English
Related papers

Related papers: Free energy function of dislocation densities by l…

200 papers

Continuum models of dislocation plasticity require constitutive closure assumptions, e.g., by relating details of the dislocation microstructure to energy densities. Currently, there is no systematic way for deriving or extracting such…

Materials Science · Physics 2021-05-26 Hengxu Song , Nina Gunkelmann , Giacomo Po , Stefan Sandfeld

Because of the enormous range of time and space scales involved in dislocation dynamics, plastic modeling at macroscale requires a continuous formulation. In this paper, we present a rigorous formulation of the transition between the…

Materials Science · Physics 2016-06-22 P. L. Valdenaire , Y. Le Bouar , B. Appolaire , A. Finel

The elastic energy functional of a system of discrete dislocation lines is well known from dislocation theory. In this paper we demonstrate how the discrete functional can be used to systematically derive approximations which express the…

Materials Science · Physics 2015-12-02 Michael Zaiser

The continuum dislocation dynamics framework for mesoscale plasticity is intended to capture the dislocation density evolution and the deformation of crystals when subjected to mechanical loading. It does so by solving a set of transport…

Materials Science · Physics 2021-02-24 Vignesh Vivekanandan , Peng Lin , Grethe Winther , Anter El-Azab

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

The universality class of the avalanche behavior in plastically deforming crystalline and amorphous systems has been commonly discussed, despite the fact that the microscopic defect character in each of these systems is different. In…

Materials Science · Physics 2019-05-08 Hengxu Song , Dennis Dimiduk , Stefanos Papanikolaou

The efficiency of soft particles to stabilize emulsions is examined by measuring their desorption free energy, i.e., the mechanical work required to detach the particle from a fluid interface. Here, we consider rubber-like elastic as well…

Soft Condensed Matter · Physics 2020-08-20 Hadi Mehrabian , Jacco H. Snoeijer , Jens Harting

The expression of the free energy of a liquid in terms of an explicit decomposition of the particle configurations into local coordination clusters is examined. We argue that the major contribution to the entropy associated with structural…

Soft Condensed Matter · Physics 2016-06-10 Pierre Ronceray , Peter Harrowell

The continuum theory of dislocations, as developed predominantly by Kr\"oner and Kosevich, views each dislocation as a source of incompatibility of strains. We show that this concept can be employed efficiently in the Landau free energy…

Materials Science · Physics 2010-07-19 R. Gröger , T. Lookman

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

This work rigorously implements a recent model of large-strain elasto-plastic evolution in single crystals where the plastic flow is driven by the movement of discrete dislocation lines. The model is geometrically and elastically nonlinear,…

Analysis of PDEs · Mathematics 2024-02-27 Filip Rindler

We incorporate the role of free volume in the density function of the amorphous structure and study its effects on the stability of such structures. The Density Functional Theory is used to explore this ``Free Volume Model'' of the…

Statistical Mechanics · Physics 2009-11-07 Charanbir kaur , Shankar P. Das

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

A phenomenological model of the evolution of an ensemble of interacting dislocations in an isotropic elastic medium is formulated. The line-defect microstructure is described in terms of a spatially coarse-grained order parameter, the…

mtrl-th · Physics 2009-10-30 J. M. Rickman , Jorge Vinals

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

In continuum models of dislocations, proper formulations of short-range elastic interactions of dislocations are crucial for capturing various types of dislocation patterns formed in crystalline materials. In this article, the continuum…

Materials Science · Physics 2016-08-12 Yichao Zhu , Xiaohua Niu , Yang Xiang

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

Crystal plasticity of sub-micron finite volumes is characterized by the flow of emergent dislocation defects, giving rise to size effects in mechanical properties and avalanche phenomena. In this chapter, we present a minimal model for…

Materials Science · Physics 2019-08-09 Stefanos Papanikolaou , Michail Tzimas

Understanding the spontaneous emergence of dislocation patterns during plastic deformation is a long standing challenge in dislocation theory. During the past decades several phenomenological continuum models of dislocation patterning were…

Materials Science · Physics 2016-06-22 Istvan Groma , Michael Zaiser , Peter Dusan Ispanovity

We derive a continuum-level plasticity model for polycrystalline materials in the high energy density regime, based on a single dislocation density and single mobility mechanism, with an evolution model for the dislocation density. The…

‹ Prev 1 2 3 10 Next ›