Size-dependent grain-growth kinetics observed in nanocrystalline Fe.
Measurements of grain growth in nanocrystalline Fe reveal a linear dependence of the grain size on annealing time, contradicting studies in coarser-grained materials, which find a parabolic (or power-law) dependence. When the grain size exceeds approximately 150 nm, a smooth transition from linear to nonlinear growth kinetics occurs, suggesting that the rate-controlling mechanism for grain growth depends on the grain size. The linear-stage growth rate agrees quantitatively with a model in which boundary migration is controlled by the redistribution of excess volume localized in the boundary cores.
Krill
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FR 7.3 Technische Phsik, Universität des Saarland, Saarbrücken, Germany. krill@rz.uni-sb.de
Helfen
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L
Michels
D
D
Natter
H
H
Fitch
A
A
Masson
O
O
Birringer
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R