Abstract
The microstructural features that govern the mechanical properties of wrought magnesium alloys include grain size, crystallographic texture, and twinning. Several processes based on shear deformation have been developed that promote grain refinement, weakening of the basal texture, as well as the shift of the peak intensity away from the center of the basal pole figure — features that promote room temperature ductility in Mg alloys. At ORNL, we are currently exploring the concept of introducing nano-twins within sub-micron grains as a possible mechanism for simultaneously improving strength and ductility by exploiting a potential dislocation glide along the twin-matrix interface — a mechanism that was originally proposed for face-centered cubic materials. Specifically, we have developed an integrated modeling and optimization framework in order to identify the combinations of grain size, texture and twin spacing that can maximize strength-ductility combinations. A micromechanical model that relates microstructure to material strength is coupled with a failure model that relates ductility to a critical shear strain and a critical hydrostatic stress. The micro-mechanical model is combined with an optimization tool based on genetic algorithm. A multi-objective optimization technique is used to explore the strength-ductility space in a systematic fashion and identify optimum combinations of the microstructural parameters that will simultaneously maximize the strength-ductility in the alloy.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
M.R. Barnett, et al. JOM, 61 (2009), pp. 19–24.
N. Stanford, and M. R. Barnett, Mater Sci and Eng. A., 496 (2008) pp. 399–408.
K. Lu, L. Lu, and S. Suresh, Science, 324 (2009) pp. 349–352.
Q. Yang, Q. and A. K. Ghosh, Acta materialia, 54 (2006) pp. 5159–5170.
K.L.Wu et al., Scripta Materialia, 64 (2011) pp. 213–216.
S.B. Gorti and B. Radhakrishnan, this Proceedings.
A. Jérusalem, M. Dao, S. Suresh and R. Radovitzky, Acta mater, 56 (2008) pp. 4647–4657.
Laboratory Directed Research and Development (LDRD) Program, ORNL 2012.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2013 TMS (The Minerals, Metals & Materials Society)
About this chapter
Cite this chapter
Radhakrishnan, B., Gorti, S.B., Simunovic, S. (2013). Multi-Objective Optimization of Microstructure in Wrought Magnesium Alloys. In: Li, M., Campbell, C., Thornton, K., Holm, E., Gumbsch, P. (eds) Proceedings of the 2nd World Congress on Integrated Computational Materials Engineering (ICME). Springer, Cham. https://doi.org/10.1007/978-3-319-48194-4_21
Download citation
DOI: https://doi.org/10.1007/978-3-319-48194-4_21
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-48585-0
Online ISBN: 978-3-319-48194-4
eBook Packages: Chemistry and Materials ScienceChemistry and Material Science (R0)