Deformation in metals was size dependent over length scales ranging from a few nm to 100μm. Two frameworks, dislocation dynamics and gradient plasticity, each having a length scale with different interpretation were discussed. It was suggested that various dislocation arrangements produce different physical behavior with different gradients and length scales.

Size Defects and Length Scales in Gradient Plasticity and Dislocation Dynamics. H.M.Zbib, E.C.Aifantis: Scripta Materialia, 2003, 48[2], 155-60

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