ARNOULD Olivier
Fonction : Maître de Conférences
Organisme : Université Montpellier
Maître de ConférencesDirecteur(trice) de thèse de :
ALKADRI A.,
Autre(s) thème(s) de recherche ou rattachement(s) : - Moyens expérimentaux
olivier.arnould

umontpellier.fr
0467149650
Bureau: 309, Etg: 3, Bât: 2 - Site : Saint-Priest
Administration Locale:- Responsable de formations
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Curriculum Vitae: |
Délégation CNRS à l'IES (Montpellier) 2008-09 Délégation CNRS au l'IRDL (Lorient) 2015-16 Titulaire de la PEDR 2014-2018 |
Activités de Recherche: |
Caractérisation du bois de l'échelle de la paroi cellulaire (AFM) au tissu (DMA, US, RUS) |
Projets de Recherche: |
CNRS PIR "NanoMecPar" ANR "Analogs" Appel d'offre programmes pluridisciplinaires "Modélisation" du CS UM2 ANR "StressInTrees" |
Programme de Recherche/CV: | |
Domaines de Recherche: - Sciences de l'ingénieur/Matériaux
- Sciences de l'ingénieur/Mécanique/Biomécanique
- Sciences de l'ingénieur/Mécanique/Mécanique des matériaux
- Sciences de l'ingénieur/Mécanique/Matériaux et structures en mécanique
- Sciences de l'ingénieur/Mécanique/Vibrations
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Dernieres productions scientifiques :

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On the determination of the elastic constants of carbon fibres by nanoindentation tests 
Auteur(s): Guruprasad T. S., Keryvin Vincent, Charleux Ludovic, Guin Jean-Pierre, Arnould O.
(Article) Publié:
Carbon, vol. 173 p.572-586 (2021)
Ref HAL: hal-03027583_v1
DOI: 10.1016/j.carbon.2020.09.052
Exporter : BibTex | endNote
Résumé: Nano-indentation instrumented tests are carried out at shallow depths on PAN-based and MPP-based carbon fibres. Indentation moduli are obtained by performing the tests at ten different measured orientations with respect to the fibre axis. They are used to identify the elastic constants of the fibres, assuming a transversely isotropic behaviour, by minimising a cost function between measured and estimated values. Inconstancies between the identified in-plane shear and transverse moduli and reported literature values are pointed out, and some drawbacks of the nano-indentation method are highlighted. An improved method taking into account the buckling mechanisms of crystallites at stake during the indentation process, and visible in the hysteretic behaviour of force-penetration nanoindentation curves, is proposed. It allows to identify values of elastic constants that are in accordance with literature values. These elastic properties of carbon fibres are in turn used to estimate the elastic properties of epoxy matrix composites containing these fibres. Very good agreement is found with experimentally available values of unidirectional ply properties. An excellent correlation between experiments and Finite Element Analyses of the indentation response of carbon fibres is eventually found.
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Vibrational measurement of shear modulus and damping of wood: An application of the Vybris-Torsion device 
Auteur(s): Hu H.-T., Arnould O., Carlier C., Camp G., Lotte Sylvain, Langbour Patrick, Brémaud I.
Conference: 9èmes journées du GDR3544 « Sciences du bois » - Grenoble/Online, 18-20 novembre 2020 (Grenoble (en ligne), FR, 2020-11-18)
Actes de conférence: 9èmes journées du GDR3544 « Sciences du bois » - Grenoble/Online, 18-20 novembre 2020, vol. p. ()
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On the Mapping of the Viscoelastic Properties of Polymer Blends by Multifrequency AFM 
Auteur(s): Leclere Philippe, Ramonda Michel, Arnould O., Pittenger Bede
Conference: 8th Multifrequency AFM Conference (Madrid, ES, 2020-10-27)
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Hygromechanical properties of grenadilla wood (Dalbergia melanoxylon) 
Auteur(s): Alkadri A., Jullien D., Arnould O., Rosenkrantz Eric, Langbour Patrick, Hovasse Louise, Gril J.
(Article) Publié:
Wood Science And Technology, vol. p. (2020)
Ref HAL: hal-02927145_v1
DOI: 10.1007/s00226-020-01215-z
Exporter : BibTex | endNote
Résumé: Grenadilla wood (Dalbergia melanoxylon Guill. & Perr.) is a hardwood species found in Tanzania, Mozambique, and other countries in the tropical part of Africa, especially in the Eastern-Central region. Thanks to its high density and good hygro-scopic stability, it is used in the making of various musical instruments and fine furniture. Due to the scarcity of published data on this wood species, more studies on its properties are needed to improve its processing and use, and even to search for sustainable alternative materials as its trade is increasingly limited by new regulations. This work is focused on the hygromechanical properties, which hold an important role in the applications of this wood: diffusion coefficients and adsorption-desorp-tion curve (both measured at T = 20 • C), swelling-shrinkage coefficients and full orthotropic elastic constants using an ultrasonic method. Results show that grenadilla wood possesses small water diffusion coefficients (from 1.54 ± 0.49 × 10 −7 cm 2 ∕s in T direction to 4.58 ± 0.84 × 10 −7 cm 2 ∕s in L direction), which is probably related to its high density (1250.0 ± 26.2 kg∕m 2); unique equilibrium moisture content (sorp-tion) curve with a lower fiber saturation point (0.173 ± 0.003); smaller swelling-shrinkage coefficients (0.20 ± 0.03 and 0.32 ± 0.05 in T and R directions, respectively); and elastic constants lower in the longitudinal direction (15.56 ± 1.79 GPa) and higher in the transverse ones (5.10 ± 0.46 GPa and 4.05 ± 0.35 GPa in R and T directions, respectively) than what could be expected with a standard model based on the density only. Several explanations were described here, from the effects of a high extractive content to the possibility of a high microfibril and/or fiber angle.
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The Middle Lamella of Plant Fibers Used as Composite Reinforcement: Investigation by Atomic Force Microscopy 
Auteur(s): Melelli Alessia, Arnould O., Beaugrand Johnny, Bourmaud Alain
(Article) Publié:
Molecules, vol. 25 p.632 (2020)
Ref HAL: hal-02466061_v1
DOI: 10.3390/molecules25030632
Exporter : BibTex | endNote
Résumé: Today, plant fibers are considered as an important new renewable resource that can compete with some synthetic fibers, such as glass, in fiber-reinforced composites. In previous works, it was noted that the pectin-enriched middle lamella (ML) is a weak point in the fiber bundles for plant fiber-reinforced composites. ML is strongly bonded to the primary walls of the cells to form a complex layer called the compound middle lamella (CML). In a composite, cracks preferentially propagate along and through this layer when a mechanical loading is applied. In this work, middle lamellae of several plant fibers of different origin (flax, hemp, jute, kenaf, nettle, and date palm leaf sheath), among the most used for composite reinforcement, are investigated by atomic force microscopy (AFM). The peak-force quantitative nanomechanical property mapping (PF-QNM) mode is used in order to estimate the indentation modulus of this layer. AFM PF-QNM confirmed its potential and suitability to mechanically characterize and compare the stiffness of small areas at the micro and nanoscale level, such as plant cell walls and middle lamellae. Our results suggest that the mean indentation modulus of ML is in the range from 6 GPa (date palm leaf sheath) to 16 GPa (hemp), depending on the plant considered. Moreover, local cell-wall layer architectures were finely evidenced and described.
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