Plastic deformation mediated by collective dislocation dynamics is investigated in the two-dimensional phase-field crystal model of sheared single crystals. We find that intermittent fluctuations in the dislocation population number accompany bursts in the plastic strain-rate fluctuations. Dislocation number fluctuations exhibit a power-law spectral density 1/f2 at high frequencies f. The proba...

We present a theory of the melting of elemental solids as a dislocation-mediated phase transition. We model dislocations near melt as non-interacting closed strings on a lattice. In this framework we derive simple expressions for the melting temperature and latent heat of fusion that depend on the dislocation density at melt. We use experimental data for more than half the elements in the Perio...

In this paper, the analytical solution of an electric and Volterra edge dislocation in a functionally graded piezoelectric (FGP) medium is obtained by means of complex Fourier transform. The system is subjected to in-plane mechanical and electrical loading. The material properties of the medium vary exponentially with coordinating parallel to the crack. In this study, the rate of the gradual ch...

The determination of dislocation distribution parameters is discussed for specimens where both strain broadening caused by dislocations and size broadening occur. If the strain broadening is well described by a model due to Wilkens, several methods are possible for the analysis of the broadening of diffraction lines. In sputter deposited nickel layers, three different methods for diffraction li...

The problem of several finite moving cracks in a functionally graded material is solved by dislocation technique under the condition of anti-plane deformation. By using the Fourier transform the stress fields are obtained for a functionally graded strip containing a screw dislocation. The stress components reveal the familiar Cauchy singularity at the location of dislocation. The solution is em...

The carrier profile for InAs films grown on GaP is modeled as a first-order approximation which assumes that 90° edge dislocation intersections and the threading dislocation intersections act as shallow donors. Due to dislocation annihilation during growth, the threading dislocation intersection density decreases as the inverse of the distance x from the InAs/GaP interface, D(x)5D0x0 /(x0 1x), ...

The size-dependence of the plastic response of single-crystal micropillars at submicron/micron length scales under compression was investigated using three-dimensional discrete dislocation dynamics (DDD) simulations. In the simulations, the initial dislocation configuration consists of randomly distributed Frank–Read-type dislocation sources. The simulation results are compared with a dislocati...

A FGM layer sandwiched between two isotropic layers weakened by several interface cracks under antiplane loading is studied. This paper examines the modelling of cracks by distribution of strain nuclei along crack lines. In this investigation, the Volterra-type screw dislocation employed between FGM and an elastic layer. To solve the dislocation problem, the complex Fourier transform is applied...

A FGM layer sandwiched between two isotropic layers weakened by several interface cracks under antiplane loading is studied. This paper examines the modelling of cracks by distribution of strain nuclei along crack lines. In this investigation, the Volterra-type screw dislocation employed between FGM and an elastic layer. To solve the dislocation problem, the complex Fourier transform is applied...