Nanoscale defect structures at crystal–glass interfaces

Abstract

A theoretical model of two-phase crystal-glass composite materials is suggested which is based on the disclination description of glassy structures. In the framework of the model, the crystal-glass composite is described as a solid that contains nanoscale configurations of disclination-dislocation loops in the glassy phase. Specific defects at the crystal-glass interface are defined and theoretically described which are misfit disclinations generated as extensions of parent wedge disclinations present in the glassy phase. In doing so, the defect ensemble in the crystal-glass composite is characterized by nanoscale inhomogeneities in both the defect density and stress in the vicinity of the crystal-glass interface. The formulae for the stress fields created by ensembles of the disclination-dislocation loops in crystal-glass composites are derived. With these formulae, the energy of the crystal-glass interface is estimated.

Rotating lattice single crystal architecture on the surface of glass

“…Alternatively, the glass itself can help nucleate the dislocation/disclination structure into the crystal, if we consider the disclination model of glass-crystal interface proposed by Ovidko et al 3839. Here a glass is viewed as a random distribution of disclinations, which destroy the long range order while retaining low-energy configurations related to the crystal structure4041.…”

“…The wedge disclinations of small strength (i.e. small rotation angle ω ) and line vector normal to scanning (crystal growing) direction of laser beam (see Figs 6 and 7) would extend from glassy phase into the crystal across the interface3839.…”

Elasticity Boundary-Value Problems for Straight Wedge Disclinations. A Review on Methods and Results

“…Elastic properties of disclinations were explored in calculating the difference of internal energy between amorphous and crystalline state [26], in the analysis of flow stress of metallic glasses [163], and in the analysis of the structure of crystal-glass interfaces [164].…”

Physical Mechanism of Nanocrystalline Composite Deformation Responsible for Fracture Plastic Nature at Cryogenic Temperatures

“…On the one hand, the choice of low-melting alloys allows for preserving the nanocrystalline/amorphous structure of films during the fusion of materials. On the other hand, a thin layer with unusual physical and mechanical properties is formed in the contact zone due to the reciprocal influence of nanocrystalline/amorphous and crystalline structures [ 24 , 25 , 26 , 27 ]. To analyze the features of the deformation and fracture process in such composites, it is necessary to conduct experimental studies in the widest possible temperature range.…”