English
Related papers

Related papers: Ab Initio Models of Dislocations

200 papers

Linear complexions are defect phases that form in the presence of dislocations and thus are promising for the direct control of plasticity. In this study, atomistic simulations are used to model the effect of linear complexions on…

Materials Science · Physics 2023-03-23 Divya Singh , Vladyslav Turlo , Daniel S. Gianola , Timothy J. Rupert

Two-dimensional simulations of the coarsening process of the isotropic/smectic-A phase transition are presented using a high-order Landau-de Gennes type free energy model. Defect annihilation laws for smectic disclinations, elementary…

Soft Condensed Matter · Physics 2008-06-30 Nasser Mohieddin Abukhdeir , Alejandro D Rey

Equations for dislocation evolution bridge the gap between dislocation properties and continuum descriptions of plastic behavior of crystalline materials. Computer simulations can help us verify these evolution equations and find their…

Materials Science · Physics 2020-11-11 Kamyar M. Davoudi , Joost J. Vlassak

Dislocations, line defects in crystalline materials, play an essential role in the mechanical[1,2], electrical[3], optical[4], thermal[5], and phase transition[6] properties of these materials. Dislocation motion, an important mechanism…

Materials Science · Physics 2023-07-04 Mingqiang Li , Yidi Shen , Kun Luo , Qi An , Peng Gao , Penghao Xiao , Yu Zou

The interaction between vacancies and edge dislocations in face centered cubic metals (Al, Au, Cu, Ni) is studied at different length scales. Using empirical potentials and static relaxation, atomic simulations give us a precise description…

Materials Science · Physics 2021-01-12 Emmanuel Clouet

Dislocations are the main carriers of the permanent deformation of crystals. For simulations of engineering applications, continuum models where material microstructures are represented by continuous density distributions of dislocations…

Materials Science · Physics 2018-03-02 Xiaohua Niu , Yichao Zhu , Shuyang Dai , Yang Xiang

The intersection between dislocations and a Ag(111) surface has been studied using an interplay of scanning tunneling microscopy (STM) and molecular dynamics (MD). Whereas the STM provides atomically resolved information about the surface…

This letter introduces ab initio study of the full activation-volume tensor of crystalline defects as a means to make contact with mechanical response experiments. We present a theoretical framework for prediction of the internal friction…

Materials Science · Physics 2015-06-24 H. Ustunel , D. Roundy , T. A. Arias

In this paper we have investigated, through computer simulations, dislocation nucleation and dislocation dynamics in a heterostructure system with the lattice-mismatch interface, i.e. a system with internal strain. In particular, we have…

Materials Science · Physics 2018-04-20 Marco Patriarca , Antti Kuronen , Kimmo Kaski

Plastic deformation In crystalline materials is controlled by the motion and interactions of dislocations [AND 17]. Discrete Dislocation Dynamics (DDD) simulations have now existed for about 25 years to investigate plastic flow at the…

Materials Science · Physics 2020-01-07 Sylvain Queyreau

Generally displacement fields in the vicinity of voids were determined by the equations of theory of elasticity. Such a description has its disadvantages as it does not take into account the discrete atomic structure of materials and it…

Materials Science · Physics 2017-04-18 A. V. Nazarov , I. V. Ershova , Y. S. Volodin

New aspects of a relation between lattice and dislocation structures are examined within a physically transparent theoretical scheme. Predicted features originating from the lattice discreteness include: (i) multiple core dislocation…

Materials Science · Physics 2007-05-23 Oleg N. Mryasov , Yu. N. Gornostyrev , A. J. Freeman

Over the past decades, discrete dislocation dynamics simulations have been shown to reliably predict the evolution of dislocation microstructures for micrometer-sized metallic samples. Such simulations provide insight into the governing…

A dislocation moving through a quasicrystal is leaving in its wake a fault denoted phason wall. For a two-dimensional model quasicrystal the disregistry energy of this phason wall is studied to determine possible Burgers vectors of the…

Materials Science · Physics 2008-02-03 R. Mikulla , P. Gumbsch , H. -R. Trebin

In this paper a geometric field theory of dislocation dynamics and finite plasticity in single crystals is formulated. Starting from the multiplicative decomposition of the deformation gradient into elastic and plastic parts, we use…

Materials Science · Physics 2023-08-02 Fabio Sozio , Arash Yavari

The kinetics of dislocations is studied with computer simulation at loadings of different intensity. It is established that the dislocations have a few different structural states. The dislocations "with the micropore" play important role…

Materials Science · Physics 2007-05-23 L. S. Metlov

In linearised continuum elasticity, the elastic strain due to a straight dislocation line decays as $O(r^{-1})$, where $r$ denotes the distance to the defect core. It is shown in Ehrlacher, Ortner, Shapeev (2016) that the core correction…

Analysis of PDEs · Mathematics 2017-10-24 Julian Braun , Maciej Buze , Christoph Ortner

The lifetime and performance of any engineering component, from nanoscale sensors to macroscopic structures, are strongly influenced by fracture processes. Fracture itself is a highly localized event; originating at the atomic scale by bond…

Materials Science · Physics 2022-10-04 Dominik Steinberger , Inas Issa , Rachel Strobl , Peter J. Imrich , Daniel Kiener , Stefan Sandfeld

Plasticity modelling has long been based on phenomenological models based on ad-hoc assuption of constitutive relations, which are then fitted to limited data. Other work is based on the consideration of physical mechanisms which seek to…

Materials Science · Physics 2022-06-06 Stefan Hiemer , Haidong Fan , Michael Zaiser

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…

Materials Science · Physics 2018-05-31 Marco Salvalaglio , Rainer Backofen , K. R. Elder , Axel Voigt