Dynamic Crack Propagation Behavior of the Mg-Li Alloys under High-Speed Impact Loading

Abstract:

The dynamic experiments for the Mg-Li alloys with single phase structure were carried out using the Hopkinson pressure bar. The dynamic crack propagation behavior and fracture mechanism of the alloys were investigated. The results show that the dynamic crack propagation is a deceleration process for the Mg-Li alloys under high loading rate. The fastest crack propagation velocity for Mg-3.3Li alloy is m/s 37 . 1253 , and 935.36m/s for Mg-14Li alloy. Observations of the fracture by SEM reveal that the dynamic fracture surface for Mg-3.3Li alloy mainly appears to be brittle fracture along grain boundaries. Whereas, the Mg-14Li alloy is ductile fracture mode under high loading rate. The main reason for these may be the transformation of hcp→bcc structure and the precipitation of the MgLi2Al and AlLi, as increase of Li in Mg-Li alloy.

• Periodical: Materials Science Forum (Volumes 488-489)
• Pages: 717-720
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.488-489.717
• Online since: July 2005
• Authors: Gui Ying Sha, Yong Bo Xu, En-Hou Han
• Keywords: Crack Propagation, Fracture Mechanic, Impact Loading, Mg-Li Alloy

References

[1] P. Metenier, G.G. Doncel and O.A. Ruano: Materials Sci. Eng., A125 (1990), p.195.

[2] F. R. Cao, J. Z. Cui and F. Lei: Mater. Eng., 9 (1996), p.3.

[3] D.M. Schwartz, J.B. Mitchell and J.E. Dorn: Acta Metall., 15 (1967), p.485.

[4] W.P. Hong, P.C. Hau and S. Lee: Materials Science Forum, Vol. 419-422 (2003), p.165.

[5] G.Y. Sha, R.T. Liu and F.C. Jiang: Explosion and Impact, 1 (2002), p.36.

[6] C. J. Ma, D. Zhang and J. N. Tan: Mater. Eng., 5 (2001), p.12.