相关论文: Volume Contraction at a Grain Boundary in Vanadium
The effects of micro-alloying element, vanadium, on a bcc Fe \Sigma 3(111)[1-10] symmetric tilt grain boundary strength are studied using density functional theory calculations. The lowest energy configuration of the grain boundary…
Grain boundaries have extensive influence on the performance of crystal materials. However, the atomic-scale structure and its relation with local and crystallographic symmetries remain elusive in low-symmetry crystals. Herein, we find that…
We address a three-dimensional, coarse-grained description of dislocation networks at grain boundaries between rotated crystals. The so-called amplitude expansion of the phase-field crystal model is exploited with the aid of finite element…
According to classical grain growth laws, grain growth is driven by the minimization of surface energy and will continue until a single grain prevails. These laws do not take into account the lattice anisotropy and the details of the…
While computational methods for the study of point defects in materials have received significant attention, methods for the investigation of grain boundaries require further development. In this study, we applied a genetic algorithm to…
We present a theoretical study of the interaction of vacancies with a tilt grain boundary in aluminum based on the density functional theory. The grain boundary volume expansion and vacancy induced contraction are calculated and compared…
The macroscopic behavior of polycrystalline materials is influenced by the local variation of properties caused by the presence of impurities and defects. The effect of these impurities at the atomic scale can either embrittle or strengthen…
To investigate the barrier effect of grain boundaries on the propagation of avalanche-like plasticity at the atomic-scale, we perform three-dimensional molecular dynamics simulations by using simplified polycrystal models including…
We present a systematic trend study of the symmetric tilt grain boundaries about the <110> axis in molybdenum. Our results show that multiple structural phases, some incorporating vacancies, compete for the boundary ground state. We find…
An effect of the volume change upon proper ferroelastic (martensitic) phase transitions in cubic crystals is considered. Corresponding terms in the Ginzburg-Landau expansion of the Gibbs free energy are analyzed for the first- as well as…
The material properties of polycrystals are strongly affected by the evolution and coarsening of their internal grain structures. Yet, studying this process is challenging due to the complex interactions within grain boundary networks.…
We model two-dimensional systems of granular aggregates confined between two planes and demonstrate that at a critical grain volume fraction an abrupt rigidity transition occurs. This transition is observed both in static and shear tests.…
The boundary of a manifold can alter the phase of a theory in the bulk. We explore the possibility of a boundary-induced phase transition for the chiral symmetry of QCD. In particular, we investigate the consequences of imposing homogeneous…
The grain boundary-mediated mechanisms that control plastic deformation of nanocrystalline metals should cause evolution of the grain boundary network, since they directly alter misorientation relationships between crystals. Unfortunately,…
We explore the statistical properties of grain boundaries in the vortex polycrystalline phase of type II superconductors. Treating grain boundaries as arrays of dislocations interacting through linear elasticity, we show that…
Nanocrystalline metals contain a large fraction of high-energy grain boundaries, which may be considered as glassy phases. Consequently, with decreasing grain size, a crossover in the deformation behaviour of nanocrystals to that of…
Interactions between grain boundaries and domain walls were extensively studied in ferroelectric films and bicrystals. This knowledge, however, has not been transferred to polycrystalline ceramics, in which the grain size represents a…
Understanding and controlling the properties and dynamics of topological defects is a lasting challenge in the study of two-dimensional materials, and is crucial to achieve high-quality films required for technological applications. Here…
Grain boundaries in epitaxial graphene on the SiC(000$\bar{1}$) substrate are studied using scanning tunneling microscopy and spectroscopy. All investigated small-angle grain boundaries show pronounced out-of-plane buckling induced by the…
Grain rotation and grain boundary (GB) sliding are two important mechanisms for grain coarsening and plastic deformation in nanocrystalline materials. They are in general coupled with GB migration and the resulting dynamics, driven by…