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1. Stress Corrosion Cracking in Amorphous Phase Separated Oxide Glasses: A Holistic Review of Their Structures, Physical, Mechanical and Fracture Properties

Author

F. Celarie, Stéphane Gossé, Patrick Houizot, Daniel Bonamy, Cindy L. Rountree, Weiying Feng, Paul C. M. Fossati, Université Paris-Saclay, CEA- Saclay (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UNIV-RENNES), Service de la Corrosion et du Comportement des Matériaux dans leur Environnement (SCCME), Département de Physico-Chimie (DPC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, DIM-MAP AFM4aStory, ANR-17-CE08-0004,ToughGlasses,Amélioration de la réponse des verres d'oxydes à la Corrosion Sous Contrainte (CSC)(2017), Systèmes Physiques Hors-équilibre, hYdrodynamique, éNergie et compleXes (SPHYNX), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Spinodal decomposition, Oxide, 02 engineering and technology, TP1-1185, mechanical properties, 01 natural sciences, physical properties, chemistry.chemical_compound, Metastability, 0103 physical sciences, [SPI.MECA.MEMA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanics of materials [physics.class-ph], Composite material, Stress corrosion cracking, sodium borosilicate glasses, ComputingMilieux_MISCELLANEOUS, 010302 applied physics, [PHYS]Physics [physics], Borosilicate glass, miscibility gap, Chemical technology, dynamic fracture, General Medicine, 021001 nanoscience & nanotechnology, Microstructure, stress corrosion cracking, chemistry, amorphous phase separation, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Fracture (geology), 0210 nano-technology, Ternary operation
Abstract

International audience; Stress corrosion cracking is a well-known phenomenon in oxide glasses. However, how amorphous phase separation (APS) alters stress corrosion cracking, and the overall mechanical response of an oxide glass is less known in literature. APS is a dominant feature concerning many multicomponent systems, particularly the ternary sodium borosilicate (SBN) glass systems. Its three constituent oxides have significant industrial relevance, as they are the principal components of many industrial oxide glasses. Simulations and experimental studies demonstrate the existence of a two-phase metastable miscibility gap. Furthermore, theory suggests the possibility of three-phase APS in these oxide glasses. Literature already details the mechanisms of phase separation and characterizes SBN microstructures. Realizing that glasses are structurally sensitive materials opens a number of other questions concerning how the mesoscopic APS affects the continuum behavior of glasses, including dynamic fracture and stress corrosion cracking. This paper reviews current literature and provides a synthetic viewpoint on how APS structures of oxide glasses alter physical, mechanical, dynamic fracture, and stress corrosion cracking properties

Published
2021
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2. Roughness of oxide glass subcritical fracture surfaces

Author

Frederic Lechenault, Matthieu George, Matteo Ciccotti, Cindy L. Rountree, Cédric Ottina, Gaël Pallares, Elisabeth Bouchaud, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Statistique de l'ENS (LPS), Université Paris Diderot - Paris 7 (UPD7)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Gulliver (UMR 7083), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique de l'ENS Lyon (Phys-ENS), École normale supérieure - Lyon (ENS Lyon)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Sciences et Ingénierie de la Matière Molle (SIMM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Sciences et Ingénierie de la Matière Molle (UMR 7615) (SIMM), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, FOS: Physical sciences, 02 engineering and technology, Surface finish, Condensed Matter - Soft Condensed Matter, 01 natural sciences, Root mean square, Crack closure, 0103 physical sciences, Materials Chemistry, Surface roughness, Forensic engineering, surface, Coupling (piping), Composite material, 010306 general physics, Stress intensity factor, roughness, glass, Fracture mechanics, 021001 nanoscience & nanotechnology, fracture, Ceramics and Composites, Fracture (geology), Soft Condensed Matter (cond-mat.soft), 0210 nano-technology, [PHYS.COND.CM-SCM]Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft]
Abstract

International audience; An original setup combining a very stable loading stage, an atomic force microscope and an environmental chamber, allows to obtain very stable sub-critical fracture propagation in oxide glasses under controlled environment, and subsequently to finely characterize the nanometric roughness properties of the crack surfaces. The analysis of the surface roughness is conducted both in terms of the classical root mean square roughness to compare with the literature, and in terms of more physically adequate indicators related to the self-affine nature of the fracture surfaces. Due to the comparable nanometric scale of the surface roughness, the AFM tip size and the instrumental noise, a special care is devoted to the statistical evaluation of the metrologic properties. The 2 roughness amplitude of several oxide glasses was shown to decrease as a function of the stress intensity factor, to be quite insensitive to the relative humidity and to increase with the degree of heterogeneity of the glass. The results are discussed in terms of several modeling arguments concerning the coupling between crack propagation, material's heterogeneity, crack tip plastic deformation and water diffusion at the crack tip. A synthetic new model is presented combining the predictions of a model by Wiederhorn et al. [1] on the effect of the material's heterogeneity on the crack tip stresses with the self-affine nature of the fracture surfaces.

Published
2017
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3. Highly porous layers of silica nano-spheres sintered by drying: Scaling up of the elastic properties from the beads to the macroscopic mechanical properties

Author

Cindy L. Rountree, Daniel Bonamy, Arnaud Lesaine, Georges Gauthier, Véronique Lazarus, Fluides, automatique, systèmes thermiques (FAST), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Systèmes Physiques Hors-équilibre, hYdrodynamique, éNergie et compleXes (SPHYNX), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la mécanique et Applications industrielles (IMSIA - UMR 9219), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), ANR-10-LABX-0032,LaSIPS,LABORATORY FOR SYSTEMS AND ENGINEERING OF PARIS SACLAY(2010), ANR-10-LABX-0039,PALM,Physics: Atoms, Light, Matter(2010), ANR-11-IDEX-0003,IPS,Idex Paris-Saclay(2011), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-EDF R&D (EDF R&D)

Subjects
Materials science, drying of colloidal dispersions, FOS: Physical sciences, PACS numbers: 82.70 Dd, 62.20.de, 81.16.Dn, 02 engineering and technology, Physics - Classical Physics, Condensed Matter - Soft Condensed Matter, mechanical properties, 01 natural sciences, Homogenization (chemistry), [PHYS.MECA.MEMA]Physics [physics]/Mechanics [physics]/Mechanics of materials [physics.class-ph], 0103 physical sciences, Composite material, 010306 general physics, Porosity, Anisotropy, [PHYS]Physics [physics], Continuum mechanics, Multi-scale homogenization approaches, linear elasticity, Classical Physics (physics.class-ph), Fracture mechanics, General Chemistry, particles sintering, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Soft Condensed Matter (cond-mat.soft), 0210 nano-technology, Porous medium, Contact area, Rule of mixtures, [PHYS.COND.CM-SCM]Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft], highly interconnected porosity
Abstract

International audience; Layers obtained by drying a colloidal dispersion of silica spheres are found to be a good benchmark to test the elastic behaviour of porous media, in the challenging case of high porosities and nano-sized microstructures. Classically used for these systems, Kendall's approach explicitly considers the effect of surface adhesive forces onto the contact area between the particles. This approach provides the Young's modulus using a single adjustable parameter (the adhesion energy) but provides no further information on the tensorial nature and possible anisotropy of elasticity. On the other hand, homogenization approaches (e.g. rule of mixtures, and Eshelby, Mori-Tanaka and self-consistent schemes), based on continuum mechanics and asymptotic analysis, provide the stiffness tensor from the knowledge of the porosity and the elastic constants of the beads. Herein, the self-consistent scheme accurately predicts both bulk and shear moduli, with no adjustable parameter, provided the porosity is less than 35%, for layers composed of particles as small as 15 nm in diameter. Conversely, Kendall's approach is found to predict the Young's modulus over the full porosity range. Moreover, the adhesion energy in Kendall's model has to be adjusted to a value of the order of the fracture energy of the particle material. This suggests that sintering during drying leads to the formation of covalent siloxane bonds between the particles.

Published
2018
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4. Influence of Electronic Irradiation on Failure and Hardness Properties of Pure Silica Glasses

Author

Marina Barlet, Bruno Boizot, Cindy L. Rountree, J-M. Delaye, Richard Caraballo, Daniel Bonamy, M. Gennisson, Service de Physique et de Chimie des Surfaces et Interfaces (SPCSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Service d'Etudes du Comportement des Matériaux de Conditionnement (SECM), Laboratoire des Matériaux et Procédés Actifs (LMPA), Département de recherche sur les technologies pour l'enrichissement, le démantèlement et les déchets (DE2D), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire des Solides Irradiés (LSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Département de recherche sur les Procédés et Matériaux pour les Environnements complexes (DPME), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010302 applied physics, Oxide minerals, Materials science, Fracture mechanics, [CHIM.MATE]Chemical Sciences/Material chemistry, 02 engineering and technology, General Medicine, Crystal structure, 021001 nanoscience & nanotechnology, Microstructure, 01 natural sciences, Crystallographic defect, Indentation, 0103 physical sciences, Vickers hardness test, Irradiation, Composite material, 0210 nano-technology
Abstract

International audience; This paper’s focus is the failure and hardness properties of pure amorphous silica (Corning 7980) after β-irradiation at differentdoses (0-2 GGy). Crack propagation takes place in the SCC regime (10−7-10−10 m.s−1) and Vickers indentation techniques probethe hardness properties of the samples. Irradiation is found to create point defects which mainly include E’ centers, Non-BridgingOxygen Hole Centers and Peroxy Radicals. β-irradiation herein invokes minor changes in the structure. A small effect of β-irradiation on SCC and hardness variations cannot be eliminated, despite minute variations in the SCC and the hardness properties.

Published
2014
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5. Role of evaporation rate on the particle organization and crack patterns obtained by drying a colloidal layer

Author

Daniel Bonamy, Georges Gauthier, Véronique Lazarus, Keyvan Piroird, Cindy L. Rountree, Arnaud Lesaine, Fluides, automatique, systèmes thermiques (FAST), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Systèmes Physiques Hors-équilibre, hYdrodynamique, éNergie et compleXes (SPHYNX), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and Triangle de la Physique (RTRA), Ile-de-France (C'Nano and ISC-PIF) and Investissements d'Avenir of LabEx PALM (ANR-10-LABX-0039-PALM) and LabEx LaSIPS (ANR-10-LABX-0040-LaSIPS)

Subjects
Materials science, Solid structure, Cracks, Porous film, Evaporation rate, education, General Physics and Astronomy, FOS: Physical sciences, 02 engineering and technology, Condensed Matter - Soft Condensed Matter, 010402 general chemistry, 01 natural sciences, Colloid, Surface analysis via Atomic force microscopy (AFM), Colloids, Composite material, [PHYS.COND.CM-SM]Physics [physics]/Condensed Matter [cond-mat]/Statistical Mechanics [cond-mat.stat-mech], Nanoscopic scale, Condensed Matter - Statistical Mechanics, Statistical Mechanics (cond-mat.stat-mech), Self-assembly, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Particle, Soft Condensed Matter (cond-mat.soft), 0210 nano-technology, Layer (electronics), [PHYS.COND.CM-SCM]Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft]
Abstract

International audience; – A scientific hurdle in manufacturing solid films by drying colloidal layers is preventing them from fracturing. This paper examines how the drying rate of colloidal liquids influences the particle packing at the nanoscale in correlation with the crack patterns observed at the macroscale. Increasing the drying rate results in more ordered, denser solid structures, and the dried samples have more cracks.Yet, introducing a holding period (at a prescribed point) during the drying protocol results in a more disordered solid structure with significantly less cracks. To interpret these observations, this paper conjectures that a longer drying protocol favors the formation of aggregates. It is further argued that the number and size of the aggregates increase as the drying rate decreases. This results in the formation of a more disordered, porous film from the viewpoint of the particle packing, and a more resistant film, i.e. less cracks, from the macroscale viewpoint.

Published
2016
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6. Nanoscale damage during fracture in silica glass

Author

Cindy L. Rountree, Krishnaswa Ravi-Chandar, S. Prades, C. Guillot, Elisabeth Bouchaud, Davy Dalmas, Laurent Ponson, and Daniel Bonamy

Subjects
Coalescence (physics), Nanostructure, Materials science, Metallurgy, Computational Mechanics, Nucleation, Fracture mechanics, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Corrosion, Mechanics of Materials, Corrosion fatigue, Modeling and Simulation, Cavitation, 0103 physical sciences, Composite material, 010306 general physics, 0210 nano-technology, Nanoscopic scale
Abstract

We report here atomic force microscopy experiments designed to uncover the nature of failure mechanisms occuring within the process zone at the tip of a crack propagating into a silica glass specimen under stress corrosion. The crack propagates through the growth and coalescence of nanoscale damage spots. This cavitation process is shown to be the key mechanism responsible for damage spreading within the process zone. The possible origin of the nucleation of cavities, as well as the implications on the selection of both the cavity size at coalescence and the process zone extension are finally discussed.

Published
2006
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7. Hardness and toughness of sodium borosilicate glasses via Vickers's indentations

Author

Marina Barlet, Thibault Charpentier, Daniel Bonamy, Tanguy Rouxel, Jean-Marc Delaye, Cindy L. Rountree, Mickael Gennisson, Systèmes Physiques Hors-équilibre, hYdrodynamique, éNergie et compleXes (SPHYNX), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Service de Physique et de Chimie des Surfaces et Interfaces (SPCSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Service d'Etudes du Comportement des Matériaux de Conditionnement (SECM), Laboratoire Structure et Dynamique par Résonance Magnétique (LCF) (LSDRM), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Support by Triangle de la Physique (RTRA grant IMAFMP) and Ile-deFrance(C'Nano and ISC-PIF grant IMAFMP), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Université de Rennes 1 (UR1), and Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics], Toughness, Materials science, Borosilicate glass, Fracture toughness, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, Glass structure, Sodium borosilicate glasses, Residual stress, Hardness, Indentation, Materials Chemistry, Ceramics and Composites, Composite material, Deformation (engineering), Shear flow, Low sodium
Abstract

This study investigates the mechanical response of sodium borosilicate (SBN) glasses as a function of their chemical composition. Vickers's indentation tests provide an estimate of the material hardness ( H V ) and indentation fracture toughness ( K C VIF ) plus the amount of densification/shear flow processes. Sodium content significantly impacts the glass behavior under a sharp indenter. Low sodium glasses maintain high connected networks and low Poisson's ratios ( ν ). This entails significant densification processes during deformation. Conversely, glasses with high sodium content, i.e. large ν , partake in a more depolymerized network favoring deformation by shear flow. As a consequence, indentation patterns differ depending on the processes occurring. Densification processes appear to hinder the formation of half-penny median–radial cracks. Increasing ν favors shear flow and residual stresses enhance the development of half-penny median–radial cracks. Hence, K C VIF decreases linearly with ν .

Published
2015
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8. Roughness of Silica Glass Sub-Critical Fracture Surfaces

Author

Elisabeth Bouchaud, Frederic Lechenault, Matthieu George, Matteo Ciccotti, Gaël Pallares, and Cindy L. Rountree

Subjects
Root mean square, Materials science, Silica glass, Fracture (geology), Sub critical, Surface finish, Composite material, Stress intensity factor
Published
2012
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9. Evidence of deep water penetration in silica during stress corrosion fracture

Author

Jean-Philippe Bouchaud, Laurent Ponson, Cindy L. Rountree, Frederic Lechenault, E. Bouchaud, Fabrice Cousin, Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and California Institute of Technology (CALTECH)

Subjects
Heavy water, [PHYS]Physics [physics], Condensed Matter - Materials Science, Materials science, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, General Physics and Astronomy, Disordered Systems and Neural Networks (cond-mat.dis-nn), Penetration (firestop), Condensed Matter - Disordered Systems and Neural Networks, Reflectivity, Corrosion, Deep water, chemistry.chemical_compound, chemistry, Neutron, Neutron reflectometry, [NLIN]Nonlinear Sciences [physics], Composite material, Penetration depth
Abstract

We measure the thickness of the heavy water layer trapped under the stress corrosion fracture surface of silica using neutron reflectivity experiments. We show that the penetration depth is 65-85 \aa ngstr\"{o}ms, suggesting the presence of a damaged zone of $\approx$ 100 \aa ngstr\"{o}ms extending ahead of the crack tip during its propagation. This estimate of the size of the damaged zone is compatible with other recent results., Comment: 4 pages, 3 figures

Published
2010
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10. Plasticity-induced structural anisotropy of silica glass

Author

Damien Vandembroucq, Stéphane Roux, Mehdi Talamali, Elisabeth Bouchaud, Cindy L. Rountree, Service de Physique et de Chimie des Surfaces et Interfaces (SPCSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Physique et mécanique des milieux hétérogenes (UMR 7636) (PMMH), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Mécanique et Technologie (LMT), École normale supérieure - Cachan (ENS Cachan)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), ANR-05-BLAN-0367,PLASTIGLASS,Modélisation multi-échelles et techniques micro-spectroscopiques pour l'étude de la plasticité des verres(2005), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)

Subjects
Materials science, amorphous, orientational order, General Physics and Astronomy, FOS: Physical sciences, 02 engineering and technology, anisotropy, Plasticity, 01 natural sciences, Molecular dynamics, 0103 physical sciences, Thermal, Tensor, Composite material, 010306 general physics, Anisotropy, glass, 021001 nanoscience & nanotechnology, Microstructure, fabric tensor, Amorphous solid, Condensed Matter - Other Condensed Matter, silica, plasticity, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0210 nano-technology, Ambient pressure, Other Condensed Matter (cond-mat.other)
Abstract

International audience; Amorphous silica density at ambient pressure is known to depend on thermal history (through the quenching rate) but also, at room temperature, on the maximum pressure applied in the past. Here we show that beyond density, a mechanical loading can endow the structure with an orientational order. Molecular dynamics simulations show evidence that amorphous silica develops a permanent anisotropic structure after extended shear plastic flow. This anisotropy which survives for an unstressed specimen is revealed markedly by the fabric tensor computed over the Si-O-Si orientations, albeit the SiO4 tetrahedra microstructure remains mostly unaltered.

Published
2009

11. Dynamics of wing cracks and nanoscale damage in glass

Author

Cheng Zhang, Cindy L. Rountree, Zhen Lu, Rajiv K. Kalia, Ashish Sharma, Aiichiro Nakano, Priya Vashishta, Weiqiang Wang, Elisabeth Bouchaud, Ken-ichi Nomura, University of Southern California (USC), Service de Physique et de Chimie des Surfaces et Interfaces (SPCSI), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
Coalescence (physics), [PHYS]Physics [physics], Wing, Materials science, Fissure, Wing crack, General Physics and Astronomy, Fracture mechanics, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, medicine.anatomical_structure, 0103 physical sciences, medicine, PACS numbers: 62.20.Mk, 31.15.Qg, 62.30.+d, Brittle solids, Dynamic range compression, Composite material, 010306 general physics, 0210 nano-technology, Nanoscopic scale
Abstract

International audience; We investigate initiation, growth, and healing of wing cracks in confined silica glass by molecular dynamics simulations. Under dynamic compression, frictional sliding of precrack surfaces nucleates nanovoids which evolve into nanocrack columns at the precrack tip. Nanocrack columns merge to form a wing crack, which grows via coalescence with nanovoids in the direction of maximum compression. Lateral confinement arrests the growth and partially heals the wing crack. Growth and arrest of the wing crack occur repeatedly, as observed in dynamic compression experiments on brittle solids under lateral confinement.

Published
2005
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12. Experimental investigation of damage and fracture in glassy materials at the nanometre scale

Author

Cindy L. Rountree, Daniel Bonamy, C. Guillot, Davy Dalmas, Laurent Ponson, S. Prades, and Elisabeth Bouchaud

Subjects
Coalescence (physics), Materials science, Mechanical Engineering, Nucleation, Fracture mechanics, Condensed Matter::Disordered Systems and Neural Networks, Industrial and Manufacturing Engineering, Physics::Geophysics, Stress (mechanics), Condensed Matter::Materials Science, Crack closure, Brittleness, Fracture toughness, Mechanics of Materials, Forensic engineering, Nanometre, Composite material, Safety, Risk, Reliability and Quality
Abstract

Slow crack advance is observed in real time via an Atomic Force Microscope in a minimal glass, amorphous Silica, under stress corrosion. Fracture proceeds through the nucleation, growth and coalescence of damage cavities, as recently reported in an aluminosilicate glass. The crack growth velocity as observed at the continuum scale is shown to be dominated by accelerating phases corresponding to the cavity coalescence with the main crack front. The process zone at the crack tip is then determined, and shown to increase with time when both the average crack growth velocity and the mechanical stress are kept constant. Transport of water molecules within the process zone is conjectured to be the dominant mechanism responsible for this time evolution. Migration of alkali Na ions in more complex Silicate glass is finally evidenced at the sub-mocrometric scale by observing through AFM the crack propagation in binary Na2O/SiO2 glasses.

Published
2006
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13. Dynamic fracture mechanisms in nanostructured and amorphous silica glasses million-atom molecular dynamics simulations

Author

Cindy L. Rountree, Priya Vashishta, Aiichiro Nakano, Rajiv K. Kalia, and Laurent Van Brutzel

Subjects
Molecular dynamics, Toughness, Materials science, Fracture toughness, Nanostructure, Cleavage (crystal), Fracture mechanics, Composite material, Amorphous solid, Intergranular fracture
Abstract

Parallel molecular dynamics simulations are performed to investigate dynamic fracture in bulk and nanostructured silica glasses at room temperature and 1000 K. In bulk silica the crack front develops multiple branches and nanoscale pores open up ahead of the crack tip. Pores coalesce and then they merge with the advancing crack-front to cause cleavage fracture. The calculated fracture toughness is in good agreement with experiments. In nanostrucutred silica the crack-front meanders along intercluster boundaries, merging with nanoscale pores in these regions to cause intergranular fracture. The failure strain in nanostructured silica is significantly larger than in the bulk systems.

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