ESPCI web site
Séminaires
Le séminaire hebdomadaire du laboratoire PMMH a lieu tous les vendredis à 11h, au premier étage Barre Cassan, campus Jussieu (plan).
Alice Pelosse
Stéphane Perrard
Etienne Reyssat
Virgile Thiévenaz
PMMH
BARRE CASSAN
BAT A 1ER ETAGE CASE 18
7 QUAI SAINT BERNARD
75005 PARIS
France
Tel : (33) 1 40 79 45 22
Séminaire PMMH - Christophe Denoual, CEA
A path to model complex displacive transitions
C. Denoual1,2, N. Bruzy1,2
1-CEA, DAM, DIF, F-91297 Arpajon, France
2-Université Paris-Saclay, LMCE, F-91680 Bruyères-le-Châtel, France
Under shock loading, crystalline metals can accommodate stresses through very rapid microstructural transitions such as deformation twinning or martensitic phase transitions. These transformations occur via a collective movement of atoms (referred to as a "military" transition), typically resulting in a microstructure composed of long lamellae aligned along specific planes known as habit planes. The very limited number of crystallographic orientations observed during these transitions (e.g., 12 for twinning under shock in tantalum) arises from the limited number of possible deformation paths associated with these transitions (6 for tantalum twinning). Since these transitions lead to another well-defined crystalline structure, successive deformations can interlock, creating microstructures of remarkable complexity.
In this presentation, we will demonstrate that modeling such a transition can be achieved through a "reaction pathway graph" that represents the first n minimal-energy pathways connecting one stable phase to another. Several examples illustrating the richness of this approach will be discussed, particularly in the context of tantalum twinning under rapid loading conditions. In that case, deformation twinning is in competition with plasticity through the motion of dislocations, emphasizing the need for a detailed coupling between the graph of reaction pathways and crystal plasticity description.
Séminaires (3)
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Séminaire PMMH — Mathis Guéneau, Max Planck Institute for the Physics of Complex Systems
Vendredi 2 octobre de 11h00 à 12h00 - Salle réunion PMMH 1
Spatiotemporal Characterization of Active Dynamics in Channels : Theory and Experiments
Swimming microorganisms often live in confined, complex environments, where they transition between bulk and near-surface dynamics. Their dynamics can be quantified in terms of first-passage statistics. In this talk, I will first consider active Brownian dynamics between two walls. Using a systematic expansion, (…) -
Séminaire PMMH — Lorène Champougny, LGC Toulouse
Vendredi 9 octobre de 11h00 à 12h00 - Salle réunion PMMH 1
The Fluid Mechanics of Splatter Painting
In art, splatter painting consists in subjecting a paint-loaded brush to an acceleration (for example by “flicking” the brush or tapping its handle) to detach paint droplets or filaments. Those are projected onto the substrate to be painted, leaving filamentary or spotty patterns (Fig. 1a). In this technique, (…) -
Séminaire PMMH - Ada Altieri (MSC, Paris)
Vendredi 20 novembre de 11h00 à 12h00 - Salle réunion PMMH 1
From disordered Generalized Lotka-Volterra models to gut microbiome complexity
Inferring species interactions in highly heterogeneous ecological communities and developing a robust, predictive theory of ecological stability remain major challenges, due both to the amount of data required and the complexity of the underlying interaction network. In this talk, I will present a high-dimensional (…)
Instructions générales pour les conférenciers
Le public du séminaire est très hétérogène (rien qu’au PMMH nous travaillons sur des thématiques très diverses, mécanique des fluides, des milieux granulaires, des solides, physique statistique, physique du mouillage, micro-fluidique, biophysique,...) l’objectif est donc de ne pas faire un séminaire trop spécialiste : au moins la première moitié du séminaire à un niveau accessible pour celui qui ne connaît rien sur le sujet.
Le séminaire a lieu à 11h. rendez-vous 15 minutes avant pour installer et tester la projection.
Le séminaire dure environ 45 minutes pour laisser un peu de temps pour discuter à la fin.
- Séminaires ESPCI-ENS de biophysique
- Séminaires du Département de Physique de l’ENS
- Séminaires du Laboratoire d’Hydrodynamique de l’X
- Séminaire de Mécanique d’Orsay (page web FAST)
- Séminaire de Mécanique d’Orsay (page web LIMSI)
- Séminaire de Mécanique des Fluides de l’Institut Jean le Rond d’Alembert
- Séminaires du laboratoire MSC, Paris VII
- Séminaires Gulliver
Soutenances de thèse
Auriane Huyghues-Despointes : 22/09 - 14h30
Sébastien Kuchly : 23/09 - 14h
Juliette Michaud : 28/09 - 14h
Diane Komaroff : 02/10 - 14h
Marc Vacher : 13/10
Jules Tampier : 16/10 - 13h30
Alex Le Guen : 01/12 - 14h
Séminaires café (internes, tous les jeudis)
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