On plastic strain recovery in freestanding nanocrystalline metal thin films
نویسندگان
چکیده
In a recent article [J. Rajagopalan, J.H. Han, M.T.A. Saif, Science 315 (2007) 1831–1834], we have reported substantial (50–100%) plastic strain recovery in freestanding nanocrystalline metal films (grain size 50–65 nm) after unloading. The strain recovery was time dependent and thermally activated. Here we model the time evolution of this strain recovery in terms of a thermally activated dislocation propagation mechanism. The model predicts an activation volume of 42b for the strain recovery process in aluminum. 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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