Abstract
When ultrafine-grained (UFG) samples are deformed plastically, it is necessary to consider the role of grain boundaries even at the micrometer scale in sample size. We report here the occurrence of intensive grain boundary sliding (GBS) at room temperature in micro-pillars of a UFG aluminum alloy having an unusually high strain rate sensitivity. A consequence of this GBS is that the intermittent flow with detrimental strain avalanches characterizing micro-sized conventional crystals is not present in UFG materials, thereby illustrating a potential for effectively applying these UFG materials in micro-devices.
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Acknowledgments
This work was supported by the Hungarian ScientificResearch Fund (OTKA) under Grant Nos. K81360 and K67692 (NQC), by the Russian Foundation for Basic Research and Federal Agency for Science and Innovations (RZV) and by the National Science Foundation of the United States under Grant No. DMR-0855009 (TGL). The European Union and the European Social Fund provided financial support for this project under Grant Agreement No. TÁMOP 4.2.1./B-09/1/KMR-2010-0003.
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Chinh, N.Q., Győri, T., Valiev, R.Z. et al. Observations of unique plastic behavior in micro-pillars of an ultrafine-grained alloy. MRS Communications 2, 75–78 (2012). https://doi.org/10.1557/mrc.2012.11
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DOI: https://doi.org/10.1557/mrc.2012.11