Plasticity at the micron scale

Authors
Citation
Jw. Hutchinson, Plasticity at the micron scale, INT J SOL S, 37(1-2), 2000, pp. 225-238
Citations number
32
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Mechanical Engineering
Journal title
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
ISSN journal
0020-7683 → ACNP
Volume
37
Issue
1-2
Year of publication
2000
Pages
225 - 238
Database
ISI
SICI code
0020-7683(200001)37:1-2<225:PATMS>2.0.ZU;2-6
Abstract
Over a scale which extends from about a fraction of a micron to tens of mic rons, metals display a strong size-dependence when deformed non uniformly i nto the plastic range: smaller is stronger. This effect has important impli cations for an increasing number of applications in electronics, structural materials and MEMS. Plastic behavior at this scale cannot be characterized by conventional plasticity theories because they incorporate no material l ength scale and predict no size effect. While micron sized solid objects ar e too small to be characterized by conventional theory, they are usually to o large to be amenable to analysis using approaches presently available bas ed on discrete dislocation mechanics. The relatively large number, of dislo cations governing plastic deformation at the micron scale motivate the deve lopment of a continuum theory of plasticity incorporating size-dependence. Strain gradient theories of plasticity have been developed for this purpose . The motivation and potential for such theories will be discussed. Importa nt open issues surrounding the foundations of strain gradient plasticity wi ll also be addressed and a few critical experiments identified. (C) 1999 El sevier Science Ltd. All rights reserved.