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Related papers: Dynamics and Patterning of Screw Dislocations in T…

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Collective motion of dislocations is governed by the obstacles they encounter. In pure crystals, dislocations form complex structures as they become jammed by their anisotropic shear stress fields. On the other hand, introducing disorder to…

Materials Science · Physics 2020-10-13 Henri Salmenjoki , Lasse Laurson , Mikko J. Alava

We have studied the ordering kinetics of a two-dimensional anisotropic Swift-Hohenberg (SH) model numerically. The defect structure for this model is simpler than for the isotropic SH model. One finds only dislocations in the aligned…

Soft Condensed Matter · Physics 2009-11-11 Hai Qian , Gene F. Mazenko

We show that driven dislocation assemblies exhibit a set of dynamical phases remarkably similar to those of driven systems with quenched disorder such as vortices in superconductors, magnetic domain walls, and charge density wave materials.…

Materials Science · Physics 2017-12-06 C. Zhou , C. Reichhardt , C. J. Olson Reichhardt , I. J. Beyerlein

We study the excitation of harmonic waves in thin elastic samples by a single dislocation in arbitrary motion. We consider both screw and edge dislocations that move perpendicularly to the surfaces of the layer. In Fourier space the…

Materials Science · Physics 2007-05-23 Rodrigo Arias , Fernando Lund

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…

Dislocation pinning plays a vital role in the plastic behaviour of a crystalline solid. Here we report the first observation of the damped oscillations of a mobile dislocation after it gets pinned at an obstacle in the presence of a…

Materials Science · Physics 2010-12-24 M. Bhattacharya , A. Dutta , P. Mukherjee , N. Gayathri , P. Barat

Metallic materials under high stress often exhibit deformation localization, manifesting as slip banding. Over seven decades ago, Frank and Read introduced the well-known model of dislocation multiplication at a source, explaining slip band…

The goal of this paper is the analytical validation of a model of Cermelli and Gurtin for an evolution law for systems of screw dislocations under the assumption of antiplane shear. The motion of the dislocations is restricted to a discrete…

Dynamical Systems · Mathematics 2014-10-24 Timothy Blass , Irene Fonseca , Giovanni Leoni , Marco Morandotti

The plasticity transition at the yield strength of a crystal typically signifies the tendency of dislocation defects towards relatively unrestricted motion. For an isolated dislocation the motion is in the slip plane with velocity…

Materials Science · Physics 2020-01-15 Péter Dusán Ispánovity , Stefanos Papanikolaou , István Groma

In this paper, we present a dislocation-density-based three-dimensional continuum model, where the dislocation substructures are represented by pairs of dislocation density potential functions (DDPFs), denoted by $\phi$ and $\psi$. The slip…

Materials Science · Physics 2015-09-23 Yichao Zhu , Yang Xiang

By means of linear theory of elastoplasticity, solutions are given for screw and edge dislocations situated in an isotropic solid. The force stresses, strain fields, displacements, distortions, dislocation densities and moment stresses are…

Materials Science · Physics 2007-05-23 Markus Lazar

Plastic deformation of metals involves the complex evolution of dislocations forming strongly connected dislocation networks. These dislocation networks are based on dislocation reactions, which can form junctions during the interactions of…

Materials Science · Physics 2022-08-22 Balduin Katzer , Kolja Zoller , Daniel Weygand , Katrin Schulz

When metals are plastically deformed, the total density of dislocations increases with strain as the microstructure is continuously refined, leading to the strain hardening behavior. Here we report the fundamental role played by the…

Materials Science · Physics 2018-08-29 Ryan B. Sills , Nicolas Bertin , Amin Aghaei , Wei Cai

The thermodynamic dislocation theory presented in preceding papers is used here to describe shear-banding instabilities. Central ingredients of the theory are a thermodynamically defined effective configurational temperature, and a formula…

Materials Science · Physics 2016-12-02 J. S. Langer

The statistical-thermodynamic dislocation theory developed in previous papers is used here in an analysis of high-temperature deformation of aluminum and steel. Using physics-based parameters that we expect theoretically to be independent…

Materials Science · Physics 2017-07-19 K. C. Le , T. M. Tran , J. S. Langer

We investigate the deformation of a longitudinally stretched rectangular sheet which is clamped at two opposite boundaries and free otherwise with experiments, numerical analysis and asymptotic analysis of the biharmonic elastic equation…

Soft Condensed Matter · Physics 2018-07-31 Chopin Julien , Panaitescu Andreea , Kudrolli Arshad

The static stress needed to depin a 2D edge dislocation, the lower dynamic stress needed to keep it moving, its velocity and displacement vector profile are calculated from first principles. We use a simplified discrete model whose far…

Materials Science · Physics 2009-11-10 A. Carpio , L. L. Bonilla

The interaction between carbon and screw dislocations in tungsten is investigated using ab initio calculations. The presence of carbon atoms in the vicinity of the dislocation induces a reconstruction, with the dislocation relaxing to a…

Materials Science · Physics 2021-06-14 Guillaume Hachet , Lisa Ventelon , François Willaime , Emmanuel Clouet

Dipolar dislocation loops, prevalent in fcc metals, are widely recognized as controlling many physical aspects of plastic deformation. We present results of 3D dislocation dynamics simulations that shed light on the mechanisms of their…

Materials Science · Physics 2017-01-02 Can Erel , Giacomo Po , Tamer Crosby , Nasr Ghoniem

Strain hardening is a key feature observed in many rocks deformed in the so-called ``semi-brittle'' regime, where both crystal plastic and brittle deformation mechanisms operate. Dislocation storage has long been recognised as a major…

Geophysics · Physics 2025-02-14 Nicolas Brantut