Stress-gradient plasticity.
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ABSTRACT:
SUBMITTER: Chakravarthy SS
PROVIDER: S-EPMC3179112 | biostudies-literature | 2011 Sep
REPOSITORIES: biostudies-literature
Publications
Stress-gradient plasticity.
Chakravarthy Srinath S SS Curtin W A WA
Proceedings of the National Academy of Sciences of the United States of America 20110912 38
A new model, stress-gradient plasticity, is presented that provides unique mechanistic insight into size-dependent phenomena in plasticity. This dislocation-based model predicts strengthening of materials when a gradient in stress acts over dislocation source-obstacle configurations. The model has a physical length scale, the spacing of dislocation obstacles, and is validated by several levels of discrete-dislocation simulations. When incorporated into a continuum viscoplastic model, predictions ...[more]
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