Abstract
There is compelling evidence for the critical role of twin boundaries (TBs) in imparting the extraordinary combination of strength and ductility to nanotwinned metals. Here, we investigate the thermal fluctuations of TBs in face-centered-cubic metals to elucidate the deformation mechanisms governing their kinetic properties using molecular dynamics simulations. Our results show that the TB motion is strongly coupled to shear deformation up to 0.95 homologous temperature. A rather unexpected observation is that coherent TBs do not exhibit any capillarityinduced fluctuations even at high temperatures, in sharp contrast to other high-angle grain boundaries.
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ACKNOWLEDGMENTS
The authors would like to acknowledge the support of the US National Science Foundation under grants DMR-1006876 and CMMI-1129041 and the Defense Advanced Research Projects Agency under grant N66001-10-1-4033. Yashashree Kulkarni would like to thank Professor Pradeep Sharma, University of Houston, for stimulating discussions. The simulations were performed on the supercomputing facility hosted by the Research Computing Center at University of Houston.
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Chen, D., Kulkarni, Y. Elucidating the kinetics of twin boundaries from thermal fluctuations. MRS Communications 3, 241–244 (2013). https://doi.org/10.1557/mrc.2013.37
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DOI: https://doi.org/10.1557/mrc.2013.37