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Divoux T, Agoritsas E, Aime S, Barentin C, Barrat JL, Benzi R, Berthier L, Bi D, Biroli G, Bonn D, Bourrianne P, Bouzid M, Del Gado E, Delanoë-Ayari H, Farain K, Fielding S, Fuchs M, van der Gucht J, Henkes S, Jalaal M, Joshi YM, Lemaître A, Leheny RL, Manneville S, Martens K, Poon WCK, Popović M, Procaccia I, Ramos L, Richards JA, Rogers S, Rossi S, Sbragaglia M, Tarjus G, Toschi F, Trappe V, Vermant J, Wyart M, Zamponi F, Zare D. Ductile-to-brittle transition and yielding in soft amorphous materials: perspectives and open questions. SOFT MATTER 2024. [PMID: 39028363 DOI: 10.1039/d3sm01740k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Soft amorphous materials are viscoelastic solids ubiquitously found around us, from clays and cementitious pastes to emulsions and physical gels encountered in food or biomedical engineering. Under an external deformation, these materials undergo a noteworthy transition from a solid to a liquid state that reshapes the material microstructure. This yielding transition was the main theme of a workshop held from January 9 to 13, 2023 at the Lorentz Center in Leiden. The manuscript presented here offers a critical perspective on the subject, synthesizing insights from the various brainstorming sessions and informal discussions that unfolded during this week of vibrant exchange of ideas. The result of these exchanges takes the form of a series of open questions that represent outstanding experimental, numerical, and theoretical challenges to be tackled in the near future.
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Affiliation(s)
- Thibaut Divoux
- ENSL, CNRS, Laboratoire de physique, F-69342 Lyon, France.
| | - Elisabeth Agoritsas
- Department of Quantum Matter Physics (DQMP), University of Geneva, Quai Ernest-Ansermet 24, CH-1211 Geneva, Switzerland
| | - Stefano Aime
- Molecular, Macromolecular Chemistry, and Materials, ESPCI Paris, Paris, France
| | - Catherine Barentin
- Univ. de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622 Villeurbanne, France
| | - Jean-Louis Barrat
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Roberto Benzi
- Department of Physics & INFN, Tor Vergata University of Rome, Via della Ricerca Scientifica 1, 00133, Rome, Italy
| | - Ludovic Berthier
- Laboratoire Charles Coulomb (L2C), Université Montpellier, CNRS, Montpellier, France
| | - Dapeng Bi
- Department of Physics, Northeastern University, Boston, MA 02115, USA
| | - Giulio Biroli
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
| | - Daniel Bonn
- Soft Matter Group, van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands
| | - Philippe Bourrianne
- PMMH, CNRS, ESPCI Paris, Université PSL, Sorbonne Université, Université Paris Cité, Paris, France
| | - Mehdi Bouzid
- Univ. Grenoble Alpes, CNRS, Grenoble INP, 3SR, F-38000 Grenoble, France
| | - Emanuela Del Gado
- Georgetown University, Department of Physics, Institute for Soft Matter Synthesis and Metrology, Washington, DC, USA
| | - Hélène Delanoë-Ayari
- Univ. de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622 Villeurbanne, France
| | - Kasra Farain
- Soft Matter Group, van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands
| | - Suzanne Fielding
- Department of Physics, Durham University, South Road, Durham DH1 3LE, UK
| | - Matthias Fuchs
- Fachbereich Physik, Universität Konstanz, 78457 Konstanz, Germany
| | - Jasper van der Gucht
- Physical Chemistry and Soft Matter, Wageningen University & Research, Stippeneng 4, 6708WE Wageningen, The Netherlands
| | - Silke Henkes
- Lorentz Institute, Leiden University, 2300 RA Leiden, The Netherlands
| | - Maziyar Jalaal
- Institute of Physics, University of Amsterdam, Science Park 904, Amsterdam, The Netherlands
| | - Yogesh M Joshi
- Department of Chemical Engineering, Indian Institute of Technology, Kanpur 208016, Uttar Pradesh, India
| | - Anaël Lemaître
- Navier, École des Ponts, Univ Gustave Eiffel, CNRS, Marne-la-Vallée, France
| | - Robert L Leheny
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | | | | | - Wilson C K Poon
- SUPA and the School of Physics and Astronomy, The University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, UK
| | - Marko Popović
- Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Str.38, 01187 Dresden, Germany
| | - Itamar Procaccia
- Dept. of Chemical Physics, The Weizmann Institute of Science, Rehovot 76100, Israel
- Sino-Europe Complex Science Center, School of Mathematics, North University of China, Shanxi, Taiyuan 030051, China
| | - Laurence Ramos
- Laboratoire Charles Coulomb (L2C), Université Montpellier, CNRS, Montpellier, France
| | - James A Richards
- SUPA and the School of Physics and Astronomy, The University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, UK
| | - Simon Rogers
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Saverio Rossi
- LPTMC, CNRS-UMR 7600, Sorbonne Université, 4 Pl. Jussieu, F-75005 Paris, France
| | - Mauro Sbragaglia
- Department of Physics & INFN, Tor Vergata University of Rome, Via della Ricerca Scientifica 1, 00133, Rome, Italy
| | - Gilles Tarjus
- LPTMC, CNRS-UMR 7600, Sorbonne Université, 4 Pl. Jussieu, F-75005 Paris, France
| | - Federico Toschi
- Department of Applied Physics and Science Education, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
- CNR-IAC, Via dei Taurini 19, 00185 Rome, Italy
| | - Véronique Trappe
- Department of Physics, University of Fribourg, Chemin du Musée 3, Fribourg 1700, Switzerland
| | - Jan Vermant
- Department of Materials, ETH Zürich, Vladimir Prelog Weg 5, 8032 Zürich, Switzerland
| | - Matthieu Wyart
- Department of Quantum Matter Physics (DQMP), University of Geneva, Quai Ernest-Ansermet 24, CH-1211 Geneva, Switzerland
| | - Francesco Zamponi
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, F-75005 Paris, France
- Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Davoud Zare
- Fonterra Research and Development Centre, Dairy Farm Road, Fitzherbert, Palmerston North 4442, New Zealand
- Nestlé Institute of Food Sciences, Nestlé Research, Vers Chez les Blancs, Lausanne, Switzerland
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2
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Jagla EA. From shear bands to earthquakes in a model granular material with contact aging. SOFT MATTER 2024; 20:588-598. [PMID: 38131393 DOI: 10.1039/d3sm01427d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
We perform molecular dynamics simulations of homogeneous athermal systems of poly-disperse soft discs under shear. For purely repulsive interactions between particles, and under a confining external pressure, a monotonous flow curve (strain rate vs. stress) starting at a critical yield stress is obtained, with deformation distributing uniformly in the system, on average. Then we add a short range attractive contribution to the interaction potential that increases its intensity as particles remain in contact for a progressively longer time, mimicking an aging effect in the system. In this case the flow curve acquires a reentrant behavior, namely, a region where shear stress decreases with increasing strain. Within this region the deformation is seen to localize in a shear band with a well defined width that decreases as the global strain rate does. At very low strain rates the shear band becomes very thin and deformation acquires a prominent stick-slip behavior. This regime can be described as the system possessing a fault in which deformation occurs with an earthquake-resembling phenomenology. In this way the system we are analyzing connects a regime of uniform deformation at large strain rates, a localized deformation regime in the form of shear bands at intermediate stain rates, and seismic phenomena at very low strain rate. The unifying ingredient of this phenomenology is the existence of a reentrant flow curve, originating in the aging mechanisms present in the model.
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Affiliation(s)
- E A Jagla
- Centro Atómico Bariloche, Instituto Balseiro, Comisión Nacional de Energía Atómica, CNEA, CONICET, UNCUYO, Av. E. Bustillo 9500 (R8402AGP), San Carlos de Bariloche, Río Negro, Argentina
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Vasisht VV, Goff ML, Martens K, Barrat JL. Permanent shear localization in dense disordered materials due to microscopic inertia. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2023; 46:106. [PMID: 37917357 DOI: 10.1140/epje/s10189-023-00367-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 10/13/2023] [Indexed: 11/04/2023]
Abstract
In this work using computer simulations of 3D model of dense disordered solids we show, for the first time, the appearance of shear localization in the stationary flow under homogeneous driving conditions. To rationalize our simulation results we develop a continuum model, that couples the dynamics of the local flow to the evolution of a kinetic temperature field related to the local inertial dynamics. Our model predicts that the coupling of the flow field to this additional destabilizing field appears only as a necessary condition for shear localization, a minimum system size is necessary to accommodate the flow instability. Moreover we show that this size criterion resulting from our continuum description is in quantitative agreement with our particle-based simulation results.
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Affiliation(s)
- Vishwas V Vasisht
- Department of Physics, Indian Institute of Technology, Palakkad, 678623, India
| | - Magali Le Goff
- CNRS, LIPhy, University Grenoble Alpes, 38000, Grenoble, France
| | - Kirsten Martens
- CNRS, LIPhy, University Grenoble Alpes, 38000, Grenoble, France
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Lalieu J, Seguin A, Gauthier G. Rheology of granular rafts. Phys Rev E 2023; 107:064901. [PMID: 37464614 DOI: 10.1103/physreve.107.064901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 06/15/2023] [Indexed: 07/20/2023]
Abstract
Rheology of macroscopic particle-laden interfaces, called "granular rafts," has been experimentally studied in the simple shear configuration. The shear-stress relation obtained from a classical rheometer exhibits the same behavior as a Bingham fluid, and the viscosity diverges with the surface fraction according to evolutions similar to 2D suspensions. The velocity field of the particles that constitute the granular raft has been measured in the stationary state. These measurements reveal nonlocal rheology similar to dry granular materials. Close to the walls of the rheometer cell, one can observe regions of large local shear rate while in the middle of the cell a quasistatic zone exists. This flowing region, characteristic of granular matter, is described in the framework of an extended kinetic theory showing the evolution of the velocity profile with the imposed shear stress. Measuring the probability density functions of the instantaneous local shear rate, we provide evidence of a balance between positive and negative instantaneous local shear rate. This behavior is the signature of a quasistatic region inside the granular raft.
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Affiliation(s)
- J Lalieu
- Université Paris-Saclay, CNRS, Laboratoire FAST, F-91405 Orsay, France
| | - A Seguin
- Université Paris-Saclay, CNRS, Laboratoire FAST, F-91405 Orsay, France
| | - G Gauthier
- Université Paris-Saclay, CNRS, Laboratoire FAST, F-91405 Orsay, France
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Lamp K, Küchler N, Horbach J. Brittle yielding in supercooled liquids below the critical temperature of mode coupling theory. J Chem Phys 2022; 157:034501. [DOI: 10.1063/5.0086626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Molecular dynamics computer simulations of a polydisperse soft-sphere model under shear are presented. The starting point for these simulations are deeply supercooled samples far below the critical temperature, T c, of mode coupling theory. These samples are fully equilibrated with the aid of the swap Monte Carlo technique. For states below T c, we identify a lifetime τlt that measures the time scale on which the system can be considered as an amorphous solid. The temperature dependence of τlt can be well described by an Arrhenius law. The existence of transient amorphous solid states below T c is associated with the possibility of brittle yielding, as manifested by a sharp stress drop in the stress–strain relation and shear banding. We show that brittle yielding requires, on the one hand, low shear rates and, on the other hand, the time scale corresponding to the inverse shear rate has to be smaller or of the order of τlt. Both conditions can only be met for a large lifetime τlt, i.e., for states far below T c.
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Affiliation(s)
- Konstantin Lamp
- Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Niklas Küchler
- Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Jürgen Horbach
- Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
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6
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Villarroel C, Düring G. Critical yielding rheology: from externally deformed glasses to active systems. SOFT MATTER 2021; 17:9944-9949. [PMID: 34693958 DOI: 10.1039/d1sm00948f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We use extensive computer simulations to study the yielding transition under two different loading schemes: standard simple shear dynamics and self-propelled dense active systems. In the active systems, a yielding transition toward an out-of-equilibrium flowing state known as the liquid phase is observed when self-propulsion is increased. The range of self-propulsions in which this pure liquid regime exists appears to vanish upon approaching the so-called 'jamming point' at which the solidity of soft-sphere packings is lost. Such an 'active yielding' transition shares similarities with the generic yielding transition for shear flows. A Herschel-Bulkley law is observed along the liquid regime in both loading scenarios, with a clear difference in the critical scaling exponents between the two, suggesting the existence of different universality classes for the yielding transition under different driving conditions. In addition, we present the direct measurements of growing length and time scales for both driving scenarios. A comparison with theoretical predictions from the recent literature reveals poor agreement with our numerical results.
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Affiliation(s)
- Carlos Villarroel
- Instituto de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago, Chile.
| | - Gustavo Düring
- Instituto de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago, Chile.
- ANID - Millenium Nucleus of Soft Smart Mechanical Metamaterials, Santiago, Chile
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Shrivastav GP, Kahl G. On the yielding of a point-defect-rich model crystal under shear: insights from molecular dynamics simulations. SOFT MATTER 2021; 17:8536-8552. [PMID: 34505613 PMCID: PMC8480408 DOI: 10.1039/d1sm00662b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 08/31/2021] [Indexed: 06/13/2023]
Abstract
In real crystals and at finite temperatures point defects are inevitable. Under shear their dynamics severely influence the mechanical properties of these crystals, giving rise to non-linear effects, such as ductility. In an effort to elucidate the complex behavior of crystals under plastic deformation it is crucial to explore and to understand the interplay between the timescale related to the equilibrium point-defect diffusion and the shear-induced timescale. Based on extensive non-equilibrium molecular dynamics simulations we present a detailed investigation on the yielding behavior of cluster crystals, an archetypical model for a defect-rich crystal: in such a system clusters of overlapping particles occupy the lattice sites of a regular (FCC) structure. In equilibrium particles diffuse via site-to-site hopping while maintaining the crystalline structure intact. We investigate these cluster crystals at a fixed density and at different temperatures where the system remains in the FCC structure: temperature allows us to vary the diffusion timescale appropriately. We then expose the crystal to shear, thereby choosing shear rates which cover timescales that are both higher and lower than the equilibrium diffusion timescales. We investigate the macroscopic and microscopic response of our cluster crystal to shear and find that the yielding scenario of such a system does not rely on the diffusion of the particles - it is rather related to the plastic deformation of the underlying crystalline structure. The local bond order parameters and the measurement of local angles between neighboring clusters confirm the cooperative movement of the clusters close to the yield point. Performing complementary, related simulations for an FCC crystal formed by harshly repulsive particles reveals similarities in the yielding behavior between both systems. Still we find that the diffusion of particles does influence characteristic features in the cluster crystal, such as a less prominent increase of order parameters close to the yield point. Our simulations provide for the first time an insight into the role of the diffusion of defects in the yielding behavior of a defect-rich crystal under shear. These observations will thus be helpful in the development of theories for the plastic deformation of defect-rich crystals.
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Affiliation(s)
- Gaurav P Shrivastav
- Institut für Theoretische Physik and Center for Computational Materials Science (CMS), TU Wien, Wiedner Hauptstraße 8-10, A-1040 Wien, Austria.
| | - Gerhard Kahl
- Institut für Theoretische Physik and Center for Computational Materials Science (CMS), TU Wien, Wiedner Hauptstraße 8-10, A-1040 Wien, Austria.
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Clemmer JT, Salerno KM, Robbins MO. Criticality in sheared, disordered solids. I. Rate effects in stress and diffusion. Phys Rev E 2021; 103:042605. [PMID: 34005889 DOI: 10.1103/physreve.103.042605] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 03/16/2021] [Indexed: 11/07/2022]
Abstract
Rate effects in sheared disordered solids are studied using molecular dynamics simulations of binary Lennard-Jones glasses in two and three dimensions. In the quasistatic (QS) regime, systems exhibit critical behavior: the magnitudes of avalanches are power-law distributed with a maximum cutoff that diverges with increasing system size L. With increasing rate, systems move away from the critical yielding point and the average flow stress rises as a power of the strain rate with exponent 1/β, the Herschel-Bulkley exponent. Finite-size scaling collapses of the stress are used to measure β as well as the exponent ν which characterizes the divergence of the correlation length. The stress and kinetic energy per particle experience fluctuations with strain that scale as L^{-d/2}. As the largest avalanche in a system scales as L^{α}, this implies α<d/2. The diffusion rate of particles diverges as a power of decreasing rate before saturating in the QS regime. A scaling theory for the diffusion is derived using the QS avalanche rate distribution and generalized to the finite strain rate regime. This theory is used to collapse curves for different system sizes and confirm β/ν.
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Affiliation(s)
- Joel T Clemmer
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | | | - Mark O Robbins
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
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9
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Golovkova I, Montel L, Pan F, Wandersman E, Prevost AM, Bertrand T, Pontani LL. Adhesion as a trigger of droplet polarization in flowing emulsions. SOFT MATTER 2021; 17:3820-3828. [PMID: 33725054 DOI: 10.1039/d1sm00097g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Tissues are subjected to large external forces and undergo global deformations during morphogenesis. We use synthetic analogues of tissues to study the impact of cell-cell adhesion on the response of cohesive cellular assemblies under such stresses. In particular, we use biomimetic emulsions in which the droplets are functionalized in order to exhibit specific droplet-droplet adhesion. We flow these emulsions in microfluidic constrictions and study their response to this forced deformation via confocal microscopy. We find that the distributions of avalanche sizes are conserved between repulsive and adhesive droplets. However, adhesion locally impairs the rupture of droplet-droplet contacts, which in turn pulls on the rearranging droplets. As a result, adhesive droplets are a lot more deformed along the axis of elongation in the constriction. This finding could shed light on the origin of polarization processes during morphogenesis.
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Affiliation(s)
- Iaroslava Golovkova
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), F-75005, Paris, France.
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10
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Liu C, Dutta S, Chaudhuri P, Martens K. Elastoplastic Approach Based on Microscopic Insights for the Steady State and Transient Dynamics of Sheared Disordered Solids. PHYSICAL REVIEW LETTERS 2021; 126:138005. [PMID: 33861121 DOI: 10.1103/physrevlett.126.138005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 02/26/2021] [Indexed: 06/12/2023]
Abstract
We develop a framework to study the mechanical response of athermal amorphous solids via a coupling of mesoscale and microscopic models. Using measurements of coarse-grained quantities from simulations of dense disordered particulate systems, we present a coherent elastoplastic model approach for deformation and flow of yield stress materials. For a given set of parameters, this model allows us to match consistently transient and steady state features of driven disordered systems with diverse preparation histories under both applied shear-rate and creep protocols.
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Affiliation(s)
- Chen Liu
- Laboratoire de Physique de l'Ecole Normale Suprieure, 75005 Paris, France
| | - Suman Dutta
- The Institute of Mathematical Sciences, Taramani, Chennai 600113, India
| | - Pinaki Chaudhuri
- The Institute of Mathematical Sciences, Taramani, Chennai 600113, India
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11
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Mandal S, Gans A, Nicolas M, Pouliquen O. Flows of cohesive granular media. EPJ WEB OF CONFERENCES 2021. [DOI: 10.1051/epjconf/202124901001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Cohesive granular media have broad applications in industries. However, our understanding of their flow behavior is still limited compared to dry granular media, although rich knowledge about their static and plastic properties has been gained. In this paper, we provide some insights into the flow behavior of cohesive granular media from our recent numerical studies using an inclined plane and a plane shear cell. We evidence that the cohesive nature of flows is significantly affected by material properties of the particles like stiffness and inelasticity in addition to the inter-particle adhesion and introduce the concept of “effective” adhesion, which incorporates the effects of these three variables. We propose constitutive relations involving dimensionless inertial number and “effective” cohesion number, based on the “effective” adhesion to describe the rheology. We also show that increasing adhesion increases the hysteresis in granular media, evidencing the existence of a prominent shear weakening branch in the friction coefficient versus inertial number rheological curve. Moreover, we reveal that this increasing hysteresis gives rise to the increasing occurrence of shear banding instability, pointing to the increasing possibility of jamming in cohesive granular media. Finally, we present a promising experimental approach to investigate the flow behavior of cohesive granular materials, based on a simple method of preparing a long time stable medium with a controlled adhesion between particles.
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12
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Liberto T, Le Merrer M, Manneville S, Barentin C. Interparticle attraction controls flow heterogeneity in calcite gels. SOFT MATTER 2020; 16:9217-9229. [PMID: 32926058 DOI: 10.1039/d0sm01079k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We couple rheometry and ultrasonic velocimetry to study experimentally the flow behavior of gels of colloidal calcite particles dispersed in water, while tuning the strength of the interparticle attraction through physico-chemistry. We unveil, for the first time in a colloidal gel, a direct connection between attractive interactions and the occurrence of shear bands, as well as stress fluctuations.
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Affiliation(s)
- Teresa Liberto
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France. and Institute of Materials Technology, Building Physics and Construction Ecology, Faculty of Civil Engineering, Vienna University of Technology, Karlsplatz 13, 1040 Vienna, Austria
| | - Marie Le Merrer
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France.
| | - Sébastien Manneville
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS, Laboratoire de Physique, F-69342 Lyon, France
| | - Catherine Barentin
- Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, Villeurbanne, France. and Institut Universitaire de France, France
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13
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Golkia M, Shrivastav GP, Chaudhuri P, Horbach J. Flow heterogeneities in supercooled liquids and glasses under shear. Phys Rev E 2020; 102:023002. [PMID: 32942371 DOI: 10.1103/physreve.102.023002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 07/28/2020] [Indexed: 11/07/2022]
Abstract
Using extensive nonequilibrium molecular dynamics simulations, we investigate a glass-forming binary Lennard-Jones mixture under shear. Both supercooled liquids and glasses are considered. Our focus is on the characterization of inhomogeneous flow patterns such as shear bands that appear as a transient response to the external shear. For the supercooled liquids, we analyze the crossover from Newtonian to non-Newtonian behavior with increasing shear rate γ[over ̇]. Above a critical shear rate γ[over ̇]_{c} where a non-Newtonian response sets in, the transient dynamics are associated with the occurrence of short-lived vertical shear bands, i.e., bands of high mobility that form perpendicular to the flow direction. In the glass states, long-lived horizontal shear bands, i.e., bands of high mobility parallel to the flow direction, are observed in addition to vertical ones. The systems with shear bands are characterized in terms of mobility maps, stress-strain relations, mean-squared displacements, and (local) potential energies. The initial formation of a horizontal shear band provides an efficient stress release, corresponds to a local minimum of the potential energy, and is followed by a slow broadening of the band towards the homogeneously flowing fluid in the steady state. Whether a horizontal or a vertical shear band forms cannot be predicted from the initial undeformed sample. Furthermore, we show that with increasing system size, the probability for the occurrence of horizontal shear bands increases.
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Affiliation(s)
- Mehrdad Golkia
- Institut für Theoretische Physik II: Weiche Materie, Heinrich Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Gaurav P Shrivastav
- Institute for Theoretical Physics, TU Wien, Wiedner Hauptstraße 8-10, 1040 Wien, Austria
| | - Pinaki Chaudhuri
- The Institute of Mathematical Sciences, IV Cross Road, CIT Campus, Taramani, Chennai 600 113, Tamil Nadu, India
| | - Jürgen Horbach
- Institut für Theoretische Physik II: Weiche Materie, Heinrich Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
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14
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Vasisht VV, Del Gado E. Computational study of transient shear banding in soft jammed solids. Phys Rev E 2020; 102:012603. [PMID: 32795069 DOI: 10.1103/physreve.102.012603] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 05/29/2020] [Indexed: 11/07/2022]
Abstract
We have designed three-dimensional numerical simulations of a soft spheres model, with size polidispersity and in athermal conditions, to study the transient shear banding that occurs during yielding of jammed soft solids. We analyze the effects of different types of drag coefficients used in the simulations and compare the results obtained using Lees-Edwards periodic boundary conditions with the case in which the same model solid is confined between two walls. The specific damping mechanism and the different boundary conditions indeed modify the load curves and the velocity profiles in the transient regime. Nevertheless, we find that the presence of a stress overshoot and of a related transient banding phenomenon, for large enough samples, is a robust feature for overdamped systems, where their presence do not depend on the specific drag used and on the different boundary conditions.
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Affiliation(s)
- Vishwas V Vasisht
- Indian Institute of Technology Palakkad, Ahalia Integrated Campus, Kozhippara P.O. - Palakkad, Kerala 678557, India.,Department of Physics, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets, N.W., Washington, DC 20057, USA
| | - Emanuela Del Gado
- Department of Physics, Institute for Soft Matter Synthesis and Metrology, Georgetown University, 37th and O Streets, N.W., Washington, DC 20057, USA
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15
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Bhowmik BP, Chaudhuri P, Karmakar S. Effect of Pinning on the Yielding Transition of Amorphous Solids. PHYSICAL REVIEW LETTERS 2019; 123:185501. [PMID: 31763889 DOI: 10.1103/physrevlett.123.185501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Indexed: 06/10/2023]
Abstract
Using numerical simulations, we have studied the yielding response, in the athermal quasistatic limit, of a model amorphous material having inclusions in the form of randomly pinned particles. We show that, with increasing pinning concentration, the plastic activity becomes more spatially localized, resulting in smaller stress drops, and a corresponding increase in the magnitude of strain where yielding occurs. We demonstrate that, unlike the spatially heterogeneous and avalanche led yielding in the case of the unpinned glass, for the case of large pinning concentration, yielding takes place via a spatially homogeneous proliferation of localized events.
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Affiliation(s)
- Bhanu Prasad Bhowmik
- Tata Institute of Fundamental Research, 36/P, Gopanpally Village, Serilingampally Mandal, Ranga Reddy District, Hyderabad, 500107, Telangana, India
| | - Pinaki Chaudhuri
- Institute of Mathematical Sciences, IV Cross Road, CIT Campus, Taramani, Chennai, 600113, Tamil Nadu, India
| | - Smarajit Karmakar
- Tata Institute of Fundamental Research, 36/P, Gopanpally Village, Serilingampally Mandal, Ranga Reddy District, Hyderabad, 500107, Telangana, India
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16
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Varga Z, Grenard V, Pecorario S, Taberlet N, Dolique V, Manneville S, Divoux T, McKinley GH, Swan JW. Hydrodynamics control shear-induced pattern formation in attractive suspensions. Proc Natl Acad Sci U S A 2019; 116:12193-12198. [PMID: 31164423 PMCID: PMC6591707 DOI: 10.1073/pnas.1901370116] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dilute suspensions of repulsive particles exhibit a Newtonian response to flow that can be accurately predicted by the particle volume fraction and the viscosity of the suspending fluid. However, such a description fails when the particles are weakly attractive. In a simple shear flow, suspensions of attractive particles exhibit complex, anisotropic microstructures and flow instabilities that are poorly understood and plague industrial processes. One such phenomenon, the formation of log-rolling flocs, which is ubiquitously observed in suspensions of attractive particles that are sheared while confined between parallel plates, is an exemplar of this phenomenology. Combining experiments and discrete element simulations, we demonstrate that this shear-induced structuring is driven by hydrodynamic coupling between the flocs and the confining boundaries. Clusters of particles trigger the formation of viscous eddies that are spaced periodically and whose centers act as stable regions where particles aggregate to form flocs spanning the vorticity direction. Simulation results for the wavelength of the periodic pattern of stripes formed by the logs and for the log diameter are in quantitative agreement with experimental observations on both colloidal and noncolloidal suspensions. Numerical and experimental results are successfully combined by means of rescaling in terms of a Mason number that describes the strength of the shear flow relative to the rupture force between contacting particles in the flocs. The introduction of this dimensionless group leads to a universal stability diagram for the log-rolling structures and allows for application of shear-induced structuring as a tool for assembling and patterning suspensions of attractive particles.
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Affiliation(s)
- Zsigmond Varga
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Vincent Grenard
- Laboratoire de Physique, École Normale Supérieure de Lyon, Université Claude Bernard, Université de Lyon, CNRS, F-69342 Lyon, France
| | - Stefano Pecorario
- Laboratoire de Physique, École Normale Supérieure de Lyon, Université Claude Bernard, Université de Lyon, CNRS, F-69342 Lyon, France
| | - Nicolas Taberlet
- Laboratoire de Physique, École Normale Supérieure de Lyon, Université Claude Bernard, Université de Lyon, CNRS, F-69342 Lyon, France
| | - Vincent Dolique
- Laboratoire de Physique, École Normale Supérieure de Lyon, Université Claude Bernard, Université de Lyon, CNRS, F-69342 Lyon, France
| | - Sébastien Manneville
- Laboratoire de Physique, École Normale Supérieure de Lyon, Université Claude Bernard, Université de Lyon, CNRS, F-69342 Lyon, France
| | - Thibaut Divoux
- Centre de Recherche Paul Pascal, CNRS UMR 5031, 33600 Pessac, France
- MultiScale Material Science for Energy and Environment, Unité Mixte Internationale 3466, CNRS-Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Gareth H McKinley
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - James W Swan
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139;
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17
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Roy S, Scheper BJ, Polman H, Thornton AR, Tunuguntla DR, Luding S, Weinhart T. Surface flow profiles for dry and wet granular materials by Particle Tracking Velocimetry; the effect of wall roughness. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2019; 42:14. [PMID: 30756195 DOI: 10.1140/epje/i2019-11778-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Accepted: 01/04/2019] [Indexed: 06/09/2023]
Abstract
Two-dimensional Particle Tracking Velocimetry (PTV) is a promising technique to study the behaviour of granular flows. The aim is to experimentally determine the free surface width and position of the shear band from the velocity profile to validate simulations in a split-bottom shear cell geometry. The position and velocities of scattered tracer particles are tracked as they move with the bulk flow by analyzing images. We then use a new technique to extract the continuum velocity field, applying coarse-graining with the postprocessing toolbox MercuryCG on the discrete experimental PTV data. For intermediate filling heights, the dependence of the shear (or angular) velocity on the radial coordinate at the free surface is well fitted by an error function. From the error function, we get the width and the centre position of the shear band. We investigate the dependence of these shear band properties on filling height and rotation frequencies of the shear cell for dry glass beads for rough and smooth wall surfaces. For rough surfaces, the data agrees with the existing experimental results and theoretical scaling predictions. For smooth surfaces, particle-wall slippage is significant and the data deviates from the predictions. We further study the effect of cohesion on the shear band properties by using small amount of silicon oil and glycerol as interstitial liquids with the glass beads. While silicon oil does not lead to big changes, glycerol changes the shear band properties considerably. The shear band gets wider and is situated further inward with increasing liquid saturation, due to the correspondingly increasing trend of particles to stick together.
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Affiliation(s)
- Sudeshna Roy
- Multi-Scale Mechanics, Engineering Technology (ET) and MESA + University of Twente, 7500, AE Enschede, The Netherlands.
| | - Bert J Scheper
- Multi-Scale Mechanics, Engineering Technology (ET) and MESA + University of Twente, 7500, AE Enschede, The Netherlands
| | - Harmen Polman
- Multi-Scale Mechanics, Engineering Technology (ET) and MESA + University of Twente, 7500, AE Enschede, The Netherlands
| | - Anthony R Thornton
- Multi-Scale Mechanics, Engineering Technology (ET) and MESA + University of Twente, 7500, AE Enschede, The Netherlands
| | - Deepak R Tunuguntla
- Multi-Scale Mechanics, Engineering Technology (ET) and MESA + University of Twente, 7500, AE Enschede, The Netherlands
| | - Stefan Luding
- Multi-Scale Mechanics, Engineering Technology (ET) and MESA + University of Twente, 7500, AE Enschede, The Netherlands
| | - Thomas Weinhart
- Multi-Scale Mechanics, Engineering Technology (ET) and MESA + University of Twente, 7500, AE Enschede, The Netherlands
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18
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Koeze DJ, Tighe BP. Sticky Matters: Jamming and Rigid Cluster Statistics with Attractive Particle Interactions. PHYSICAL REVIEW LETTERS 2018; 121:188002. [PMID: 30444395 DOI: 10.1103/physrevlett.121.188002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Indexed: 06/09/2023]
Abstract
While the large majority of theoretical and numerical studies of the jamming transition consider athermal packings of purely repulsive spheres, real complex fluids and soft solids generically display attraction between particles. By studying the statistics of rigid clusters in simulations of soft particles with an attractive shell, we present evidence for two distinct jamming scenarios. Strongly attractive systems undergo a continuous transition in which rigid clusters grow and ultimately diverge in size at a critical packing fraction. Purely repulsive and weakly attractive systems jam via a first-order transition, with no growing cluster size. We further show that the weakly attractive scenario is a finite size effect, so that for any nonzero attraction strength, a sufficiently large system will fall in the strongly attractive universality class. We therefore expect attractive jamming to be generic in the laboratory and in nature.
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Affiliation(s)
- Dion J Koeze
- Delft University of Technology, Process & Energy Laboratory, Leeghwaterstraat 39, 2628 CB Delft, The Netherlands
| | - Brian P Tighe
- Delft University of Technology, Process & Energy Laboratory, Leeghwaterstraat 39, 2628 CB Delft, The Netherlands
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19
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Liu T, Khabaz F, Bonnecaze RT, Cloitre M. On the universality of the flow properties of soft-particle glasses. SOFT MATTER 2018; 14:7064-7074. [PMID: 30116807 DOI: 10.1039/c8sm01153b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We identify the minimal interparticle interactions necessary for a particle dynamics simulation to predict the structure and flow behaviour of soft particle glasses (SPGs). Generally, two kinds of forces between the particles must be accounted for in simulations of SPGs: viscous or frictional drag forces and elastic contact forces. Far field drag forces are required to dissipate energy in the simulations and capture the effect of the rheology of the suspending fluid. Elastic forces are found to be dominant compared to near-field drag or other forms of friction forces and are the most important component to compute the rheology. The shear stress, the first and second normal stress differences for different interparticle force laws collapse onto universal master curves of the Herschel-Bulkley form by non-dimensionalizing the stress with the yield stress and the shear rate with the viscosity of the suspending fluid divided by the low-frequency shear modulus. The Herschel-Bulkley exponents are close to 0.5 with a slight dependence on the repulsive pairwise elastic forces.
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Affiliation(s)
- Tianfei Liu
- McKetta Department of Chemical Engineering and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712, USA.
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20
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Abstract
Rheology of a dilute cohesive granular gas is theoretically and numerically studied. The flow curve between the shear viscosity and the shear rate is derived from the inelastic Boltzmann equation for particles having square-well potentials in a simple shear flow. It is found that (i) the stable uniformly sheared state only exists above a critical shear rate and (ii) the viscosity in the uniformly sheared flow is almost identical to that for uniformly sheared flow of hard core granular particles. Below the critical shear rate, clusters grow with time, in which the viscosity can be approximated by that for the hard-core fluids if we replace the diameter of the particle by the mean diameter of clusters.
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Affiliation(s)
- Satoshi Takada
- Earthquake Research Institute, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.,Department of Physics, Kyoto University, Kitashirakawa Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hisao Hayakawa
- Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawa Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan
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21
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Lin J, Wyart M. Microscopic processes controlling the Herschel-Bulkley exponent. Phys Rev E 2018; 97:012603. [PMID: 29448383 DOI: 10.1103/physreve.97.012603] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Indexed: 06/08/2023]
Abstract
The flow curve of various yield stress materials is singular as the strain rate vanishes and can be characterized by the so-called Herschel-Bulkley exponent n=1/β. A mean-field approximation due to Hebraud and Lequeux (HL) assumes mechanical noise to be Gaussian and leads to β=2 in rather good agreement with observations. Here we prove that the improved mean-field model where the mechanical noise has fat tails instead leads to β=1 with logarithmic correction. This result supports that HL is not a suitable explanation for the value of β, which is instead significantly affected by finite-dimensional effects. From considerations on elastoplastic models and on the limitation of speed at which avalanches of plasticity can propagate, we argue that β=1+1/(d-d_{f}), where d_{f} is the fractal dimension of avalanches and d the spatial dimension. Measurements of d_{f} then supports that β≈2.1 and β≈1.7 in two and three dimensions, respectively. We discuss theoretical arguments leading to approximations of β in finite dimensions.
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Affiliation(s)
- Jie Lin
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Matthieu Wyart
- Institute of Theoretical Physics, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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22
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Jones MA, Ness C. Linking attractive interactions and confinement to the rheological response of suspended particles close to jamming. GRANULAR MATTER 2017; 20:3. [PMID: 31983891 PMCID: PMC6954019 DOI: 10.1007/s10035-017-0770-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Indexed: 06/10/2023]
Abstract
We study the response to simple shear start-up of an overdamped, athermal assembly of particles with tuneable attractive interactions. We focus on volume fractions close to the jamming point, where such systems can become disordered elastoplastic solids. By systematically varying the strength of the particle-particle attraction and the volume fraction, we demonstrate how cohesion and confinement individually contribute to the shear modulus and yield strain of the material. The results provide evidence for the influence of binding agents on the rheology of dense, athermal suspensions and describe a set of handles with which the macroscopic properties of such materials can be engineered.
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Affiliation(s)
- Michael A. Jones
- Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE UK
| | - Christopher Ness
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, CB3 0AS UK
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23
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Kim HS, Mason TG. Advances and challenges in the rheology of concentrated emulsions and nanoemulsions. Adv Colloid Interface Sci 2017; 247:397-412. [PMID: 28821349 DOI: 10.1016/j.cis.2017.07.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 07/02/2017] [Indexed: 11/26/2022]
Abstract
We review advances that have been made in the rheology of concentrated emulsions and nanoemulsions, which can serve as model soft materials that have highly tunable viscoelastic properties at droplet volume fractions near and above the glass transition and jamming point. As revealed by experiments, simulations, and theoretical models, interfacial and positional structures of droplets can depend on the applied flow history and osmotic pressure that an emulsion has experienced, thereby influencing its key rheological properties such as viscoelastic moduli, yield stress and strain, and flow behavior. We emphasize studies of monodisperse droplets, since these have led to breakthroughs in the fundamental understanding of dispersed soft matter. This review also covers the rheological properties of attractive emulsions, which can exhibit a dominant elasticity even at droplet volume fractions far below maximal random jamming of hard spheres.
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24
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Irani E, Chaudhuri P, Heussinger C. Athermal rheology of weakly attractive soft particles. Phys Rev E 2016; 94:052608. [PMID: 27967137 DOI: 10.1103/physreve.94.052608] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Indexed: 06/06/2023]
Abstract
We study the rheology of a soft particulate system where the interparticle interactions are weakly attractive. Using extensive molecular dynamics simulations, we scan across a wide range of packing fractions (ϕ), attraction strengths (u), and imposed shear rates (γ[over ̇]). In striking contrast to repulsive systems, we find that at small shear rates generically a fragile isostatic solid is formed even if we go to ϕ≪ϕ_{J}. Further, with increasing shear rates, even at these low ϕ, nonmonotonic flow curves occur which lead to the formation of persistent shear bands in large enough systems. By tuning the damping parameter, we also show that inertia plays an important role in this process. Furthermore, we observe enhanced particle dynamics in the attraction-dominated regime as well as a pronounced anisotropy of velocity and diffusion constant, which we take as precursors to the formation of shear bands. At low enough ϕ, we also observe structural changes via the interplay of low shear rates and attraction with the formation of microclusters and voids. Finally, we characterize the properties of the emergent shear bands, and thereby, we find surprisingly small mobility of these bands, leading to prohibitively long time scales and extensive history effects in ramping experiments.
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Affiliation(s)
- Ehsan Irani
- Institute for Theoretical Physics, Georg-August University of Göttingen, Friedrich-Hund Platz 1, 37077 Göttingen, Germany
| | - Pinaki Chaudhuri
- Institute of Mathematical Sciences, Taramani, Chennai 600 113, Tamil Nadu, India
| | - Claus Heussinger
- Institute for Theoretical Physics, Georg-August University of Göttingen, Friedrich-Hund Platz 1, 37077 Göttingen, Germany
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25
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Menon K, Govindarajan R, Tewari S. Attraction-induced jamming in the flow of foam through a channel. SOFT MATTER 2016; 12:7772-7781. [PMID: 27526347 DOI: 10.1039/c6sm01719c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We study the flow of a pressure-driven foam through a straight channel using numerical simulations, and examine the effects of a tuneable attractive potential between bubbles. We show that the effect of an attractive potential is to introduce a regime of jamming and stick-slip flow in a channel, and report on the behaviour resulting from varying the strength of the attraction. We find that there is a force threshold below which the flow jams, and upon further increasing the driving force, a crossover from intermittent (stick-slip) to smooth flow is observed. This threshold force below which the foam jams increases linearly with the strength of the attractive potential. By examining the spectra of energy fluctuations, we show that stick-slip flow is characterized by low frequency rearrangements and strongly local behaviour, whereas steady flow shows a broad spectrum of energy drop events and collective behaviour. Our work suggests that the stick-slip and the jamming regimes occur due to the increased stabilization of contact networks by the attractive potential - as the strength of attraction is increased, bubbles are increasingly trapped within networks, and there is a decrease in the number of contact changes.
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Affiliation(s)
- Karthik Menon
- TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Narsingi, Hyderabad - 500075, India
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26
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Shrivastav GP, Chaudhuri P, Horbach J. Yielding of glass under shear: A directed percolation transition precedes shear-band formation. Phys Rev E 2016; 94:042605. [PMID: 27841596 DOI: 10.1103/physreve.94.042605] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Indexed: 06/06/2023]
Abstract
Under external mechanical loading, glassy materials, ranging from soft matter systems to metallic alloys, often respond via formation of inhomogeneous flow patterns, during yielding. These inhomogeneities can be precursors to catastrophic failure, implying that a better understanding of their underlying mechanisms could lead to the design of smarter materials. Here, extensive molecular dynamics simulations are used to reveal the emergence of heterogeneous dynamics in a binary Lennard-Jones glass, subjected to a constant strain rate. At a critical strain, this system exhibits for all considered strain rates a transition towards the formation of a percolating cluster of mobile regions. We give evidence that this transition belongs to the universality class of directed percolation. Only at low shear rates, the percolating cluster subsequently evolves into a transient (but long-lived) shear band with a diffusive growth of its width. Finally, the steady state with a homogeneous flow pattern is reached. In the steady state, percolation transitions also do occur constantly, albeit over smaller strain intervals, to maintain the stationary plastic flow in the system.
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Affiliation(s)
- Gaurav Prakash Shrivastav
- Institut für Theoretische Physik II, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Pinaki Chaudhuri
- The Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600 113, India
| | - Jürgen Horbach
- Institut für Theoretische Physik II, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
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27
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Benzi R, Sbragaglia M, Bernaschi M, Succi S, Toschi F. Cooperativity flows and shear-bandings: a statistical field theory approach. SOFT MATTER 2016; 12:514-530. [PMID: 26486875 DOI: 10.1039/c5sm01862e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Cooperativity effects have been proposed to explain the non-local rheology in the dynamics of soft jammed systems. Based on the analysis of the free-energy model proposed by L. Bocquet, A. Colin and A. Ajdari, Phys. Rev. Lett., 2009, 103, 036001, we show that cooperativity effects resulting from the non-local nature of the fluidity (inverse viscosity) are intimately related to the emergence of shear-banding configurations. This connection materializes through the onset of inhomogeneous compact solutions (compactons), wherein the fluidity is confined to finite-support subregions of the flow and strictly zero elsewhere. The compacton coexistence with regions of zero fluidity ("non-flowing vacuum") is shown to be stabilized by the presence of mechanical noise, which ultimately shapes up the equilibrium distribution of the fluidity field, the latter acting as an order parameter for the flow-noflow transitions occurring in the material.
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Affiliation(s)
- R Benzi
- Department of Physics and INFN, University of "Tor Vergata", Via della Ricerca Scientifica 1, 00133 Rome, Italy.
| | - M Sbragaglia
- Department of Physics and INFN, University of "Tor Vergata", Via della Ricerca Scientifica 1, 00133 Rome, Italy.
| | - M Bernaschi
- Istituto per le Applicazioni del Calcolo CNR, Via dei Taurini 19, 00185 Rome, Italy
| | - S Succi
- Istituto per le Applicazioni del Calcolo CNR, Via dei Taurini 19, 00185 Rome, Italy
| | - F Toschi
- Istituto per le Applicazioni del Calcolo CNR, Via dei Taurini 19, 00185 Rome, Italy and Department of Physics and Department of Mathematics and Computer Science and J. M. Burgerscentrum, Eindhoven University of Technology, 5600 MB, Eindhoven, Netherlands
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28
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Rahbari SHE, Brinkmann M, Vollmer J. Arrest stress of uniformly sheared wet granular matter. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 91:062201. [PMID: 26172699 DOI: 10.1103/physreve.91.062201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Indexed: 06/04/2023]
Abstract
We conduct extensive independent numerical experiments considering frictionless disks without internal degrees of freedom (rotation, etc.) in two dimensions. We report here that for a large range of the packing fractions below random-close packing, all components of the stress tensor of wet granular materials remain finite in the limit of zero shear rate. This is direct evidence for a fluid-to-solid arrest transition. The offset value of the shear stress characterizes plastic deformation of the arrested state which corresponds to dynamic yield stress of the system. Based on an analytical line of argument, we propose that the mean number of capillary bridges per particle, ν, follows a nontrivial dependence on the packing fraction, ϕ, and the capillary energy, ɛ. Most noticeably, we show that ν is a generic and universal quantity which does not depend on the driving protocol. Using this universal quantity, we calculate the arrest stress, σ(a), analytically based on a balance of the energy injection rate due to the external force driving the flow and the dissipation rate accounting for the rupture of capillary bridges. The resulting prediction of σ(a) is a nonlinear function of the packing fraction, ϕ, and the capillary energy, ɛ. This formula provides an excellent, parameter-free prediction of the numerical data. Corrections to the theory for small and large packing fractions are connected to the emergence of shear bands and of contributions to the stress from repulsive particle interactions, respectively.
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Affiliation(s)
- S H Ebrahimnazhad Rahbari
- Department of Physics, Plasma and Condensed Matter Computational Laboratory, Faculty of Sciences, Azarbaijan Shahid Madani University, 51745-406 Tabriz, Iran
| | - M Brinkmann
- Max-Planck-Institut für Dynamik und Selbstorganisation (MPI DS), 37077 Göttingen, Germany and Experimental Physics, Saarland University, 66123 Saarbrücken, Germany
| | - J Vollmer
- Max-Planck-Institut für Dynamik und Selbstorganisation (MPI DS), 37077 Göttingen, Germany and Fakultät für Physik, Universität Göttingen, 37077 Göttingen, Germany
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29
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Horn T, Löwen H. How does a thermal binary crystal break under shear? J Chem Phys 2014; 141:224505. [DOI: 10.1063/1.4903274] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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30
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Lin J, Lerner E, Rosso A, Wyart M. Scaling description of the yielding transition in soft amorphous solids at zero temperature. Proc Natl Acad Sci U S A 2014; 111:14382-7. [PMID: 25246567 PMCID: PMC4210034 DOI: 10.1073/pnas.1406391111] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Yield stress materials flow if a sufficiently large shear stress is applied. Although such materials are ubiquitous and relevant for industry, there is no accepted microscopic description of how they yield, even in the simplest situations in which temperature is negligible and in which flow inhomogeneities such as shear bands or fractures are absent. Here we propose a scaling description of the yielding transition in amorphous solids made of soft particles at zero temperature. Our description makes a connection between the Herschel-Bulkley exponent characterizing the singularity of the flow curve near the yield stress Σc, the extension and duration of the avalanches of plasticity observed at threshold, and the density P(x) of soft spots, or shear transformation zones, as a function of the stress increment x beyond which they yield. We argue that the critical exponents of the yielding transition may be expressed in terms of three independent exponents, θ, df, and z, characterizing, respectively, the density of soft spots, the fractal dimension of the avalanches, and their duration. Our description shares some similarity with the depinning transition that occurs when an elastic manifold is driven through a random potential, but also presents some striking differences. We test our arguments in an elasto-plastic model, an automaton model similar to those used in depinning, but with a different interaction kernel, and find satisfying agreement with our predictions in both two and three dimensions.
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Affiliation(s)
- Jie Lin
- Center for Soft Matter Research, Department of Physics, New York University, New York, NY 10003; and
| | - Edan Lerner
- Center for Soft Matter Research, Department of Physics, New York University, New York, NY 10003; and
| | - Alberto Rosso
- Laboratoire de Physique Théorique et Modèles Statistiques (Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8626), Université de Paris-Sud, 91405 Orsay Cedex, France
| | - Matthieu Wyart
- Center for Soft Matter Research, Department of Physics, New York University, New York, NY 10003; and
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31
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Fielding SM. Shear banding in soft glassy materials. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2014; 77:102601. [PMID: 25303030 DOI: 10.1088/0034-4885/77/10/102601] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Many soft materials, including microgels, dense colloidal emulsions, star polymers, dense packings of multilamellar vesicles, and textured morphologies of liquid crystals, share the basic 'glassy' features of structural disorder and metastability. These in turn give rise to several notable features in the low frequency shear rheology (deformation and flow properties) of these materials: in particular, the existence of a yield stress below which the material behaves like a solid, and above which it flows like a liquid. In the last decade, intense experimental activity has also revealed that these materials often display a phenomenon known as shear banding, in which the flow profile across the shear cell exhibits macroscopic bands of different viscosity. Two distinct classes of yield stress fluid have been identified: those in which the shear bands apparently persist permanently (for as long as the flow remains applied), and those in which banding arises only transiently during a process in which a steady flowing state is established out of an initial rest state (for example, in a shear startup or step stress experiment). Despite being technically transient, such bands may in practice persist for a very long time and so be mistaken for the true steady state response of the material in experimental practice. After surveying the motivating experimental data, we describe recent progress in addressing it theoretically, using the soft glassy rheology model and a simple fluidity model. We also briefly place these theoretical approaches in the context of others in the literature, including elasto-plastic models, shear transformation zone theories, and molecular dynamics simulations. We discuss finally some challenges that remain open to theory and experiment alike.
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Affiliation(s)
- S M Fielding
- Department of Physics, Durham University, Science Laboratories, South Road, Durham DH1 3LE, UK
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Singh A, Magnanimo V, Saitoh K, Luding S. Effect of cohesion on shear banding in quasistatic granular materials. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:022202. [PMID: 25215728 DOI: 10.1103/physreve.90.022202] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Indexed: 06/03/2023]
Abstract
Cohesive powders have widely different bulk behavior due to their peculiar interactions. We use discrete element simulations to investigate the effect of contact cohesion on the steady state flow of dense powders in a slowly sheared split-bottom Couette cell, which imposes a wide stable shear band. The intensity of cohesive forces can be quantified by the granular Bond number (Bo), namely the ratio between maximum attractive force and average force due to external compression. We find that the shear banding phenomenon is almost independent of cohesion for Bond numbers Bo<1, however for Bo≥1 cohesive forces start to play an important role, as both width and center position of the band increase. Inside the shear band, the mean normal contact force is independent of cohesion and depends only on the confining stress. In contrast, when the behavior is analyzed focusing on the eigendirections of the local strain rate tensor, a dependence on cohesion shows up. Forces carried by contacts along the compressive and tensile directions are symmetric about the mean force (larger and smaller respectively), while the force along the third, neutral direction follows the mean force. This anisotropy of the force network increases with cohesion, just like the heterogeneity in all (compressive, tensile and neutral) directions.
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Affiliation(s)
- Abhinendra Singh
- Multi Scale Mechanics (MSM), Faculty of Engineering Technology, MESA+, University of Twente, P. O. Box 217, 7500 AE Enschede, The Netherlands
| | - Vanessa Magnanimo
- Multi Scale Mechanics (MSM), Faculty of Engineering Technology, MESA+, University of Twente, P. O. Box 217, 7500 AE Enschede, The Netherlands
| | - Kuniyasu Saitoh
- Multi Scale Mechanics (MSM), Faculty of Engineering Technology, MESA+, University of Twente, P. O. Box 217, 7500 AE Enschede, The Netherlands
| | - Stefan Luding
- Multi Scale Mechanics (MSM), Faculty of Engineering Technology, MESA+, University of Twente, P. O. Box 217, 7500 AE Enschede, The Netherlands
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33
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Gross M, Krüger T, Varnik F. Rheology of dense suspensions of elastic capsules: normal stresses, yield stress, jamming and confinement effects. SOFT MATTER 2014; 10:4360-72. [PMID: 24796957 DOI: 10.1039/c4sm00081a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We study the shearing rheology of dense suspensions of elastic capsules, taking aggregation-free red blood cells as a physiologically relevant example. Particles are non-Brownian and interact only via hydrodynamics and short-range repulsive forces. An analysis of the different stress mechanisms in the suspension shows that the viscosity is governed by the shear elasticity of the capsules, whereas the repulsive forces are subdominant. Evidence for a dynamic yield stress above a critical volume fraction is provided and related to the elastic properties of the capsules. The shear stress is found to follow a critical jamming scenario and is rather insensitive to the tumbling-to-tank-treading transition. The particle pressure and normal stress differences display some sensitivity to the dynamical state of the cells and exhibit a characteristic scaling, following the behavior of a single particle, in the tank-treading regime. The behavior of the viscosity in the fluid phase is rationalized in terms of effective medium models. Furthermore, the role of confinement effects, which increase the overall magnitude and enhance the shear-thinning of the viscosity, is discussed.
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Affiliation(s)
- Markus Gross
- Interdisciplinary Centre for Advanced Materials Simulation (ICAMS), Ruhr-Universität Bochum, Universitätsstr. 150, 44780 Bochum, Germany.
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34
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Irani E, Chaudhuri P, Heussinger C. Impact of attractive interactions on the rheology of dense athermal particles. PHYSICAL REVIEW LETTERS 2014; 112:188303. [PMID: 24856729 DOI: 10.1103/physrevlett.112.188303] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Indexed: 06/03/2023]
Abstract
Using numerical simulations, the rheological response of an athermal assembly of soft particles with tunable attractive interactions is studied in the vicinity of jamming. At small attractions, a fragile solid develops and a finite yield stress is measured. Moreover, the measured flow curves have unstable regimes, which lead to persistent shear banding. These features are rationalized by establishing a link between the rheology and the interparticle connectivity, which also provides a minimal model to describe the flow curves.
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Affiliation(s)
- Ehsan Irani
- Institute for Theoretical Physics, Georg-August University of Göttingen, Friedrich-Hund Platz 1, 37077 Göttingen, Germany
| | - Pinaki Chaudhuri
- Institut für Theoretische Physik II, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Claus Heussinger
- Institute for Theoretical Physics, Georg-August University of Göttingen, Friedrich-Hund Platz 1, 37077 Göttingen, Germany
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35
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Grenard V, Divoux T, Taberlet N, Manneville S. Timescales in creep and yielding of attractive gels. SOFT MATTER 2014; 10:1555-1571. [PMID: 24651869 DOI: 10.1039/c3sm52548a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The stress-induced yielding scenario of colloidal gels is investigated under rough boundary conditions by means of rheometry coupled with local velocity measurements. Under an applied shear stress σ, the fluidization of gels made of attractive carbon black particles dispersed in a mineral oil is shown to involve a previously unreported shear rate response γ dot above(t) characterized by two well-defined and separated timescales τc and τf. First γ dot above decreases as a weak power law strongly reminiscent of the primary creep observed in numerous crystalline and amorphous solids, coined the "Andrade creep". We show that the bulk deformation remains homogeneous at the micron scale, which demonstrates that whether plastic events take place or whether any shear transformation zone exists, such phenomena occur at a smaller scale. As a key result of this paper, the duration τc of this creep regime decreases as a power law of the viscous stress, defined as the difference between the applied stress and the yield stress σc, i.e. τc ∼ (σ - σc)(-β), with β = 2-3 depending on the gel concentration. The end of this first regime is marked by a jump of the shear rate by several orders of magnitude, while the gel slowly slides as a solid block experiencing strong wall slip at both walls, despite rough boundary conditions. Finally, a second sudden increase of the shear rate is concomitant with the full fluidization of the material which ends up being homogeneously sheared. The corresponding fluidization time τf robustly follows an exponential decay with the applied shear stress, i.e. τf = τ0 exp(-σ/σ0), as already reported for smooth boundary conditions. Varying the gel concentration C in a systematic fashion shows that the parameter σ0 and the yield stress σc exhibit similar power-law dependences with C. Finally, we highlight a few features that are common to attractive colloidal gels and to solid materials by discussing our results in the framework of theoretical approaches of solid rupture (kinetic, fiber bundle, and transient network models).
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Affiliation(s)
- Vincent Grenard
- Université de Lyon, Laboratoire de Physique, École Normale Supérieure de Lyon, CNRS UMR 5672 - 46 allée d'Italie, 69364 Lyon cedex 07, France.
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36
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Gattinoni C, Heyes DM, Lorenz CD, Dini D. Traction and nonequilibrium phase behavior of confined sheared liquids at high pressure. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:052406. [PMID: 24329278 DOI: 10.1103/physreve.88.052406] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Indexed: 06/03/2023]
Abstract
Nonequilibrium molecular dynamics simulations of confined model liquids under pressure and sheared by the relative sliding of the boundary walls have been carried out. The relationship between the time-dependent traction coefficient, μ(t), and the state of internal structure of the film is followed from commencement of shear for various control parameters, such as applied load, global shear rate, and solid-liquid atom interaction parameters. Phase diagrams, velocity and temperature profiles, and traction coefficient diagrams are analyzed for pure Lennard-Jones (LJ) liquids and a binary LJ mixture. A single component LJ liquid is found to form semicrystalline arrangements with high-traction coefficients, and stick-slip behavior is observed for high pressures and low-shear velocities, which is shown to involve periodic deformation and stress release of the wall atoms and slip in the solid-liquid boundary region. A binary mixture, which discourages crystallization, gives a more classical tribological response with the larger atoms preferentially adsorbing commensurate with the wall. The results obtained are analyzed in the context of tribology: the binary mixture behaves like a typical lubricant, whereas the monatomic system behaves like a traction fluid. It is discussed how this type of simulation can give insights on the tribological behavior of realistic systems.
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Affiliation(s)
- Chiara Gattinoni
- Department of Mechanical Engineering, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, United Kingdom
| | - David M Heyes
- Department of Mechanical Engineering, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, United Kingdom
| | - Christian D Lorenz
- Department of Physics, King's College London, Strand, London WC2R 2LS, United Kingdom
| | - Daniele Dini
- Department of Mechanical Engineering, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, United Kingdom
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37
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Chaudhuri P, Horbach J. Onset of flow in a confined colloidal glass under an imposed shear stress. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:040301. [PMID: 24229095 DOI: 10.1103/physreve.88.040301] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2012] [Indexed: 06/02/2023]
Abstract
A confined colloidal glass, under the imposition of a uniform shear stress, is investigated using numerical simulations. Both at macro- and microscales, the consequent dynamics during the onset of flow is studied. When the imposed stress is gradually decreased, the time scale for the onset of steady flow diverges, associated with long-lived spatial heterogeneities. Near this yield-stress regime, persistent creep in the form of shear-banded structures is observed.
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Affiliation(s)
- Pinaki Chaudhuri
- Institut für Theoretische Physik II, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany and Johannes-Gutenberg-Universität Mainz, Institut für Physik, WA 331, 55099 Mainz, Germany
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38
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Le Merrer M, Cohen-Addad S, Höhler R. Duration of bubble rearrangements in a coarsening foam probed by time-resolved diffusing-wave spectroscopy: impact of interfacial rigidity. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:022303. [PMID: 24032829 DOI: 10.1103/physreve.88.022303] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Indexed: 06/02/2023]
Abstract
In aqueous foams, the diffusive gas transfer among neighboring bubbles drives a coarsening process which is accompanied by intermittent rearrangements of the structure. Using time-resolved diffusing-wave spectroscopy, we probe the dynamics of these events as a function of the rigidity of the gas-liquid interfaces, liquid viscosity, bubble size, and confinement pressure. We present in detail two independent techniques for analyzing the light scattering data, from which we extract the rearrangement duration. Our results show that interfacial rheology has a major impact on this duration. In the case of low interfacial rigidity, the rearrangements strongly slow down as the pressure is decreased close to the value zero where the bubble packing unjams. In contrast, if the interfaces are rigid, rearrangement durations are independent of the confinement pressure in the same investigated range. Using scaling arguments, we discuss dissipation mechanisms that may explain the observed dependency of the rearrangement dynamics on foam structure, pressure, and physicochemical solution properties.
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Affiliation(s)
- Marie Le Merrer
- Université Paris 6, UMR 7588 CNRS-UPMC, INSP, 4 place Jussieu, 75252 Paris Cedex 05, France
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39
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Fiocco D, Foffi G, Sastry S. Oscillatory athermal quasistatic deformation of a model glass. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:020301. [PMID: 24032763 DOI: 10.1103/physreve.88.020301] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 07/12/2013] [Indexed: 06/02/2023]
Abstract
We report computer simulations of oscillatory athermal quasistatic shear deformation of dense amorphous samples of a three-dimensional model glass former. A dynamical transition is observed as the amplitude of the deformation is varied: For large values of the amplitude the system exhibits diffusive behavior and loss of memory of the initial conditions, whereas localization is observed for small amplitudes. Our results suggest that the same kind of transition found in driven colloidal systems is present in the case of amorphous solids (e.g., metallic glasses). The onset of the transition is shown to be related to the onset of energy dissipation. Shear banding is observed for large system sizes, without, however, affecting qualitative aspects of the transition.
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Affiliation(s)
- Davide Fiocco
- Institute of Theoretical Physics, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
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40
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Regev I, Reichhardt C. Rheology and shear band suppression in particle and chain mixtures. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 87:020201. [PMID: 23496443 DOI: 10.1103/physreve.87.020201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Indexed: 06/01/2023]
Abstract
Using numerical simulations we consider an amorphous particle mixture which exhibits shear localization, and find that the addition of even a small fraction of chains strongly enhances the material strength, creating pronounced overshoot features in the stress-strain curves. The strengthening occurs in the case where the chains are initially perpendicular to the shear direction, leading to a suppression of the shear band. This also leads to stiffening effects that are typical of polymeric systems. For large strain, the chains migrate to the region where a shear band forms, resulting in a stress drop. For chains larger than the linear system size we find oscillatory behavior, which does not resemble polymeric systems since the second stress peak is larger than the first. Our results are also useful for providing insights into methods of controlling and strengthening granular materials against failure.
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Affiliation(s)
- I Regev
- Center for Nonlinear Studies and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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