scholarly journals Mean-Field Description of Plastic Flow in Amorphous Solids

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Jie Lin ◽  
Matthieu Wyart
Keyword(s):  
Plastic Flow ◽  
Mean Field ◽  
Amorphous Solids

scholarly journals Continuum limit of the vibrational properties of amorphous solids

2017 ◽  
Vol 114 (46) ◽  
pp. E9767-E9774 ◽  
Author(s):  
Hideyuki Mizuno ◽  
Hayato Shiba ◽  
Atsushi Ikeda
Keyword(s):  
Large Scale ◽  
Continuum Limit ◽  
Scaling Law ◽  
Mean Field ◽  
Low Frequency ◽  
Amorphous Solids ◽  
Mode Analysis ◽  
Vibrational Modes ◽  
Phonon Modes ◽  
The Continuum

The low-frequency vibrational and low-temperature thermal properties of amorphous solids are markedly different from those of crystalline solids. This situation is counterintuitive because all solid materials are expected to behave as a homogeneous elastic body in the continuum limit, in which vibrational modes are phonons that follow the Debye law. A number of phenomenological explanations for this situation have been proposed, which assume elastic heterogeneities, soft localized vibrations, and so on. Microscopic mean-field theories have recently been developed to predict the universal non-Debye scaling law. Considering these theoretical arguments, it is absolutely necessary to directly observe the nature of the low-frequency vibrations of amorphous solids and determine the laws that such vibrations obey. Herein, we perform an extremely large-scale vibrational mode analysis of a model amorphous solid. We find that the scaling law predicted by the mean-field theory is violated at low frequency, and in the continuum limit, the vibrational modes converge to a mixture of phonon modes that follow the Debye law and soft localized modes that follow another universal non-Debye scaling law.

scholarly journals Criticality in elastoplastic models of amorphous solids with stress-dependent yielding rates

Soft Matter ◽  
2019 ◽  
Vol 15 (44) ◽  
pp. 9041-9055 ◽  
Author(s):  
E. E. Ferrero ◽  
E. A. Jagla
Keyword(s):  
Critical Exponents ◽  
Mean Field ◽  
Amorphous Solids ◽  
Stress Dependent ◽  
Local Yielding

Elastoplastic models are analyzed at the yielding transition. Universality and critical exponents are discussed. The flowcurve exponent happens to be sensitive to the local yielding rule. An alternative mean-field description of yielding is explained.

scholarly journals Impact of jamming criticality on low-temperature anomalies in structural glasses

2019 ◽  
Vol 116 (28) ◽  
pp. 13768-13773 ◽  
Author(s):  
Silvio Franz ◽  
Thibaud Maimbourg ◽  
Giorgio Parisi ◽  
Antonello Scardicchio
Keyword(s):  
Low Temperature ◽  
Specific Heat ◽  
Field Model ◽  
Analytic Solution ◽  
Mean Field ◽  
Universality Class ◽  
Amorphous Solids ◽  
Anomalous Behavior ◽  
Marginal Stability ◽  
Mean Field Model

We present a mechanism for the anomalous behavior of the specific heat in low-temperature amorphous solids. The analytic solution of a mean-field model belonging to the same universality class as high-dimensional glasses, the spherical perceptron, suggests that there exists a cross-over temperature above which the specific heat scales linearly with temperature, while below it, a cubic scaling is displayed. This relies on two crucial features of the phase diagram: (i) the marginal stability of the free-energy landscape, which induces a gapless phase responsible for the emergence of a power-law scaling; and (ii) the vicinity of the classical jamming critical point, as the cross-over temperature gets lowered when approaching it. This scenario arises from a direct study of the thermodynamics of the system in the quantum regime, where we show that, contrary to crystals, the Debye approximation does not hold.

Brittle and Ductile Character of Amorphous Solids

2016 ◽  
Vol 8 (3) ◽  
pp. 485-498
Author(s):  
Miguel Lagos ◽  
Raj Das
Keyword(s):  
Glass Transition ◽  
Plastic Flow ◽  
Metallic Glasses ◽  
Bulk Material ◽  
Amorphous Solids ◽  
Amorphous Structure ◽  
Atomic Scale ◽  
Brittle Solid ◽  
Disordered Structure ◽  
The Difference

Abstract.Common silicate glasses are among the most brittle of the materials. However, on warming beyond the glass transition temperature Tg glass transforms into one of the most plastic known materials. Bulk metallic glasses exhibit similar phenomenology, indicating that it rests on the disordered structure instead on the nature of the chemical bonds. The micromechanics of a solid with bulk amorphous structure is examined in order to determine the most basic conditions the system must satisfy to be able of plastic flow. The equations for the macroscopic flow, consistent with the constrictions imposed at the atomic scale, prove that a randomly structured bulk material must be either a brittle solid or a liquid, but not a ductile solid. The theory permits to identify a single parameter determining the difference between the brittle solid and the liquid. However, the system is able of perfect ductility if the plastic flow proceeds in two dimensional plane layers that concentrate the strain. Insight is gained on the nature of the glass transition, and the phase occurring between glass transition and melting.

Residual stress distributions in amorphous solids from atomistic simulations

Soft Matter ◽  
2020 ◽  
Vol 16 (38) ◽  
pp. 8940-8949
Author(s):  
Céline Ruscher ◽  
Jörg Rottler
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Plastic Flow ◽  
Amorphous Solids ◽  
Atomistic Simulations ◽  
Stress Distributions

The distribution of local residual stresses that controls the properties of plastic flow in athermal amorphous solids is examined with atomistic simulations revealing that deviation from a pseudogap form appears after few percentages of deformation.

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