Thilo Morgeneyer

Research Director

Center · CMAT

Topic(s): Hydrogen, Nuclear, Polymer, Recycling, Superalloy, Sustainable Development

Keywords

Awards & distinctions

2017 2017 Jean MANDEL Prize
2016 Award for Best Poster at the ICACM2016 Symposium in Compiègne

Team

MEM - Mécanique Expérimentale et Matériaux

Biography

Thilo Morgeneyer is a researcher specializing in the study of fracture and damage mechanisms in metallic and composite materials, with particular expertise in ductile fracture mechanics and multiscale analysis of microstructures. His work focuses on the influence of local stresses, microstructural inhomogeneities, and loading conditions on the mechanical behavior of materials, particularly in industrial contexts such as aerospace and energy. Morgeneyer has contributed to the advancement of in situ experimental methods, such as laminography and synchrotron radiation tomography, coupled with digital image correlation (DIC) techniques and finite element numerical simulations. His research covers a wide range of topics, from the Portevin-Le Chatelier effect in aluminum alloys to hydrogen-induced damage in steels, including the study of cavity coalescence mechanisms and the impact of heat treatments on material toughness. His approach often combines detailed experimental observations with advanced modeling techniques, such as the Gurson-Tvergaard-Needleman (GTN) or Rousselier models, to better understand and predict fracture phenomena.

Publication(s)

2025
Experimental and numerical investigations on the influence of crack-tip constraint on the ductile fracture behavior in nodular cast iron DOI : 10.1016/j.engfracmech.2024.110773
2025
Gurson revisited and multiscale-multimechanisms modeling DOI : 10.1016/j.ijplas.2025.104490
2025
Quantifying damage mechanisms through FE-based void tracking: Application to shear and tension in-situ laminography experiments on AA2198-T851 DOI : 10.1016/j.actamat.2025.120783
2025
Investigating the influence of strain rate on hydrogen embrittlement in steel sub-size tensile specimens using 3D X-ray tomography DOI : 10.1016/j.ijhydene.2025.04.398
2025
Re-straining induced triggering of the Portevin-Le Chatelier effect in recrystallised 2198 T3 and T8 aluminium alloy: Experimental observations and FE simulations for smooth and notched samples DOI : 10.1016/j.ijsolstr.2025.113636
2025
Effect of microstructure on creep mechanical behavior and damage mechanisms of AISI 316L (N) austenitic stainless steels DOI : 10.1016/j.prostr.2025.06.057
2024
Ductile shear damage micromechanisms studied by correlative multiscale nanotomography and SEM/EBSD for a recrystallized aluminum alloy 2198 T8 DOI : 10.1007/s10853-024-09933-6
2024
3D strain heterogeneity and fracture studied by X-ray tomography and crystal plasticity in an aluminium alloy DOI : 10.1016/j.ijplas.2024.104146
2023
Effect of Welding Microstructure on Stress Relaxation Cracking Studied by Controlled Residual Stress Generation in a 316L(N) Austenitic Stainless Steel DOI : 10.1007/s11661-023-07182-x
2023
X-ray microtomography investigation of damage fields ahead of cracks in CT and SENT C-Mn steel samples DOI : 10.1007/s10704-022-00674-8
2023
Hierarchically guided in situ nanolaminography for the visualisation of damage nucleation in alloy sheets DOI : 10.1038/s41598-022-27035-8
2023
Shear loading dominated damage mechanisms and strain localization studied by in situ 3D laminography imaging and Digital Volume Correlation for AA2198-T8 DOI : 10.1016/j.mechmat.2023.104558
2023
A polycrystalline damage model applied to an anisotropic aluminum alloy 2198 under non-proportional load path changes DOI : 10.1016/j.ijplas.2023.103674
2022
3D in situ study of damage during a ‘shear to tension’ load path change in an aluminium alloy DOI : 10.1016/j.actamat.2022.117842
2022
Effects of neutron irradiation and post-irradiation annealing on pop-in crack propagation instabilities in 6061 aluminium alloy DOI : 10.1016/j.jnucmat.2022.153909
2021
Strength, fatigue strength and toughness of dissimilar Ti17–Ti64 linear friction welded joints: Effect of soft surface contamination and depletion of α precipitates DOI : 10.1016/j.msea.2020.139989
2021
On the use of stereo-digital image correlation for the alignment of a fatigue testing machine in accordance with international standards: A feasibility study DOI : 10.1111/str.12382
2021
Nanocavitation mechanisms in deformed High Density PolyEthylene (HDPE) using synchrotron radiation NanoTomography DOI : 10.1016/j.polymer.2021.123959
2021
Ductile damage of AA2024-T3 under shear loading: Mechanism analysis through in-situ laminography DOI : 10.1016/j.actamat.2020.116556
2021
Effect of Lüders and Portevin-Le Chatelier localization bands on plasticity and fracture of notched steel specimens studied by DIC and FE simulations DOI : 10.1016/j.ijplas.2020.102880
2020
Microstructural observations supporting thermography measurements for short glass fibre thermoplastic composites under fatigue loading DOI : 10.1007/s00161-019-00748-4
2020
On the effect of a thermal treatment on the tensile and fatigue properties of weak zones of similar Ti17 linear friction welded joints and parent material DOI : 10.1016/j.matchar.2020.110570
2019
Effect of hardening on toughness captured by stress-based damage nucleation in 6061 aluminum alloy DOI : 10.1016/j.actamat.2019.08.055
2019
On the Origin of the Anisotropic Damage of X100 Line Pipe Steel: Part I—In Situ Synchrotron Tomography Experiments DOI : 10.1007/s40192-019-00165-0
2019
Analysis of fiber orientation and distribution of volumetric strain in polyamide 6-glass fiber composites using cylinder correlation and digital volume correlation methods
2019
A comparative study of image segmentation methods for micromechanical simulations of ductile damage DOI : 10.1016/j.commatsci.2018.11.039
2019
Quantitative Anisotropic Damage Mechanism in a Forged Aluminum Alloy Studied by Synchrotron Tomography and Finite Element Simulations DOI : 10.1155/2019/8739419
2019
Strength and fatigue strength of a similar Ti-6Al-2Sn-4Zr-2Mo-0.1Si linear friction welded joint DOI : 10.1111/ffe.12973
2019
Portevin-Le Chatelier effect triggered by complex loading paths in an Al–Cu aluminium alloy DOI : 10.1080/14786435.2018.1550296
2018
Impact of machine stiffness on ‘‘pop-in’’ crack propagation instabilities DOI : 10.1016/j.engfracmech.2018.08.007
2018
Void growth and coalescence in a magnesium alloy studied by synchrotron radiation laminography DOI : 10.1016/j.actamat.2018.05.026
2018
On the calibration of elastoplastic parameters at the microscale via X-ray microtomography and digital volume correlation for the simulation of ductile damage DOI : 10.1016/j.euromechsol.2018.04.010
2018
3D Stress Fields Versus Void Distributions Ahead of a Notch Tip for Semi-crystalline Polymers DOI : 10.1016/j.prostr.2018.12.367
2018
On deformation and damage micromechanisms in strong work hardening 2198 T3 aluminium alloy DOI : 10.1016/j.actamat.2018.01.026
2018
On the crystallographic, stage I-like, character of fine granular area formation in internal fish-eye fatigue cracks DOI : 10.1016/j.ijfatigue.2017.09.013
2018
Early strain localization in strong work hardening aluminum alloy (2198 T3): 3D laminography and DVC measurement DOI : 10.1007/978-3-319-63028-1_3
2018
Experimental-numerical validation framework for micromechanical simulations DOI : 10.1007/978-3-319-65463-8_8
2018
Effect of void arrangement on ductile damage mechanisms in nodular graphite cast iron: In situ 3D measurements DOI : 10.1016/j.engfracmech.2018.01.008
2018
Recent advances in finite element modelling of ductile fracture at mesoscale DOI : 10.1016/j.promfg.2018.07.167
2018
Evaluation of measurement uncertainties of digital volume correlation applied to laminography data DOI : 10.1177/0309324717748097
2018
Ductile damage mechanism under shear-dominated loading: In-situ tomography experiments on dual phase steel and localization analysis DOI : 10.1016/j.ijplas.2018.06.003
2017
Numerical modeling of ductile fracture at the microscale combined with X-ray laminography and digital volume correlation DOI : 10.1063/1.5008191
2017
A constitutive model accounting for strain ageing effects on work-hardening. Application to a C–Mn steel DOI : 10.1016/j.crme.2017.09.005
2017
Local approach to stress relaxation cracking in a AISI 316L-type austenitic stainless steel: Tomography damage quantification and FE simulations DOI : 10.1016/j.engfracmech.2017.03.050
2017
Voiding Mechanisms in Deformed Polyamide 6 Observed at the Nanometric Scale DOI : 10.1021/acs.macromol.7b00727
2017
Impact of heat treatments of an Al-Mg-Si alloy on instabilities during crack propagation in fracture toughness tests
2017
Strain and damage interactions during ductile tearing: In situ 3D experiments
2017
In Situ Observation of Strained Bands and Ductile Damage in Thin AA2139-T3 Alloy Sheets DOI : 10.1016/j.piutam.2017.03.009
2017
Fatigue crack initiation mechanisms in ultra-high strength steel
2017
On the choice of boundary conditions for micromechanical simulations based on 3D imaging DOI : 10.1016/j.ijsolstr.2017.02.018
2017
Numerical validation framework for micromechanical simulations based on synchrotron 3D imaging DOI : 10.1007/s00466-016-1357-0
2017
Interaction of the Portevin–Le Chatelier phenomenon with ductile fracture of a thin aluminum CT specimen: experiments and simulations DOI : 10.1007/s10704-017-0203-5
2017
Prediction of residual lifetime of high density polyethylene pipes based on the micro-mechanisms of creep fracture
2016
Comparison of voiding mechanisms in semi-crystalline polyamide 6 during tensile and creep tests DOI : 10.1016/j.polymertesting.2015.11.019
2016
Intergranular damage during stress relaxation in AISI 316L-type austenitic stainless steels: Effect of carbon, nitrogen and phosphorus contents DOI : 10.1016/j.actamat.2015.11.004
2016
Structural versus microstructural evolution of semi-crystalline polymers during necking under tension: Influence of the skin-core effects, the relative humidity and the strain rate DOI : 10.1016/j.polymertesting.2016.09.012
2016
Slant strained band development during flat to slant crack transition in AA 2198 T8 sheet: in situ 3D measurements DOI : 10.1007/s10704-015-0052-z
2016
Three dimensional quantification of anisotropic void evolution in deformed semi-crystalline polyamide 6 DOI : 10.1016/j.ijplas.2016.04.001
2016
Real-time image-content-based beamline control for smart 4D X-ray imaging DOI : 10.1107/S1600577516010195
2016
In situ 3D Synchrotron Laminography Assessment of Edge Fracture in Dual-Phase Steels: Quantitative and Numerical Analysis DOI : 10.1007/s11340-015-0076-3
2016
3D Damage Micromechanisms in Polyamide 6 Ahead of a Severe Notch Studied by in Situ Synchrotron Laminography DOI : 10.1002/macp.201500316
2016
Numerical investigation of dynamic strain ageing and slant ductile fracture in a notched specimen and comparison with synchrotron tomography 3D-DVC DOI : 10.1016/j.prostr.2016.06.422
2016
On strain and damage interactions during tearing: 3D in situ measurements and simulations for a ductile alloy (AA2139-T3) DOI : 10.1016/j.jmps.2016.07.012
2015
Fatigue lifetime and tearing resistance of AA2198 Al-Cu-Li alloy friction stir welds: Effect of defects DOI : 10.1016/j.ijfatigue.2014.07.001
2015
Damage based model to study the effect of notch introduction technique on the J-integral value of PolyOxyMethylene DOI : 10.1016/j.engfracmech.2015.08.031
2015
On the use of regularized DVC to analyze strain localization DOI : 10.1007/978-3-319-06986-9_17
2015
Three-dimensional characterization of fatigue-relevant intermetallic particles in high-strength aluminium alloys using synchrotron X-ray nanotomography DOI : 10.1080/14786435.2015.1076940
2014
In situ laminography study of three-dimensional individual void shape evolution at crack initiation and comparison with Gurson-Tvergaard-Needleman- type simulations DOI : 10.1016/j.actamat.2014.06.029
2014
In situ 3-D observation of early strain localization during failure of thin Al alloy (2198) sheet DOI : 10.1016/j.actamat.2014.01.033
2014
Localized strain field measurement on laminography data with mechanical regularization DOI : 10.1016/j.nimb.2013.09.033
2014
Microstructural Characterization of Internal Welding Defects and Their Effect on the Tensile Behavior of FSW Joints of AA2198 Al-Cu-Li Alloy DOI : 10.1007/s11661-014-2537-1
2014
Nanovoid morphology and distribution in deformed HDPE studied by magnified synchrotron radiation holotomography DOI : 10.1016/j.polymer.2014.10.022
2013
3D synchrotron laminography assessment of damage evolution in blanked dual phase steels
2013
Three-dimensional quantitative in situ study of crack initiation and propagation in AA6061 aluminum alloy sheets via synchrotron laminography and finite-element simulations DOI : 10.1016/j.actamat.2013.01.035
2013
Local approach of fracture on semi-crystalline polymers: Contribution of X-ray laminography technique
2013
3D Digital Volume Correlation of Synchrotron Radiation Laminography Images of Ductile Crack Initiation: An Initial Feasibility Study DOI : 10.1007/s11340-012-9660-y
2013
Combining X-Ray microtomography with the finite elements method to study damage and cracking in stuctural materials DOI : 10.1002/9781118663547.ch142
2013
Failure of magnesium sheets under monotonic loading: 3d examination of fracture mode and mechanisms DOI : 10.1007/s10704-013-9863-y
2013
Fatigue life and initiation mechanisms in wrought Inconel 718 DA for different microstructures
2013
Three-dimensional damage evolution measurement in EB-PVD TBCs using synchrotron laminography DOI : 10.1007/s11085-012-9333-3
2013
Combining X-ray microtomography with the finite elements method to study damage and cracking in stuctural materials
2013
Effect of welding defects on plastic behaviour and fatigue lifetime of friction stir welded Al-Cu-Li alloy
2013
Feasibility study of 3D digital volume correlation of synchrotron radiation laminography data for displacement field measurement during ductile crack initiation DOI : 10.1007/978-1-4614-4235-6_29
2012
Bulk evaluation of ductile damage development using high resolution tomography and laminography DOI : 10.1016/j.crhy.2011.12.009
2012
Effect of multiaxial stress state on morphology and spatial distribution of voids in deformed semicrystalline polymer assessed by X-ray tomography DOI : 10.1021/ma3005247
2012
Three-dimensional investigation of thermal barrier coatings by synchrotron-radiation computed laminography DOI : 10.1016/j.scriptamat.2011.12.021
2012
Synchrotron and neutron laminography for three-dimensional imaging of devices and flat material specimens DOI : 10.3139/146.110668
2011
Plastic flow and ductile rupture of a 2198 Al-Cu-Li aluminum alloy DOI : 10.1016/j.commatsci.2010.06.029
2011
Flat to slant ductile fracture transition: Tomography examination and simulations using shear-controlled void nucleation DOI : 10.1016/j.scriptamat.2011.09.004
2011
Ductile crack initiation and propagation assessed via in situ synchrotron radiation-computed laminography DOI : 10.1016/j.scriptamat.2011.09.005
2011
Multiaxial stress state assessed by 3D X-Ray tomography on semi-crystalline polymers DOI : 10.1007/978-1-4614-0228-2_7
2011
In-situ synchrotron-radiation computed laminography observation of ductile fracture DOI : 10.1007/978-1-4614-0228-2_3
2010
Ductile rupture of prestrained X100 pipeline steel sheets
2010
Study of the flat to slant crack transition in ductile thin sheet material: Simulations and experiments
2010
Effect of friction stir weld defects on fatigue lifetime of an Al-Cu-Li alloy (AA-2198
2010
Effect of joint line remnant on fatigue lifetime of friction stir welded Al-Cu-Li alloy DOI : 10.1179/136217110X12813393169453
2010
Influence of strain rate on P92 microstructural stability during fatigue tests at high temperature DOI : 10.1016/j.proeng.2010.03.230
2010
Damage observation in a high-manganese austenitic TWIP steel by synchrotron radiation computed tomography DOI : 10.1016/j.scriptamat.2010.08.042
2010
Damage of semicrystalline polyamide 6 assessed by 3D X-ray tomography: From microstructural evolution to constitutive modeling DOI : 10.1002/polb.22043
2009
Experimental and computational analysis of toughness anisotropy in an AA2139 Al-alloy for aerospace applications
2009
Experimental and numerical analysis of toughness anisotropy in AA2139 Al-alloy sheet DOI : 10.1016/j.actamat.2009.04.046
2008
Evolution of voids during ductile crack propagation in an aluminium alloy sheet toughness test studied by synchrotron radiation computed tomography DOI : 10.1016/j.actamat.2007.12.019
2008
Effect of prestrain on ductility of a X100 pipeline steel
2008
Quench sensitivity of toughness in an Al alloy: Direct observation and analysis of failure initiation at the precipitate-free zone DOI : 10.1016/j.actamat.2008.02.021
2006
Experimental analysis of toughness in 6156 AL-alloy sheet for aerospace applications DOI : 10.4028/www.scientific.net/msf.519-521.1023

Projects

2024-2028 EU Hyway Project Co-Investigator The main objective of HyWay is to develop adaptive multiscale material modelling and characterisation suites for assessing interactions between hydrogen and advanced metallic materials and demonstrate their capabilities on hydrogen storage and transport components. Our ambition is to enable industries to be more efficient when developing and using new advanced materials, shorten the materials innovation cycle, seamlessly merge materials modelling and characterisation approaches along value chains, and create a robust material research ecosystem platform. https://hywayproject.eu/project/
2024-2028 ANR Recycal Partner Impact des impuretés sur la germination de l'endommagement et la formabilité des alliages d'aluminium recyclé – RECYCAL Le projet RECYCAL a pour but de comprendre et de modéliser les mécanismes d’endommagement à l’œuvre dans les alliages d’aluminium issus du recyclage lors d’un chargement en déformation plane. Par rapport aux références utilisées actuellement dans les domaines du transport ou de l’emballage, ces alliages possèdent des teneurs plus élevées en impuretés, notamment en fer, ce qui conduit souvent à une baisse de propriétés. RECYCAL est un partenariat entre l’entreprise Constellium, le Centre des Matériaux, le CEMEF et le laboratoire SIMaP. L’objectif principal est de prédire l’impact sur la ductilité des caractéristiques microstructurales liées aux particules intermétalliques (taille, morphologie, nature, distribution spatiale) et de leur environnement (dureté de la matrice, orientations cristallographiques des grains) en combinant des caractérisations 3D à différentes résolutions et des modélisations multi-échelles. L’effet du trajet de chargement sera également investigué in-situ en comparant la traction en déformation plane et le pliage sur éprouvettes miniaturisées sous le faisceau de rayons X au synchrotron, puis en étendant à des chargements industriels complexes, combinaisons de ces chargements élémentaires, par simulation éléments finis (EF). Le projet sera organisé en six lots complémentaires : 1- Fabrication des matériaux et caractérisation initiale ; 2- Observation et quantification de l’endommagement en traction plane ; 3- Observation et quantification de l’endommagement en pliage ; 4- Simulations micromécaniques en champ complet à partir des microstructures réelles imagées par tomographie ; 5- Construction d’un critère d’endommagement incluant les données microstructurales pertinentes issues des observations in-situ (lots 2 et 3) et des simulations sur volume élémentaire représentatif (lot 4) (comparaison approche statistique classique et réseau de neurones) ; 6- Transfert à l’échelle industrielle via des simulations EF utilisant le critère proposé au lot 5. https://anr.fr/Projet-ANR-23-CE08-0033
2018-2022 ANR LAMBDA Lead Investigator In-Situ X-ray LAMinography with Bi-axial Loads for the Multiscale Investigation of DAmage Formation in Materials for Transportation – LAMBDA In the pursuit of lighter materials and optimized thin-walled components for transportation, knowledge about the characteristic ductile damage mechanisms in metal sheets is key.As the study of damage in materials has, up to now, been focussed on proportional loading, the strain-damage interaction is not understood for the highly application-relevant bi-axial loading with load path changes. Thus, our proposal aims at three-dimensional (3D) imaging of the microstructure inside flat sheet specimens evolving during material testing under such loads. For this, we extend the capability of in situ synchrotron laminography to overcome inherent insufficiency of other 3D techniques for such kind of samples. It shall be developed into a unique multiscale approach from a few hundred micrometres down to nanometre scale to determine the ductile damage nucleation and growth kinetics. Such hierarchical 3D data will serve as valuable input for microscopic simulations and the formulation and validation of continuum damage models suited to predict engineering-relevant mechanical properties. https://anr.fr/Project-ANR-17-CE08-0051
2025-2029 « Matériaux, Transition écologique, Recyclage et Imagerie X – MATRIX » « Programmes d’amorçage de l’Université PSL » Lead Investigator The MATRIX starter program aims to develop at PSL cutting-edge research around the materials and technologies necessary for the ecological transition. It brings together the knowledge and experience of 14 laboratories from 5 PSL members as well as the Synchrotron SOLEIL research center, located close to the partners near Paris. The large multidisciplinary consortium united behind MATRIX makes it possible to address all aspects of materials engineering and innovation in support of the necessary changes to our economy and our industry. The proposed research will be organized into 4 axes: (i) innovation in material recycling (ii) materials for a circular economy (iii) materials for the energy transition (iv) materials for sustainable construction. In addition, a new 3D material characterization platform will be created at Mines Paris and mutualized between all partners as well as facilitated access to Synchrotron SOLEIL for cutting edge characterizations. This project aims to produce a real and strong impact in the field of the ecological transition. It will contribute to fostering a virtuous cycle where material waste can be seen as a resource and knowledge-based innovation as a way to reduce our footprint on the environment while helping to strengthen our industry. This program will also boost PSL industrial research by establishing or consolidating state-of-the-art know-how to tackle industrial issues on extremely important topics for the years to come, such as recycling, low impact materials or sustainable construction.

Teaching

"Fracture Mechanics" dans MAGIS - parcours du master SGM de PSL

2020 – 2026 Course Director

This teaching unit dealt with the main fracture mechanisms (brittle fracture, ductile fracture, fatigue, stress-corrosion...) that can compromise structural integrity and with available modelling approaches and their limits. It shows how fracture mechanics can allow predictions about the reliability, damage tolerance, durability and security of structural components, whatever their constitutive material and geometry . Through excercice sessions, lab sesssions and computer sesssions, the students learn how to recognize a fracture mechanism from fractographic observations, how to analyze service loads, how to reproduce it in lab experiments, how to compute the crack tip stress and strain fields and how to use it to predict crack paths and growth kinetics.

Aspects microscopiques et macroscopiques du comportement mécanique des métaux - CNAM

2019 – aujourd'hui Course Director

Objectifs pédagogiques Identifier les phénomènes fondamentaux mis en jeu dans les alliages métalliques (structure cristalline, défauts cristallins, mécanismes de déformation). Présenter des outils d'ingénieurs pour quantifier les phénomènes fondamentaux (choix des paramètres de traitement thermique, etc.) Résoudre efficacement les problèmes de métallurgie qui se posent dans la pratique. Dans cette partie, l'accent est mis sur le comportement mécanique et sur la mise en forme par déformation plastique des métaux.

PhD supervision

2024 Synchrotron tomography study of hydrogen embrittlement mechanisms in steel for transport and storage applications PILLON Gianpaolo
2024 Study of damage in recycled Al alloys through correlative 4D experiments and simulations VERNET Gabrielle
2024 Characterization of Hydrogen Embrittlement Damage Mechanisms in Storage and Transport Materials: Mini-Specimen Approach BALLMANN DE CAMPOS Eduardo
2023 The effect of different processing routes on the high-temperature resistance of stainless steel for very long service durations BEN BETTAIEB Marwa
2022 Machine learning modeling of nucleation and damage, 4D experimental data, and micromechanical calculations RIJNDERS Berjo
2021 Polycrystalline effects on the interaction between deformation and damage: 4D measurements and finite-element calculations of microstructures GILLE Maryse
2019 The effect of welding on relaxation cracking in AISI 316L(N) austenitic stainless steel PY RENAUDIE Baptiste
2018 Study of ductile damage under complex loading and low triaxiality conditions using synchrotron 3D imaging and finite element calculations KONG Xiang
2017 Stress relaxation cracking of austenitic stainless steel AISI 316L(N) KOEDINGER Thomas
2016 Mechanical characterization of linear friction welded titanium alloys GARCIA Juan-Manuel
2015 Study of fatigue behavior and associated mechanisms in a very high-strength steel for aeronautical applications ABDESSELAM Hayat
2015 Understanding and modeling of toughness tests with pop-in: application to 6061-T6 aluminum and influence of neutron irradiation PETIT Tom