Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-28T20:39:42.624Z Has data issue: false hasContentIssue false
  • English
  • Français

Modeling the strength and ductility of magnesium alloys containing nanotwins

Published online by Cambridge University Press:  10 April 2013

S.B. Gorti  and
B. Radhakrishnan
S.B. Gorti
Affiliation:
Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6114, U.S.A.
B. Radhakrishnan
Affiliation:
Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6114, U.S.A.
Get access

Abstract

Magnesium alloys have been receiving much attention recently as potential lightweight alternatives to steel for automotive and other applications, but the poor formability of these alloys at low temperatures has limited their widespread adoption for automotive applications. Recent work with face centered cubic (FCC) materials has shown that introduction of twins at the nanometer scale in ultra-fine grained FCC polycrystals can provide significant increase in strength with a simultaneous improvement in ductility. This objective of this work is to explore the feasibility of extending this concept to hexagonal close packed (HCP) materials, with particular focus on using this approach to increase both strength and ductility of magnesium alloys. A crystal plasticity based finite element (CPFE) model is used to study the effect of varying the crystallographic texture and the spacing between the nanoscale twins on the strength and ductility of HCP polycrystals. Deformation of the material is assumed to occur by crystallographic slip, and in addition to the basal and prismatic slip systems, slip is also assumed to occur on the {1 0 $\bar 1$ 1} planes that are associated with compression twins in these materials. The slip system strength of the pyramidal systems containing the nanotwins is assumed to be much lower than the strength of the other systems, which is assumed to scale with the spacing between the nanotwins. The CPFE model is used to compute the stress-strain response for different microstrucrutral parameters, and a criterion based on a critical slip system shear strain and a critical hydrostatic stress is used to compute the limiting strength and ductility, with the ultimate goal of identifying the texture and nanotwin spacing that can lead to the optimum values for these parameters.

Keywords

microstructuretexturepolycrystal
Type
Articles
Information
MRS Online Proceedings Library (OPL) , Volume 1513: Symposium GG – Mechanical Behavior of Metallic Nanostructured Materials , 2013 , mrsf12-1513-gg03-14
Copyright
Copyright © Materials Research Society 2013

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Lu, K., Lu, K. and Suresh, S., Science, 324, 349–352 (2009).10.1126/science.1159610CrossRefGoogle Scholar
Dao, M., Lu, L., Shen, Y. F. and Suresh, S., Acta Materialia, 54, 5421–5432 (2006).10.1016/j.actamat.2006.06.062CrossRefGoogle Scholar
Jerusalem, A., Dao, M., Suresh, S. and Radovitzky, R., Acta Materialia, 56, 4647–4657 (2008).10.1016/j.actamat.2008.05.033CrossRefGoogle Scholar
Sarma, G. B. and Radhakrishnan, B., Materials Science and Engineering A, 494, 92–102 (2008).10.1016/j.msea.2007.10.095CrossRefGoogle Scholar
Sarma, G. B., Radhakrishnan, B. and Zacharia, T., Computational Materials Science, 12, 105–123 (1998).10.1016/S0927-0256(98)00036-6CrossRefGoogle Scholar
Choi, S. H., Kim, D. H., Lee, H. W. and Shin, E. J., Materials Science and Engineering A, 527, 1151–1159 (2010).10.1016/j.msea.2009.09.055CrossRefGoogle Scholar
Wu, X. L., Youssef, K. M., Koch, C. C., Mathaudhu, S. N., Kecskes, L. J. and Zhu, Y. T., Scripta Materialia, 64, 213–216 (2011).10.1016/j.scriptamat.2010.10.024CrossRefGoogle Scholar
Lim, H., Lee, M. G., Kim, J. H., Adams, B. L. and Wagoner, R. H., International Journal of Plasticity, 27, 1328–1354 (2011).10.1016/j.ijplas.2011.03.001CrossRefGoogle Scholar