title: Stability map for nanocrystalline and amorphous materials.
abstract: We present a stability map which predicts the domains of shear instability due to grain rotation in nanocrystalline materials. The onset of this mode of instability is influenced by grain-size-dependent mechanisms and the length-scale of intergranular interaction. The map shows the grain size regimes that are inherently susceptible to this mode for a range of materials. In the amorphous limit, the model predicts embryonic nuclei sizes of about 10-50 nm, which agrees well with the shear band thicknesses for many metallic glasses.
authors.affiliation: Department of Mechanical Engineering, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA.
authors.forename: Shailendra P
authors.initials: SP
authors.lastname: Joshi
authors.forename: K T
authors.initials: KT
authors.lastname: Ramesh