Kinematic properties of nanostructures based on bilayer nanocrystalline films

The kinematic properties of non-closed nanostructures formed from bilayer nanocrystalline Ni-Cu films were studied by a molecular dynamics method. The interatomic interaction was described in the framework of the embedded atom method. It is shown that when separated from the substrate with no external resisting forces, the initial film undergoes weakly damped oscillations whose amplitude depends on the stored elastic energy and eigenfrequencies on the geometric dimensions and crystallographic orientation of the initial film. The peculiarities of the atomic system behavior in bilayer nanocrystalline films on self-rolling were investigated. It is shown that during the process, vortex displacements of atomic groups occur near the film edges due to nonuniform stress distribution in the film. The vortex atomic displacements are dynamic defects and their generation is an accommodation mechanism by which the stress distribution reaches uniformity. The mechanisms disclosed in the study are of interest for designing component parts of various-purpose nanodevices.