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Related papers: First-principles study of $\langle c+a \rangle$ di…

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Plasticity in hexagonal close packed (HCP) metals and alloys such as Titanium (Ti) and Zirconium (Zr) is carried out by the motion of $\langle a \rangle$ dislocations. Above room temperature, in situ transmission electron microscopy…

Materials Science · Physics 2023-10-25 Ali Rida , Satish I. Rao , Jaafar A. El-Awady

Plasticity in hexagonal close-packed zirconium is mainly controlled by the glide of dislocations with 1/3<1-210> Burgers vectors. As these dislocations cannot accommodate deformation in the [0001] direction , twinning or glide of <c+a>…

Materials Science · Physics 2020-09-07 Thomas Soyez , Daniel Caillard , Fabien Onimus , Emmanuel Clouet

The infuences of hydrogen on the generalized stacking fault (GSF) energies of the basal plane along the <10-10> and <11-20> directions in the hcp Zr were investigated using the first-principles calculation method. The modifications of the…

Computational Physics · Physics 2015-12-15 Hou Songjun , Lei Huaping , Zeng Zhi

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

In general, the cross-slip of superdislocations (a/2<011>) from {111} planes to {001} planes has been frequently observed in superalloys, accompanied by the formation of an antiphase boundary (APB) and driven by thermal activation. However,…

Materials Science · Physics 2025-08-26 Zhida Liang , Fengxian Liu , Xin Liu , Yang Li , Yinan Cui , Florian Pyczak

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

Dislocations corresponding to a change of stacking in two-dimensional hexagonal bilayers, graphene and boron nitride, and associated with boundaries between commensurate domains are investigated using the two-chain Frenkel-Kontorova model…

Mesoscale and Nanoscale Physics · Physics 2016-06-14 Irina V. Lebedeva , Alexander V. Lebedev , Andrey M. Popov , Andrey A. Knizhnik

Strain and rotation fields of dislocations in monolayer graphene have been mapped in a recent experiment. These fields are finite everywhere and differ from those given by linear elasticity which does not consider rotation explicitly and…

Mesoscale and Nanoscale Physics · Physics 2012-07-25 L. L. Bonilla , A. Carpio

In this paper, we deduce a macroscopic strain gradient theory for plasticity from a model of discrete dislocations. We restrict our analysis to the case of a cylindrical symmetry for the crystal in exam, so that the mathematical formulation…

Mathematical Physics · Physics 2008-08-19 Adriana Garroni , Giovanni Leoni , Marcello Ponsiglione

In this work, using the framework of (three-dimensional) Eshelbian dislocation mechanics, we derive the $J$-, $M$-, and $L$-integrals of a single (edge and screw) dislocation in isotropic elasticity as a limit of the $J$-, $M$-, and…

Materials Science · Physics 2020-08-25 Markus Lazar , Eleni Agiasofitou

We report on spin polarization reduction by incoherent tunneling in realistic single crystal Co2FeAl/MgO/Co50Fe50 magnetic tunnel junctions (MTJ) compared to reference Fe/MgO/Fe. A large density of misfit dislocations in the Heusler based…

Materials Science · Physics 2012-12-06 M. S. Gabor , C. Tiusan , T. Petrisor , T. Petrisor , M. Hehn , Y. Lu , E. Snoeck

We consider periodic piecewise affine functions, defined on the real line, with two given slopes and prescribed length scale of the regions where the slope is negative. We prove that, in such a class, the minimizers of $s$-fractional…

Analysis of PDEs · Mathematics 2022-07-13 Lucia De Luca , Marcello Ponsiglione , Emanuele Spadaro

In the limit of vanishing lattice spacing we provide a rigorous variational coarse-graining result for a next-to-nearest neighbor lattice model of a simple crystal. We show that the $\Gamma$-limit of suitable scaled versions of the model…

Analysis of PDEs · Mathematics 2024-07-08 Annika Bach , Marco Cicalese , Adriana Garroni , Gianluca Orlando

Dislocation core properties of tin (\beta-Sn) were investigated using the semi-discrete variational Peierls-Nabarro model (SVPN). The SVPN model, which connects the continuum elasticity treatment of the long-range strain field around a…

Materials Science · Physics 2017-03-08 M. A. Bhatia , M. Azarnoush , I. Adlakha , G. Lu , K. N. Solanki

A multiscale approach based on molecular dynamics (MD) and kinetic Monte Carlo (kMC) methods is developed to simulate the dynamics of an $\langle \mathbf{a} \rangle$ screw dislocation in $\alpha$-Ti. The free energy barriers for the core…

Materials Science · Physics 2023-12-22 Anwen Liu , Tongqi Wen , Jian Han , David J. Srolovitz

In this work the influence of $5|7$ dislocations in multiplayer graphene stacks (up to six layers) is examined. The study is conducted through a recently developed Phase Field Crystal (PFC) model for multilayer systems incorporating…

Materials Science · Physics 2024-10-04 K. R. Elder , Zhi-Feng Huang , T. Ala-Nissila

In the first part of this paper, a review is given on the mechanism for the disappearance of an intrinsic stacking fault in a hard-sphere (HS) crystal under gravity, which we recently discovered by Monte Carlo (MC) simulations [A. Mori et…

Soft Condensed Matter · Physics 2015-05-13 Atsushi Mori , Yoshihisa Suzuki , Shikegi Matsuo

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…

Whereas disclination defects are energetically prohibitive in two-dimensional flat crystals, their existence is necessary in crystals with spherical topology, such as viral capsids, colloidosomes or fullerenes. Such a geometrical…

Soft Condensed Matter · Physics 2020-07-01 Ireth García-Aguilar , Piermarco Fonda , Luca Giomi

Pinning of dislocations at nanosized obstacles like precipitates, voids and bubbles, is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often explored…

Materials Science · Physics 2014-10-22 A. Dutta , M. Bhattacharya , P. Barat