theory and Test Research on Dynamic Fracture Toughness and Dynamic Crack Propagation. Northwest Polytechnical University Press, Xi’an, (1995) (in Chinese)

    Google Scholar 

  22. Xu, Z., Li, Y.: Study of loading rate effect on dynamic fracture toughness of high strength steel under impact loading. Strength, Fracture and Complexity 6, 17–23 (2010)

    Google Scholar 

  23. Zhao, Y.: The advances of studies on the dynamic initiation of cracks. Advances in Mechanics 26(3), 362–378 (1996) (in Chinese)

    MATH  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Ze-Jian Xu.

Additional information

The project was supported by the 111 Project (B07050) and the National Natural Science Foundation of China (10932008).

Rights and permissions

Reprints and permissions

About this article

Cite this article

Xu, ZJ., Li, YL. Dynamic fracture toughness of high strength metals under impact loading: increase or decrease. Acta Mech Sin 27, 559–566 (2011). https://doi.org/10.1007/s10409-011-0440-1

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10409-011-0440-1

Keywords

Navigation