We present an efficient high order method for dislocation dynamics simulation of vacancy-assisted dislocation climb in two dimensions. The method is based on a second kind integral equation (SKIE) formulation that represents the vacancy concentration via the sum of double layer potentials and point sources located at each dislocation center, where the climb velocity of each dislocation (or the ...

Plasticity is often controlled by dislocation motion, which was first measured for low pressure, low strain rate conditions decades ago. However, many applications require knowledge of dislocation motion at high stress conditions where the data are sparse, and come from indirect measurements dominated by the effect of dislocation density rather than velocity. Here we make predictions based on a...

An exactly solvable phase-field theory of dislocation dynamics, strain hardening and hysteresis in ductile single crystals is developed. The theory accounts for: an arbitrary number and arrangement of dislocation lines over a slip plane; the long-range elastic interactions between dislocation lines; the core structure of the dislocations resulting from a piecewise quadratic Peierls potential; t...

High-quality Ge films were grown on Si substrates by solid-source molecular beam epitaxy using SiGe graded layer and Sb surfactant-mediation technique. Transmission electron microscopy measurements show that samples grown using this method have a lower threading dislocation density than those grown by other typical methods, such as grading at high temperature ~700 °C! only, grading at intermedi...

A mesoscale model is developed by integrating the rate theory and phase-field models and is used to study the fission-induced recrystallization in U-7Mo alloy. The rate theory model is used to predict the dislocation density and the critical size and density of the recrystallized nuclei due to irradiation. The predicted fission rate and temperature dependences of the dislocation density are in ...

Dislocation-tuned functional properties such as electrical conductivity, thermal and ferroelectric in oxides are attracting increasing research interest. A prerequisite for harvesting these requires successful introduction control of dislocation density arrangement without forming cracks, which is a great challenge due to their brittle nature. Here, we report simple method mechanically tailor t...

The giant plasticity of [Formula: see text]He crystals has been explained as a consequence of the large mobility of their dislocations. Thus, the mechanical properties of dislocation free crystals should be quite different from those of usual ones. In 1996-1998, Ruutu et al. published crystal growth studies showing that, in their helium 4 crystals, the density of screw dislocations along the c-...

The defect structure onattice-mismatched I-pm InxGal_xAs X 10-3) epilayers on GaAs was studied with scanning cathodoluminescence (CL), transmission electron microscopy (TEM), high-voltage electron microscopy, and scanning electron microscopy. CL shows that nonradiative recombination lines exist in the GaAs buffer layer as far as 4000 A from the interface. The density of these defects is indepen...

We analyse a continuous magnon spectrum which is excited in FMR in a ferromagnetic sample with dislocations. Calculations are presented for the moments of the uniform mode. Numerical comparisons of the moment method with literature data and the Born approximation are given for the broadening of the resonance line. In monocrystalline ferromagnets, the dislocations have the remarkable effect on r...