Tesi sul tema "Acier au carbone – Propriétés mécaniques"
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Fallot, Guillaume. "Rôle du carbone lors de la nitruration d’aciers de construction et influence sur les propriétés mécaniques". Thesis, Paris, ENSAM, 2015. http://www.theses.fr/2015ENAM0029/document.
During the nitriding treatment, the diffusion of nitrogen in the steels causes the transformation of initial carbides into nitrides. During this transformation, carbon is released into the ferritic matrix. The experimental study has highlighted that the decarburization of the nitride layer occurs regardless of the type of nitriding and could reach 20% when the nitriding surface is not composed of compound layer This decarburization is induced by the reaction of the carbon released during the transformation of the cementite, with the hydrogen produced by the decomposition of ammonia to give a carburized species ?, this reaction occurs as long as any compound layer exists at the surface of the sample. This carbon redistribution has an influence on the microstructure and the residual stresses of the nitride layers. Based on experimental results, this phenomenon has been implemented in the nitriding simulation model developed in the laboratory. This implementation focuses on initial and boundary conditions obtained by complementing the experimental results with a thermodynamic simulation, to simulate nitrogen and carbon profiles close to those obtained experimentally. The model also calculates the volume change due to ? the precipitation and calculates the fields of residual stresses generated at the nitriding temperature and their evolution during cooling.. The multiphase character of the material is taken into account; the simulation allowing knowing the residual stresses in the ferrite, the precipitates and macroscopic residual stresses through a micromechanical model of scale transition like self-consistent. This multiphysics approach is applicable to all alloy carbon steels (Cr, Mo, V). This model has specifically been applied to industrial grade 33CrMoV12-9. The entire study allows understanding the influence of carbon on the mechanical properties of nitrided layers and the development of an industrial nitriding cycle based on experimental results and simulation
Oliveira, Anicio Costa Isadora Maria. "Relations entre la microstructure, les propriétés mécaniques et électromagnétiques de fils d'acier au carbone traités thermomécaniquement". Thesis, Lille 1, 2020. http://www.theses.fr/2020LIL1R047.
Pearlite is a common constituent of a large variety of high strength steel grades typically used in many structural engineering applications, which demand a good combination of high strength and ductility. With the increasing requirements for product quality and in-service reliability, the non-destructive inspection of materials enables the evaluation of their properties including electromagnetic methods, such as eddy current testing (ECT). However, the influence of microstructural parameters on the physical properties indirectly measured by an electromagnetic sensor has not yet been completely elucidated. The objective of the present work is thereby to understand the relations between microstructure, mechanical properties, and electromagnetic behavior of carbon steel wires submitted to different thermomechanical treatments. It aims also at improving the knowledge of the physical and mechanical metallurgy of these steels. The effect of microstructure and plastic deformation on the electromagnetic responses of different steels with various tensile strengths was investigated through resistivity down to 2 K and magnetic measurements, as well as by ECT. In addition, magnetic domains could be imaged by magnetic force microscopy despite the complex microstructures. The electromagnetic responses changed according to the electrical conductivity and magnetic permeability variations of each material, which were mainly related to changes in the volume fraction, distribution, and morphology of the cementite phase within the α-ferrite matrix. The increase of carbon concentration enhances the localization of electrons at the atomic sites, assisting the covalent character of interatomic bonds and thereby reducing the conductivity of steels. Besides, the α-Fe3C interfaces that act as a physical barrier for dislocation slip in ferrite, affecting as well the main free-path for conductive electrons and magnetic domain walls displacements within the material. Conductivity and permeability increased in the order of martensite, sorbite, pearlite, proeutectoid ferrite-pearlite, spheroidite, and ferrite microstructures. Also, the electrical and magnetic behavior of fully pearlitic steels was observed to depend on the deformation resulted from the cold-drawing and in-service application where fatigue may occur. Low-cycle fatigue experiments have pointed out that the resistance can be managed by relevant thermo-mechanical treatments. The potentiality of ECT was highlighted as a characterization tool of the microstructural state and mechanical properties of steel wires during manufacturing processes or in-service environment. Finally, this technique has been shown to be useful for monitoring cyclic elastic deformation and plastic accommodation of pearlitic steels responding to fatigue-loading conditions
Oliveira, Anicio Costa Isadora Maria. "Relations entre la microstructure, les propriétés mécaniques et électromagnétiques de fils d'acier au carbone traités thermomécaniquement". Electronic Thesis or Diss., Université de Lille (2018-2021), 2020. http://www.theses.fr/2020LILUR047.
Pearlite is a common constituent of a large variety of high strength steel grades typically used in many structural engineering applications, which demand a good combination of high strength and ductility. With the increasing requirements for product quality and in-service reliability, the non-destructive inspection of materials enables the evaluation of their properties including electromagnetic methods, such as eddy current testing (ECT). However, the influence of microstructural parameters on the physical properties indirectly measured by an electromagnetic sensor has not yet been completely elucidated. The objective of the present work is thereby to understand the relations between microstructure, mechanical properties, and electromagnetic behavior of carbon steel wires submitted to different thermomechanical treatments. It aims also at improving the knowledge of the physical and mechanical metallurgy of these steels. The effect of microstructure and plastic deformation on the electromagnetic responses of different steels with various tensile strengths was investigated through resistivity down to 2 K and magnetic measurements, as well as by ECT. In addition, magnetic domains could be imaged by magnetic force microscopy despite the complex microstructures. The electromagnetic responses changed according to the electrical conductivity and magnetic permeability variations of each material, which were mainly related to changes in the volume fraction, distribution, and morphology of the cementite phase within the α-ferrite matrix. The increase of carbon concentration enhances the localization of electrons at the atomic sites, assisting the covalent character of interatomic bonds and thereby reducing the conductivity of steels. Besides, the α-Fe3C interfaces that act as a physical barrier for dislocation slip in ferrite, affecting as well the main free-path for conductive electrons and magnetic domain walls displacements within the material. Conductivity and permeability increased in the order of martensite, sorbite, pearlite, proeutectoid ferrite-pearlite, spheroidite, and ferrite microstructures. Also, the electrical and magnetic behavior of fully pearlitic steels was observed to depend on the deformation resulted from the cold-drawing and in-service application where fatigue may occur. Low-cycle fatigue experiments have pointed out that the resistance can be managed by relevant thermo-mechanical treatments. The potentiality of ECT was highlighted as a characterization tool of the microstructural state and mechanical properties of steel wires during manufacturing processes or in-service environment. Finally, this technique has been shown to be useful for monitoring cyclic elastic deformation and plastic accommodation of pearlitic steels responding to fatigue-loading conditions
Danylova, Olena. "Etude des relations microstructure/propriétés mécaniques des aciers bas carbone microallies, en fonction des paramètres du traitement thermique et thermomécanique". Lyon, INSA, 2000. http://www.theses.fr/2000ISAL0038.
Low carbon micro-alloyed steels produce today a lot of metallic materials having high level of potentialities because of the possibility to use an elaboration processing more economic in association with interesting mechanical properties. Especially ' such steels have high mechanical strength coupled with a high toughness and a low brittle/ductile transition temperature. Our study has consisted in approach of characterization at two levels: - First one is a micro structural characterization by using of optical microscopy, scanning electron microscopy, transmission electron microscopy and microanalysis devices. - the second corresponds to a mechanical testing investigation such as tensile test, Charpy-V or U-notched test, BDWTT test, nano-hardness. The finality of these investigations has to carry out the correlation between the varied types of “bainitic” microstructures and the mechanical properties. The mixing of the bill type bainite and the tempered martensite provides the better compromise between the requirements asked for applications. However, this compromise is accessible only with the contribution of the micro-alloyed elements, which originate a precipitation under the form of the carbonitrides. These last contribute to the grain refinement in steels. This condition is absolutely necessary in order to have a high level of mechanical properties
Deshayes, Pascal. "Conséquences du refroidissement accéléré doux après laminage contrôlé sur la microstructure et les propriétés mécaniques d'aciers à 0,1% de carbone". Lille 1, 1995. http://www.theses.fr/1995LIL10029.
Van, Duysen Jean-Claude. "Relations entre la microstructure et les propriétés mécaniques d'un acier ferritique au chrome-molybdène à basse teneur en carbone de type Z10 CD Nb V9-2". Paris 11, 1987. http://www.theses.fr/1987PA112133.
Gutier, Patrick. "Pulvérisation cathodique magnétron en condition réactive et propriétés mécaniques de revêtements duplex d'acier inoxydable enrichis en azote, carbone et oxygène". Vandoeuvre-les-Nancy, INPL, 2000. http://www.theses.fr/2000INPL042N.
This work deals with the synthesis, the physico-chemical and mechanical caracterisation of coatings obtained by cathodic magnetron sputtering of a metallic austenitic stainless steel target in different argon - reactive gas (nitrogen, methan or oxygen) mixtures. The metastable solid solutions which are nitrogen, carbon or oxygen supersatured, as weIl as the ceramic compound of oxide type (Fe, Cr, Ni)₃O₄, with their different crystalline or amorphous structures are studied by means of the main diffraction techniques of structural analysis and physical methods of chemical analysis. The second part of this work aims to point out the complete mechanical properties of the different coatings and composite (coating + substrat). The intrinsic properties of the different coatings were first studied in relation with the elaboration parameters and structural properties. Vickers indentation as well as single pass and triboscopic multipass scratch testing were then performed on the three type of N, C, 0 doped coatings, in order to establish a relation between the brittleness or ductility and the tribological behaviour (friction, wear)
Avila, de oliveira silva Lais. "Investigation de l’effet du gradient microstructural généré pendant le patentage sur les propriétés mécaniques finales des fils d’acier perlitiques". Electronic Thesis or Diss., Centrale Lille Institut, 2022. http://www.theses.fr/2022CLIL0007.
: Pearlitic steels could appear to be a simple and classic microstructure, with a rather simple eutectoid composition containing twophases (cementite and ferrite) in a lamellar distribution. However, they feature a hierarchical microstructure, which is composed of nodulesthat present the same crystallography and are grain-equivalent, then the nodules comprise the colonies that contain the parallel ferrite andcementite lamellas at a nanometric scale. As a result, pearlitic steels offer high strength and ductility at a reasonable cost, which fits verywell for various structural and reinforcement applications, e.g., steel core, bridge cables, wire ropes, springs…Although pearlitic steels areknown and vastly studied for over 150 years, it could appear outrageous to still propose manners of improving their mechanical properties.However, some options have not yet been considered such as the microstructural gradient or the control of the pearlite morphologies. Themicrostructural gradient concept has been widely explored in simple microstructure in steels, such as ferrite or austenite, but it is morecomplicated to export it in the pearlitic steel. The present Ph.D. aims to investigate the feasibility of producing a microstructural gradient infully pearlitic steels and of controlling the pearlite morphology. It is sought the understanding of the involved metallurgical mechanisms andthe impact on the mechanical properties, especially fatigue, considering the final application of this material. The control of themicrostructure and the gradient is based on the transformation of austenite into pearlite and, therefore, all the parameters that couldinfluence this transformation must be studied. It includes heat treatment parameters (heating rates, cooling rates, cooling modes,temperature of transformation…) and materials ones (initial interlamellar spacing, deformation state of pearlite…). The spacing between theferrite and cementite lamella, known to govern the mechanical properties of pearlitic steels, varies with the transformation temperature,which results in coarse and fine pearlite when transformed at high or low temperatures, respectively. It is found that a microstructuralgradient of interlamellar spacing is possible to be formed but is limited by the rod diameter. Using the dilatometer, it was successfullyprocessed in a 6 and 12 mm diameter rod. The gradient-containing wires were then drawn and the mechanical properties before and afterdrawing are compared to assure that the gradients formed during the heat treatment of the 6 mm diameter wires are still present on the2.25 mm final diameter wires. The morphology of pearlite has also been modified by control of heat treatments using continuous andisotherm cooling. Divorced, connected and well-aligned perfect pearlites with the same interlamellar distance have been processed. It turnsout that the morphology of the monolithic pearlite specimen has a higher impact on cyclic plasticity than the presence of a gradient. Theresults obtained in this Ph.D. gave rise to discussions on the pearlitic transformation under continuous and isotherm cooling, on themechanisms controlling the morphology of pearlite (mostly divorced or lamellar), on the phenomena happening during heating,(recrystallization, recovery, and spheroidization), and also on the mechanisms of plasticity of pearlite. Finally, the feasibility of the productionof the gradients by real cooling technologies is assessed by transforming the wires in a pilot line. It is of most interest that the gradients areproduced by alternative cooling technologies since the lead patenting technique is not the most environmentally friendly, although the mostwidely used
Wauthier, Aurélie. "Observation expérimentale et prévision des paramètres de la déformation déterminants pour la genèse des textures cristallographiques lors de la recristalisation des tôles minces d'aciers à basse teneur en carbone". Paris 13, 2008. http://www.theses.fr/2008PA132010.
The aim of this study is to understand and to model, on physical bases, metallurgical and mechanical phenomena that induce changes in crystallographic textures. Microscopic and textural characterizations have been performed on an IF steel during its industrial process: in the hot band state, then after cold rolling and finally after recrystallisation. Deformation heterogeneities characterization like the modeling has been realized at different scales. The parameters extracted from experimental work, allow an estimation of the fragmentation that occurs in some specific crystallographic orientations. These results are in accordance with the stored energy estimation realized by XRD with, in average, two times more energy in the γ-fibre grains than in the α-fibre grains after high cold-rolling levels, but with low differences for low thickness reductions. A hierarchy of the fragmentation F is proposed such as F{100}<110> < F{112}<110> < F{111}<110> < F{111}<112> < F{554}<225>
Alwan, Raad Aboud. "Analyse des évolutions structurales et du comportement mécanique d'un acier au chrome-nickel-molybdène à très bas carbone du type Z1CNDA 12-09-02, en fonction des traitements thermiques". Paris 11, 1989. http://www.theses.fr/1989PA112002.
We have studied the structural behavior of a stainless steel capable of age hardening, with a very low carbon content. The martensitic alloy concerned by this research has the following composition : Fe-11. 7 Cr-9. 2 Ni-1. 99 Mo-0. 71 Al-0. 34Ti. The thermal treatments have been undertaken in the temperature range of -160°C and 1150°C. The kinetics of the austenitic transformation and the volumic fraction of reversed austenite stabilizes at ambient temperature have been caracterized as a function of the treatment conditions (isothermal and/or isochronal). During isothermal tempering three stages of hardening may occure before the overaging phenomenon and the formation of reversed austenite. Finally, interesting mechanical properties (Rm and R0. 002) and the improvement of A % and KCV for this alloy, can be obtained when the tempering is performed in the range of 525-550°C, the increase in ductility and toughness being obtained to the detriment of a small decrease in mechanical proof
Villegas, Randolfo. "Genèse de la ferrite aciculaire dans les aciers à moyen carbone microalliés au vanadium. Morphologie fractale en relation avec les propriétés mécaniques". Thesis, Vandoeuvre-les-Nancy, INPL, 2007. http://www.theses.fr/2007INPL086N/document.
Medium carbon vanadium microalloyed steels have been developed to obtain new microstructures, mainly formed of acicular ferrite (AF). Controlling the chemical composition and (0.1-0.3 % V) and the cooling rates (2.0 °Cs-1) lead to AF fractions up to 80 %. An empirical parameter, the ferritisant power, P, has been introduced to evaluate the combined effect of chemical composition and cooling conditions. Scanning (SEM) and transmission (TEM) electron microscopy investigations indicate that AF develops from proeutectoid ferrite enveloping MnS inclusions. An interphase precipitation of vanadium carbo-nitrides, V(C,N) has been identified. It is suggested that this precipitation is at the origin of carbon depletion in the austenitic matrix surrounding the AF plates. The formation of the AF is then enhanced by an autocatalytic effect. The fractal nature of AF has been determined by SEM and TEM characterisations. Fractal dimensions, D, and cut off lengths have been derived by the counting box method applied to SEM images. Mechanical tests conducted in isothermal and quasistatic conditions reveal that mechanical properties of AF are of the same grade of that of bainitic microstructures. Experimental strain-stress curves are described by the Hollomon law. The work hardening of the studied microstructures increases with the AF fraction. The mechanical properties have been linked to the fractal dimension by the following exponential relation : [delta]M = c exp [[alpha] (D -2)], where M represents the mechanical property (Re, Rm, etc.) and c and [alpha] are constants parameters
Pushkareva, Irina. "Évolution microstructurale d'un acier Dual Phase. Optimisation de la résistance à l'endommagement". Thesis, Vandoeuvre-les-Nancy, INPL, 2009. http://www.theses.fr/2009INPL084N/document.
In the automotive industry current environmental concerns require that the vehicle fuel consumption and CO2 emissions should be reduced as much as possible. It is therefore advantageous to reduce the weight of body in white components by replacing existing parts with higher strength, thinner gauge alternatives with equivalent or improved functional properties. Dual Phase (DP) steels are a class of high-strength low-alloy steels characterized by a microstructure consisting of martensite and ferrite. Dual Phase steels combine high strength levels with good ductility. Thus, DP steels are potentially very attractive for the automobile industry. In addition to the required high strength and ductility, DP steel has to be cold formed into complex shapes. It appears that DP steel damage behaviour is very complex and cannot be predicted using existing models based on standard mechanical properties. This work is concerned with the study of microstructural evolution and investigation of the relation between the microstructure and damage mechanisms in a reference DP 780 steel. Two damage mechanisms have been identified in this DP steel: ferrite/martensite interface decohesion and void formation at tempered carbides. A simple modeling for qualitative description of the observed damage formation mechanisms is proposed. This modeling permits a basic understanding of the experimentally observed trends and could be used as the starting point for a more detailed analysis in future
Pu, Xiaoxue. "Thermomechanical study of the gigacycle fatigue behavior of pure iron and carbon-manganese steels : influence of chemical composition and microstructure on damage and crack initiation mechanism". Thesis, Paris 10, 2019. http://www.theses.fr/2019PA100051.
This work attempts to a better understanding of the fatigue damage in ferrite-pearlite steels in the Very High Cycle Fatigue (VHCF) domain. The influences of two parameters, pearlite phase percentage and free interstitial atoms percentage in solid solution, are investigated to understand dissipative mechanisms under 20 kHz high frequency fatigue loading. In-situ infrared thermography is carried out to record the temperature changes, while fractography studies and microscope observations are conducted to investigate the dissipative mechanism on the surface of specimens.For body centered cubic (BCC) materials, under high stress amplitudes, a sudden increase of the temperature occurs without a crack initiation and fracture. The inevitable temperature increase up to hundreds of degrees at high stress amplitudes, is caused mainly by the screw dislocations mobility, which is the key to explaining the observed fatigue behavior and thermal response of BCC structure under high frequency loading. Therefore, PSBs on surface and micro-voids in matrix emerge massively, accompanying with this abrupt temperature increase. These phenomena are considered as transition of deformation mechanism from thermal regime to athermal regime. At low amplitudes, few PSBs or surface roughness are still observed on the specimen surface. Through the cycles of PSB appearance on armco-iron, it’s found that PSBs are inclined to appear before 1x10(7)cycles, and PSB threshold lies below the conventional fatigue limit. The increase of pearlite phase content weakens the temperature elevation, and strengthens the fatigue properties. The presence of free interstitial atoms in steels results in appearence of a secondary temperature increase in the stabilized temperature part (100-200 degree). This behavior seems to be related to the interaction of edge dislocations with free interstitial atoms. Moreover, the remarkable hardening-softening-hardening phenomenon after the sudden temperature elevation to above 300 degree is thought as the interaction of multiplicated screw dislocations and free interstitial atoms
Gonzalez, Hermosilla Wilfrido Arturo. "Estudio del comportamiento en fatiga de un acero SAE 1045 recubierto con WC-10%Co-4%Cr depositado mediante proyección termica de alta velocidad". Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10121/document.
The present research work has been carried out in order to study the influence of the surface preparation of a SAE 1045 steel substrate on its fatigue behavior after coating with WC-10%Co-4%Cr deposited by HVOF thermal spraying. Prior to HVOF deposition, the substrate was prepared in three different surface roughness conditions, in order to provide mechanical bonding to the coating. The microstructural analysis of the coated systems was carried out employing SEM techniques. The substrate surface roughness was evaluated by means of optical perfilometry and the adherence of the coating to the substrate was studied employing interface indentation techniques. The elastic modulus of both substrate and coating was determined by means of ultrasound techniques. The fatigue behavior of the substrate-coating system was investigated under rotating bending conditions (R = - 1), employing maximum alternating stresses in the range of 358-420 MPa. A numerical simulation, employing a FEM commercial code, was carried out in order to describe the fatigue behavior of the coated systems. This investigation has allowed a better understanding of the fatigue behavior of the coated systems obtained by HVOF thermal spraying and the correlation of such a behavior with important parameters such substrate roughness, coating microstructural characteristics and its adherence to the substrate
Marchal, Arnault. "Comportement thermomécanique d'aciers déformés par essais de torsion à chaud". Vandoeuvre-les-Nancy, INPL, 1997. http://www.theses.fr/1997INPL013N.
Caisso, Camille. "Caractérisation et modélisation de la rupture dans le domaine de la transition ductile-fragile de matériaux tubulaires utilisés dans la fabrication de générateurs de gaz pour airbags". Thesis, Brest, École nationale supérieure de techniques avancées Bretagne, 2021. http://www.theses.fr/2021ENTA0014.
This work deals with the characterization of the ductile and brittle failure mechanisms of tubular materials used for the manufacture of airbag gas generators. During a crash, airbag cushion is inflated in a few milliseconds by a gas generator. In case of gas generator failure, a ductile failure mode must be ensured up to temperatures of -60°C. A Charpy ring test has been proposed to quantify the risk of brittle failure of gas generator materials. However, this modification of the Charpy test raises two issues: to what extent does this test allow to characterize the ductile-fragile transition and how can the risk of brittle failure of an operating gas generator be deduced from the results of the Charpy test? To answer these questions, an approach combining experiments and numerical simulations was implemented. Various experimental configurations were developed in order to characterize material behavior and ductile damage. The ductile failure is modeled with a local approach. Then, ductile to brittle transition was characterized by a Charpy ring test campaign performed for temperatures between -160°C and 23°C. A numerical study of this test was carried out. Coupled with the Charpy tests, it allowed to set up a model of the brittle failure. The risk of gas generators brittle failure is finally evaluated. The influence of the manufacturing process on the risk of brittle failure was also studied
Curtet, Émilien. "Évolution microstructurale et compréhension des mécanismes de déformation d'un acier austénitique stabilisé au titane pour les réacteurs de quatrième dimension". Thesis, Poitiers, 2019. http://www.theses.fr/2019POIT2293.
The fourth generation of nuclear reactors must meet new requirements for safety, energy efficiency, and integration into the nuclear fuel cycle. The CEA is a primary actor in this field and is developing new concepts for sodium-cooled fast reactors. The fuel cladding material being considered for these reactors is 15-15Ti AIM1 steel (Austenitic Improved Material #1), which is an advanced austenitic stainless steel containing 15-wt% chromium and 15-wt% nickel, Ti-stabilized and slightly cold-worked. This steel exhibits a singular loss of ductility between 20 and 200°C: the uniform and total elongations (UE and TE) are reduced by a factor of 3 in this temperature range. In addition, the effect of thermal aging on the microstructure and mechanical behavior is poorly known in the lowest operating conditions that are between 400 and 600°C. In this context, the objectives of this Ph.D. thesis are: - Increase our knowledge of the deformation mechanisms involved in the singular behavior at 200°C ; - Study the influence of a thermal aging between 400 and 600°C on the microstructural evolutions and on the mechanical behavior, with particular attention on the singularity at 200°C. Examining the relation between the singular behavior at 200°C and the related deformation mechanisms required a multi-scale approach combining techniques such as tensile tests, Electron Backscatter Diffraction (EBSD), and Transmission electron Microscopy (TEM). The analyses revealed: - A coexistence of twinning and perfect slip at 20°C;- An extinction of twinning replaced by a predominance of perfect slip associated with cross-slip at 200°C;- A continuous increase of the Stacking Fault Energy (SFE) from 20 to 200°C. In particular, the measured values are respectively 27 mJ/m² and 46 mJ/m². The evolution of the deformation mechanisms of 15-15Ti AIM can be explained by a competition between twinning and cross-slip for releasing the strain energy of the material. At 20°C, both dislocation glide and twinning are active, and the twinning produces a “Dynamic Hall-Petch Effect”, which produces continual strain hardening of the microstructure even at high strains, which leads to high ductility. On the other hand, the stacking fault energy is high at 200°C, so twinning no longer occurs, but cross-slip becomes active. Thus, little strain hardening occurs at 200°C, which leads to the rapid onset of strain localization and reduced ductility.Samples that were aged between 400 and 600°C for 1000 hours exhibit no evidence of material recovery. However, TEM observations established a new threshold for the precipitation of nanometric titanium carbides after an isothermal treatment at 500°C for 5000 hours. Concerning the tensile properties, the aged states present a gain both in strength (especially in Ultimate Tensile Strength) and in ductility (UE, TE) compared to the initial cold-worked state. This gain in ductility is observed for all of the temperatures tested (between 20 and 400°C) and is accompanied by an increase of the strain hardening rate of the material. One plausible hypothesis to explain this improvement of the mechanical behavior relies on the nanometric titanium carbides formed during the aging process. These precipitates could prevent by pinning the initially present dislocations to recombine or annihilate with the dislocations introduced by the tensile test
Mauchin, Agnès. "Comportement mécanique à haute température de composites carbone/carbone". Bordeaux 1, 1997. http://www.theses.fr/1997BOR10676.
Wang, Zhao. "Propriétés Electro-mécaniques des Nanotubes de Carbone". Phd thesis, Université de Franche-Comté, 2008. http://tel.archives-ouvertes.fr/tel-00352725.
Nous modélisons ensuite, de façon atomistique, la distribution surfacique de charge électrique sur des nanotubes de carbone possédant une charge nette. Nous retrouvons notamment l'effet de pointe classique avec un très bon accord quantitatif avec des résultats expérimentaux obtenus par microscopie à force électrostatique.
Par combinaison des méthodes utilisées dans les études précédentes, nous simulons la déflection de nanotubes semi-conducteurs et métalliques par un champ électrique extérieur, dans une configuration de type interrupteur moléculaire. L'effet des caractéristiques géométriques des tubes et du champ sur cette déflection ont été systématiquement étudiés.
En outre, nous avons vu que des simulations de dynamique moléculaire avec le potentiel AIREBO permettent de retrouver quantitativement les énergies expérimentales d'adsorption du benzène, du naphtalène et d'anthracène sur le graphite. Ce type de simulation nous permet d'avancer sur la voie de la compréhension de la sélectivité de l'adsorption de certaines molécules surfactantes à plusieurs cycles benzéniques sur des nanotubes de chiralité donnée.
Wang, Zhao. "Propriétés électro-mécaniques des nanotubes de carbone". Besançon, 2008. http://www.theses.fr/2008BESA2066.
This thesis aimed at modeling the mechanical behavior of carbon nanotubes (CNTs) in electric fields. We first used molecular dynamics (MD) simulations with the AIREBO potential to study the non- linear elasticity and the torsion strength of CNTs as a function of their length, radius and helicity. We find for example, that the effective Young's modulus of a CNT decreases with a steeper slope for smaller helicities. Also, the ultimate value of the deformation energy that can be stored in CNTs is found to increase with smaller radii. Then, we modeled the distribution of electric charges on carbon nanotubes carrying a net charge. An atomic charge-dipole model regularized by convolution with a Gaussian is used. Extrapolation of our theoretical results agree quantitatively with experimental results from electrostatic force microscopy experiments. We also combined the methods used in both previous parts to simulate the deformation of nanotubes in electric fields. We demonstrate the influence of the external field, the geometry of the tube and the property of electronic transport of the tube on the electrostatic deformation. Finally, we checked that MD simulations with the AIREBO potential agree quantitatively with experiment results for the absorption of benzene, naphthalene or anthracene on graphite. We then studied the physisorption of surfactants with several benzene rings on CNTs in order to assess their efficiency for the select ion of CNTs according to their diameter or chirality
Suarez, Fernandez Maribel. "Estudio del comportamiento ante la corrosión y desgaste de recubrimientos obtenidos por proyección térmica". Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10120/document.
The present work has been devoted to the study of the corrosion and wear behaviors of CrNi-9.5%C coatings deposited onto a SAE 1010 steel substrate by a vacuum plasma thermal spray process. The studies were carried out with the coatings both in the as-deposited condition and after heat treatment in argon, at temperatures varying between 600° to 900oC. It has been found that the coatings contained mainly Cr3C2 and NiCr, irrespective to the heat treatment temperature. It has been shown that the response of the coated systems during the potentio-dynamic tests in a 3.5% NaCl solution depends strongly, besides the coating thickness, on the microstructural coating evolution that occurs during heat treatment. It has been found that the heat treatment performed at 900oC, for the 450 mm coating thickness, allowed the reduction of approximately 97% of the corrosion current density, as a result of a solid-state diffusion phenomenon, which produced a higher lamellar cohesion, impeding the penetration of the corrosive solution. The main corrosion mechanism has been attributed to the galvanic corrosion phenomenon, as a consequence of the remarkable difference between the electrochemical properties of the matrix and those of the existing carbides in the coating. During the sliding tests, the coated systems rubbed against alumina under a 5 N normal load, indicated a progressive change in the mechanism, from a mixed adhesive and abrasive, to a predominant abrasive as the heat treatment temperature increases. However, the wear constants were found to be of the order of approximately of 10-6 mm3/N.m, indicating that a satisfactory behavior from the tribological point of view
En el presente trabajo se estudio el comportamiento ante la corrosión y el desgaste de recubrimientos de CrNi9,5%C depositados sobre un acero SAE 1010 usando la técnica de proyección térmica de plasma al vacío (VPS). Los estudios se realizaron para los recubrimientos tanto en condición de cómo depositados como tratados térmicamente, en atmósfera de argón, a temperaturas de recocido de 600°, 800° y 900°C. Se encontró que el recubrimiento tiene Cr3C2 y NiCr como fases mayoritarias, independiente de la temperatura del tratamiento. La respuesta de los sistemas recubiertos durante los ensayos potencio-dinamicos en solución acuosa de 3.5% NaCl indicó una significativa dependencia tanto del espesor, como de los cambios microestructurales producidos en función de la temperatura de tratamiento térmico. Se determinó que el tratamiento térmico realizado a 900oC, para un recubrimiento de 450mm de espesor, ha permitido una reducción de aproximadamente un 97% del valor de la densidad de corriente, como resultado del aumento en la cohesión interlamelar obtenida debido al fenómeno de difusión en estado sólido, lo cual impide la penetración de la solución agresiva. En este caso, el mecanismo principal de daño se debe al proceso de corrosión galvánica, como consecuencia a la diferencia apreciable existente entre la naturaleza electroquímica de la matriz de Ni con respecto a los carburos. La respuesta del sistema recubierto contra alumina durante los ensayos de desgaste deslizante bajo 5N de carga normal indica que tiene lugar un cambio progresivo del mecanismo combinado de desgaste adhesivo y abrasivo hacia un mecanismo mayormente abrasivo, a medida que la temperatura del tratamiento termico aumenta. Sin embargo, las constantes de desgaste determinadas para todos los ensayos llevados a cabo se encontraron del orden de 10-6 mm3/N.m, indicando un comportamiento satisfactorio desde el punto de vista tribologico
Souyris, Vincent. "Structures et propriétés mécaniques des soudures multipasses en acier austénitique inoxydable". Montpellier 2, 1990. http://www.theses.fr/1990MON20143.
Cliche, Nicolas. "Recristallisation et propriétés mécaniques d'un acier inoxydable austénitique stabilisé au niobium". Paris, ENMP, 2019. http://www.theses.fr/2019PSLEM070.
The 316Nb steel is a niobium-stabilized austenitic stainless steel with an outstanding yield stress and an outstanding corrosion resistance, even at elevated temperatures. It is used in components made by hot open-die forging. Due to two different remelting processes, two different grades have been studied : an ESR (electro-slag remelting) reference grade and a VAR (vacuum arc remelting) grade with notably less nitrogen. In order to harden this steel, we want to hinder recrystallization during forging and subsequent annealing. Therefore, we studied the dynamic, post-dynamic and static recrystallizations of this steel. We found that dynamic recrystallization was very limited for this steel in the usual forging conditions. If very large strains are applied, dynamic recrystallization progresses mainly in a continuous way by grain fragmentation. The main phenomena concerning post-dynamic and static recrystallizations strongly depend on the initial state of the microstructure (called preconditioning) through especially the niobium, the carbon and the nitrogen contents in solid solution in the austenite matrix. These contents vary a lot with the thermal history of the forging process. A diffusion model based on thermokinetic simulations has been adapted to the different grades. For a given preconditioning, torsion tests and EBSD (electron backscatter diffraction) maps showed that the recrystallization kinetics of the two grades were very close. We also found, by comparison between torsion, uniaxial compression and channel-die compression tests, that the deformation mode did not have significant effects on post-dynamic and static recrystallizations. We built a model of microstructural evolutions which did not depend on the deformation mode. We adapted and further developed a mean-field recrystallization and grain growth model based on dislocation densities and grain size distributions. Its advantages and limits along with its application to a heterogeneous structure (a forged block) are presented. Finally, we studied in depth the influence of the microstructure on the mechanical properties of the two grades thanks to sequenced torsion and traction experiments and tensile tests on forged blocks. Thus, quantitative correlations between the microstructure and the mechanical properties have been established
Dehoux, Anita. "Propriétés mécaniques des couches de produits de corrosion à l'interface acier / béton". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2012. http://tel.archives-ouvertes.fr/tel-00828155.
Caramaro, Laurence. "Cristallisation du polysulfure de phénylène en présence de fibres de carbone : application à des composites unidirectionnels PPS-carbone". Lyon 1, 1990. http://www.theses.fr/1990LYO10184.
Martin, Marie-Hélène. "Caractérisation des interfaces acier-fonte-carbone de l'ensemble anodique d'une cuve d'aluminium". Thesis, Université Laval, 2014. http://www.theses.ulaval.ca/2014/30645/30645.pdf.
The aluminum industry faces economical headwinds, thus needing to reduce its operating costs. The project studies specifically energy losses at anode sealing location. Experiments were conducted from room conditions up to the maximum capacity of the bench test. Laboratory work was completed using tri-material samples (made in such a way to replicate accurately reality) and an innovative bench test using magnetic induction as a source of heat that enables minimal heat-up time and sample oxidation during experiments. Non-linear regression was then used to retrieve a model from laboratory results. Analysis showed that a power model represents accurately the interfaces behavior from room to operation conditions. Comparison with literature showed that the order of magnitude is the same but results are not similar. This observation can be explained by the use of slightly different materials and also due to the use of a different experimental procedure.
Deurbergue, Arnaud. "Fibres de carbone ex-polyacrylonitrile : stabilisation, carbonisation, relations avec les propriétés mécaniques". Pau, 1989. http://www.theses.fr/1989PAUU3012.
Dumont, Mikaël. "Composites Carbone/Carbone 3D densifiés par imprégnation/carbonisation de brai mésophasique". Bordeaux 1, 2001. http://www.theses.fr/2001BOR12344.
Jacques, Pascal. "On the physics and mechanics of phase transformations in TRIP-assisted multiphase steels". Université catholique de Louvain, 1999. http://edoc.bib.ucl.ac.be:81/ETD-db/collection/available/BelnUcetd-10152008-112555/.
Galtier, André. "Contribution à l'étude de l'endommagement des aciers sous sollicitations uni ou multi-axiales". Paris, ENSAM, 1993. http://www.theses.fr/1993ENAM0008.
Da, Silva Craidy Pedro. "Interactions Hydrogène-Microstructure-Propriétés Mécaniques dans les Composants en Acier Inoxydable Super Suplex". Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAI041.
The increasing demand for energy requires the exploration of oil and gas at deeper water locations and on more severe conditions. These production systems have demanded the use of forged equipments made of higher strength steel grades, such as austenitic-ferritic (duplex) stainless steels. These components are more prone to exhibit loss of ductility and general mechanical performance caused by hydrogen generated e.g. by cathodic protection. Duplex stainless stainless steels components present a vast history of hydrogen damage at low temperatures, due to hydrogen derived from various sources. Even being this kind of damage fairly recurring, various related information remains to be elucidated, due to the complex interaction of hydrogen with the microstructure and localized character of hydrogen generation and transportation in the material. The present work aims to improve the physical understanding of the interaction between hydrogen and the microstructure as well as the effects of different hydrogen charging procedures on the mechanical properties of forged components made of the super duplex stainless steel grade UNS S32750.The development of such understanding involves the evaluation of the effects of hydrogen on the mechanical properties of the material through tensile tests in different hydrogen-rich environments. Based on results of slow-strain rate tensile tests, a quantitative relationship between embrittlement caused by gas hydrogen and cathodic charging is proposed, and possible effects of dislocation-assisted hydrogen transportation and embrittlement are discussed. Quantitative and qualitative descriptions of the hydrogen transportation, including analysis of the effects of different microstructures and diffusion paths, and of its position in the lattice and in the microstructure (hydrogen segregation to traps) are proposed. These descriptions are achieved considering results of different testing techniques: permeation tests, thermal desorption spectroscopy, time-of-flight secondary ion mass spectroscopy and neutron scattering
JEUNEHOMME, Sylvie. "Relations propriétés mécaniques - microstructure des aciers de structure perlitique". Paris, ENMP, 1991. http://www.theses.fr/1991ENMP0320.
Depradeux, Lionel. "Simulation numérique du soudage - Acier 316L : validation sur cas tests de complexité croissante". Lyon, INSA, 2004. http://theses.insa-lyon.fr/publication/2004ISAL0014/these.pdf.
The aim of this study is the prediction with numerical simulation of residual stresses and distortions generated by the welding process. The special case of the TIG welding process on 316L steel is considered. In order to investigate phenomena and difficulties that must be taken into account for the numerical simulation of the welding process, a parallel experimental and numerical study is carried out on different kind of tests, of increasing complexity, from one dimensional to three-dimensional. As first step, one-dimensional tests are led on round bar specimen for which temperatures and stresses are macroscopically homogeneous in the studied zone. These tests investigate the thermo-mechanical behavior of the steel, when submitted to thermal cycles similar to those that occur in the Heat Affected Zone during welding. This kind of test is also very useful for the validation of different constitutive equations. As second step, axi-symmetrical tests are led on simplified structures in order to investigate the structure effect and problems due to the presence of a weld pool. Lastly, a test more representative of a real welding operation, which involves a moving heat source, integrates the three-dimensional effect. In parallel, numerical simulations are performed for each test, using the finite element code code_Aster (EDF). Comparative analysis between experimental and numerical results allows the assessment of the ability of the numerical code to predict residual stresses and distortions, and parametric analysis allow us to investigate the sensitivity of numerical results to material characteristic data, constitutive equation, or modeling of the heat input
Shigesato, Genichi. "Développement de structures de dislocations dans les aciers : relation avec les propriétés mécaniques". Grenoble INPG, 2007. http://www.theses.fr/2007INPG0102.
The mechanical behaviour and the evolution of the dislocation substructure of 1. 5% Cu added ferritic steels with various aging time are investigated after shear deformation. The aged materials are hardened by sm ail copper precipitates «1 Onm). The hardening behaviours for precipitate sizes ranging from 1 to 10 nm are analysed. Transmission electron microscopy observation show that the dislocation microstructure is not uniquely related to the strain rate or the level of the cumulated strain. This indicates that the patterning is promoted by the dislocation mutual interactions and delayed with the applied stress level. The evolution of the local misorientations measured by automatic orientation indexing procedure shows also that they are not correlated with the dislocation substructure aspect. Finally, a numerical modelling based on 3D discrete dislocation dynamics is developped in order to compute the effect of the precipitate distance on the dislocation annihilation rate
Amara, Dehman. "Assemblage structural collé alumine-acier 304L : propriétés superficielles des substrats et adhérence". Toulouse, INPT, 1993. http://www.theses.fr/1993INPT005G.
Soler, Michel. "Etude du vieillissement d'un acier a Bake-Hardening : évolution des propriétés mécaniques de traction - correlation avec la microstructure". Lyon, INSA, 1998. http://www.theses.fr/1998ISAL0074.
Bake-Hardening steels allow automobile constructors to benefit of a comprise of good formability and of high indentation resistance. . Indeed these steels have low yield stress and have the capability to increase it by about 20 % after stamping, by paint-baking treatment. The aim if this. Work is to study the microstructural mechanisms witch take place during strain-aging and their consequences on mechanical properties. To reach these objectives, we have studied the Lüders band deformation mode characterized the microstructure before and after aging. Lots of macroscopical and microscopical techniques have been used to characterize the material. The Lüders band deformation mode shows that their~ plastification stress (σD relative to point D) , after aging, is non accessible experimentally and that the only physical point Witch is accessible and related to D by a local behavior low is the point H, representative of the homogeneous plastification beginning. From H we define a relative hardening parameter noted BH*witch origin is the pre deformed state and unaged. We follow H and BH* evolution for all the thermo mechanical treatments done More over, we study the microstructural evolution during aging. Finally we give an interpretation of the age microstructure effects on the local behavior low which allow us to exp lain the H and BH* evolutions observed during the same time
Gardiola, Bruno. "Etude de propriétés mécaniques d'aciers HSLA obtenus par CSP, en relation avec les textures, microstructures et changements de phase". Metz, 2002. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/2002/Gardiola.Bruno.SMZ0217.pdf.
Bouanis, Fatima Zahra. "Amélioration des propriétés anticorrosion d’un acier au carbone par nitruration par plasma froid radiofréquence". Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10183.
The aim of this work concerns the study of the improvement of the corrosion resistance in acidic medium (1M HCl) and mechanical properties of carbon steel (XC38) using a radiofrequency cold plasma nitriding process. The originality of this work consists in nitriding substrates using nitrogen cold plasma, where the process temperature is roughly ambient temperature and without heating the substrate. The nitriding was carried using nitrogen and nitrogen/ hydrogen plasma gas mixtures. The hydrogen role in the plasma consists not only in reducing the iron oxide layer on the substrate, but also accelerates the nitrogen diffusion in the substrate. Surface characterizations performed by means of the Electron Probe Microanalysis (EPMA) and X-ray Photoelectron spectroscopy (XPS) indicate that the treatment plasma induces the formation of a layer where the nitrided thickness is higher than ten microns for long treatment times (8h). The mechanical properties were studied by Vickers microhardness. The surface microhardness of the nitrided steel increases as the plasma processing time increases to reach a maximum of 1057Hv0.005 for the nitrided sample that was treated during 8h, when compared to sample untreated (247Hv0.005). The improvement of the corrosion resistance properties were investigated by gravimetric and electrochemical techniques such as potentiodynamic polarisation curves and electrochemical impedance spectroscopy (EIS) in 1M HCl medium. For the optimal conditions of treatment, the inhibition efficiency obtained is more than 95 % for 8h of treatment and remains constant for immersion times higher than 72h in aggressive medium (HCl 1M)
Komla, Adéchion. "Etude de la texture de couches à propriétés optiques et catalytiques spécifiques obtenues à partir d'aciers inoxydables". Toulouse 3, 1991. http://www.theses.fr/1991TOU30277.
Coran, Aubert Y. "La dispersion du noir de carbone dans le caoutchouc". Mulhouse, 1992. http://www.theses.fr/1992MULH0258.
Pailhes, Jérôme. "Comportement mécanique sous sollicitations multi-axiales d'un composite carbone-carbone". Bordeaux 1, 1999. http://www.theses.fr/1999BOR12152.
Pailhes, Jérôme. "Comportement mécanique sous sollicitations multi-axiales d'un composite carbone-carbone". Bordeaux 1, 1999. http://www.theses.fr/1999BOR10667.
Guilhem, Yoann. "Étude numérique des champs mécaniques locaux dans les agrégats polycristallins d'acier 316L sous chargement de fatigue". Phd thesis, Paris, ENMP, 2011. http://www.theses.fr/2011ENMP0108.
Cyclic thermomechanical loadings lead to the formation of short fatigue cracks, the initiation phase of which is prominent over the total life of the component. Mechanisms related to the evolution of these cracks have a high dependence on the microstructure of the material, especially under low-amplitude loading. To study this dependence, a statistical study based on the results of finite element calculations of polycrystalline aggregates was conducted. First, the problem was treated in two dimensions, with a simplified crystal plasticity model. Analysis of the results allowed to highlight the neighboring effect in polycrystals and to reproduce the dispersion of fatigue results observed at the surface. Using a three-dimensional model and investigating different loadings, it was possible to correlate the localization structures of plastic deformation in the volume of the aggregate with the experimental observations. Also, the steps of surface intrusions and extrusions induced by fatigue loadings, preferential sites of initiation, have been reproduced and highlight the harmful effects of biaxial loadings. The problem of effects was raised, reducing the results sample that can be used by a statistical treatment. Second, the introduction of surface roughness in the simulated aggregates highlighted the competition between the microstructural parameters and geometric singularities of the free surface. This analysis has shown that there must exist a limiting surface state, from which the effect of the roughness takes over the crystallographic aspect concerning the plastic deformation localization at the surface of polycrystals. However, this effect fades quickly when depth increases and becomes almost nil under the first layer of surface grains. Finally, another three-dimensional model, both periodic and accounting for the free surface effect, called semi-periodic model has been implemented to eliminate boundary condition effects and to fully exploit the results of calculations. This method also brings new perspectives for the development of a new mean fields model dedicated to the behavior of surface of polycrystals
Guilhem, Yoann. "Étude numérique des champs mécaniques locaux dans les agrégats polycristallins d'acier 316L sous chargement de fatigue". Phd thesis, École Nationale Supérieure des Mines de Paris, 2011. http://pastel.archives-ouvertes.fr/pastel-00732147.
Juanicotena, Antoine. "Etude théorique et expérimentale du comportement viscoplastique des matériaux aux grandes déformations et grandes vitesses de déformation : application à l'acier Mars 190 et au tantale". Metz, 1998. http://www.theses.fr/1998METZ024S.
Probst, Nicolaus. "Etude des propriétés électriques et diélectriques des composites polymères - noirs de carbone : parallélisme entre propriétés électriques et mécaniques". Mulhouse, 1991. http://www.theses.fr/1991MULH0180.
Naser, Hasan. "Développement de micro-composites architecturés en aciers inoxydables duplex : élaboration, microstructure et propriétés mécaniques". Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAI024/document.
The use of duplex stainless steel (DSS) grades for structural applications is considered as one of the most significant advances impacting the construction sector. This is because of their high mechanical properties coupled with interesting functional properties such as corrosion resistance or even the low thermal conductivity compared to carbon steels. Due to their complex microstructure and interaction between the phases, DSS have a significant potential for unique properties. A better understanding is needed to give the possibility to obtain break through properties and to provide the possibility to design tailor-made, architectured DSS for specific applications. In this work we proposed a different approach from that used until now to understand the behavior of DSS. The strategy adopted in this work was a top-down strategy in which at least two bulk metals with well known behavior and properties are mechanically alloyed by Severe Plastic Deformation (SPD). This proposed strategy served two main objectives: i) enhancing the properties by microstructure refining down to sub-micron scale ii) elaborating a material model for understanding the DSS behavior obtained by the conventional metallurgical methods. The first objective of this work was, therefore, the implementation of a methodology of manufacturing using SPD technique by co-drawing. This technique will allow obtaining an ultra-fine microstructure of 316L/430LNb composites. One of the challenges met during our study was the significant inter-diffusion during heat-treatment step necessary during processing preventing by consequence further refining. An optimization investigation was carried out to account the role of this inter-diffusion for 316L/430LNb couple. Multi-scale micro-composites have been then obtained. In this work, we showed the limitation of this process in terms of microstructure refining. A rationalization of these limits was given by studying the thermo-kinetics of both micro-composites and bulk materials. In parallel with the microstructural evaluation, the mechanical behavior of these new micr-composites was examined. In order to provide a more in-depth explanation of the plastic behavior of our composites, in situ tensile test using high energy X-ray synchrotron have been performed
Mabille, Pascal. "Évaluation des hétérogénéités locales de déformation d'aciers extra-doux sollicités en traction et en fatigue". Toulouse, ENSAE, 1995. http://www.theses.fr/1995ESAE0005.
Mebarki, Nadia. "Relation microstructure-propriétés mécaniques d'aciers martensitiques revenus destinés aux outillages de mise en forme d'alliage légers". Paris, ENMP, 2003. http://www.theses.fr/2003ENMP1124.
Valance, Stéphane. "Aspects mécaniques du changement de phase allotropique à l'échelle mésoscopique". Lyon, INSA, 2007. http://theses.insa-lyon.fr/publication/2007ISAL0101/these.pdf.
The prediction of the mechanical state of steel structures submit to thermo-mechanical loading must take into account consequences of allotropic phase change. Indeed, phase change induce, at least for steels, a mechanism of TRansformation Induced Plasticity (TRIP) leading to irreversible deformation even for loading less than elastic yield limit. Homogeneized analytical models generally fail to achieve a correct prediction for complex loading. In order to overcome these difficulties, we present a model achieving a sharper description of the phenomenon. The mesoscopic working scale we adopt here is the grain scale size. Hence, we consider that the behaviour of each phase is homogenous in the sense of continuous media mechanic, whereas the front is explicitly described. We work both experimentally and numerically. Experimentally, we designed a test facility enabling thermo mechanical loading of the sample under partial vacuum. Acquisition of sample surface while martensitic transformation is happening leads, under some hypothesis and thanks to Digital Image Correlation, to the partial identification of area affected by transformation. Numerically, the eXtended Finite ElementMethod is applied for weakly discontinuous displacement fields. Used of this method needs to numerically track the transformation front -discontinuity support. In that goal, based on level set method, we develop FEM numerical scheme enabling recognition and propagation of discontinuity support. Finally, this work is complete by an approach of driving forces introduced through Eshelbian mechanics which are dual of front velocity. Keywords : allotropic phase change, TRansformation Induced Plasticity, eXtended Finite Element Method (X-FEM), Level set method