In X-ray interference fringes accompanied by mirage diffraction, variations have been observed in the spacing and position of the fringes from a plane-parallel Si single crystal fixed at one end as a function of distance from the incident plane of the X-rays to the free crystal end. The variations can be explained by distortion of the sample crystal due to gravity. From the variations and posit...

Abstract We propose a phase-field theory for enriched continua. To generalize classical models, we derive the gradient based on balances of microforces, microtorques, and mass. focus materials where second gradients phase field describe long-range interactions. By considering nontrivial interaction inside body, described by boundary-edge microtraction, characterize existence hypermicrotraction ...

For very shallow indentations in W, Al, Au, and Fe-3wt%Si single crystals, hardness decreased with increasing depth irrespective of increasing or decreasing strain gradients. As such, strain gradient theory appears insufficient to explain the indentation size effect (ISE) at depths less than several hundred nanometers. Present research links the ISE to a ratio between the energy of newly create...

The phonon dispersion relations calculated by atomic model: shell model and ab initio, and by microcontinuum theory are introduced in this paper. It is found that both atomic models and microcontinuum theory can describe the common feature of phonon dispersion relation for the crystal having more than one atom per primitive cell and can give a good fit to the experimentally measured data. The o...