Gotowa bibliografia na temat „Défauts de solidification”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Spis treści
Zobacz listy aktualnych artykułów, książek, rozpraw, streszczeń i innych źródeł naukowych na temat „Défauts de solidification”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Artykuły w czasopismach na temat "Défauts de solidification"
Nadif, M., A. Solimine, P. Ominetti, P. Velluet, M. Blandel i M. Roscini. "Influence de la solidification de la première peau sur la génération des défauts sur brame. Utilisation de l'oscillation hydraulique à Sollac Florange". Revue de Métallurgie 89, nr 10 (październik 1992): 847–56. http://dx.doi.org/10.1051/metal/199289100847.
Pełny tekst źródłaRozprawy doktorskie na temat "Défauts de solidification"
Lantreibecq, Arthur. "Détermination de la nature et de l'origine des défauts cristallins dans le silicium monolike". Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30311/document.
Pełny tekst źródłaMonolike silicon (ML Si), is a material obtained by directional solidification on monocrystalline seeds and dedicated to photovoltaic applications. This thesis focuses on the structural quality of these crystals of several hundred kilograms that contain defects that potentially affect the photoelectric yield. The goal is to understand the mechanisms by which these defects nucleate and multiply in order to inhibit them. Since the development of sub-grain boundaries (SGB), which are the main factors for the losses of photovoltaic yields, is potentially related to the thermomechanical stresses that develop during a thermal cycle, we simulated numerically the temperatures of an oven containing an ingot over a complete cycle (fusion, growth, cooling). From the temperature values, we were able to establish a map of the thermomechanical stresses as well as their temporal evolution. In parallel, we used several structural and electrical characterization techniques to analyze crystalline defects and their distribution in the ingot at different scales. During the cycle, a first maximum of stress at the end of the heating stage generates dislocations and precursors of SGB in the seed. The second stress maximum at the end of solidification / start of cooling stage leads to the final organization of background dislocations present in the whole ingot. Once the SGB appear, they extend laterally as the solid-liquid interface progresses. These SGB have a structure consisting of sessile and vertical dislocations, which follow the solidification front and also mobile dislocations that interact with this pre-existing structure. The integration of these mobile dislocations, which can occur just below the solid-liquid interface or during cooling, increases the misorientation of the SGB. [...]
Banos, Julien. "Modélisation du procédé de refusion à l’arc sous vide : Échanges thermiques et défauts de solidification". Electronic Thesis or Diss., Université de Lorraine, 2023. http://www.theses.fr/2023LORR0117.
Pełny tekst źródłaThe Vacuum Arc Remelting (VAR) process is used in the production of high-added value metals such as titanium alloys or nickel-based superalloys for the aerospace industry. The control of solidification conditions is an important industrial issue in order to process ingots of adequate chemical homogeneity and free of solidification defects. The work presented in this manuscript aims at improving the description of heat exchanges in a VAR process model (SOLAR) and at proposing a new approach for the prediction of segregated channels type solidification defects. First, the description of the heat exchanges in the model between the electrode, the ingot, the mould and the cooling circuit has been improved. These modifications were validated by comparing the numerical results with measurements from real industrial melts. An original experimental apparatus for measuring the external mould temperature adapted to industrial melts was designed. This apparatus was used during an experimental campaign on an industrial site during the remelting of a titanium alloy. The measurements obtained were compared with the numerical results from SOLAR. These two activities led to a first implementation of the side-arcing phenomenon in the model. In parallel, a multi-scale numerical approach was developed to predict the formation of segregated channels as a function of local solidification conditions. A first study on a Sn-Pb alloy was carried out and a mathematical criterion was calculated from the results. This first study shows a much lower impact of the thermal gradient on the formation of segregated channels than that generally considered in the literature
Boubeker, Rabia. "La formation des structures équiaxes : mouvement des grains, croissance-refusion, conséquences sur les macroségrégations". Vandoeuvre-les-Nancy, INPL, 2004. http://docnum.univ-lorraine.fr/public/INPL_T_2004_BOUBEKER_R.pdf.
Pełny tekst źródłaIn order to improve the predictions ofheterogeneitiesof composition observed on steel ingots at the end of solidification, a numerical study which takes into account the movement and the growth of equiaxed grains has been realized. After a bibliographic part related to the formation of the equiaxed grains, a diphasic approach has been adopted to describe the growth and the remelting of globular grains moving in the liquid bulk. This numerical study was implemented in the computer code SOLill. The movement of the grains has been described in a first part with the assumption that the grains move at the same speed than that of the liquid phase. The results obtained. " showed the influence of the movement and growth-remelting of the grains on solidification, especially in the evolution of the superheated zones. Then, we have taken into account the own movement of the grains which differs from that of the liquid phase. Ln this case, a solid fraction of coherence beyond which grains are imposed to be fixed has been introduced. This study showed that the final macrosegregation is strongly dependent on this fraction of coherency and on the flux density of fragments. Finally, we have demonstrated that it was possible to adjust the input data of the model in order to get a good agreement between the numerical and the experimental results
Winiar, Lionel. "Contribution à l'étude de la défectologie associée à la solidification des aciers". Valenciennes, 2003. http://ged.univ-valenciennes.fr/nuxeo/site/esupversions/4555ff1c-eb17-4bb0-a174-a9dce6d6d3f5.
Pełny tekst źródłaNew generation of steel casting processes allow to increase the production rate but they cause some imperfections instance. In this context, it is necessary to design some thermo-mechanical tests dedicate to studies the products defectology. The aim of this thesis is to optimize a thermo-mechanical test dedicate to the study of a hot brittleness of steels. The analyses main allow to generate objectives thermo-mechanical stresses of the strand casting product and know the parameters sensibility on the failure instance. Scientific contributions are relative to the hot ductility and micro or macro-segregation bonds and effects of strain during solidification on the cracks instances
Castro, Roman Manuel de Jesús. "Étude expérimentale et modélisation de la solidification des pièces coulées en fonte à graphite spheroidal : influence de la vitesse de refroidissement et de l'inoculation". Vandoeuvre-les-Nancy, INPL, 1991. http://docnum.univ-lorraine.fr/public/INPL_T_1991_CASTRO_ROMAN_M_J.pdf.
Pełny tekst źródłaGirard, Karen. "Etude de la création de défauts volumiques générés pendant la solidification de soudures réalisées par faisceau laser Nd : YAG impulsionnel - application au soudage du tantale". Dijon, 1999. http://www.theses.fr/1999DIJOS067.
Pełny tekst źródłaQuatravaux, Thibault. "Évolution de la modélisation du procédé VAR : contribution à la description de la dispersion inclusionnaire dans le puits liquide et à la prévention de défauts de solidification". Vandoeuvre-les-Nancy, INPL, 2004. http://www.theses.fr/2004INPL037N.
Pełny tekst źródłaThis thesis deals with the modelling of Vacuum Arc Remelting process (VAR) using the numerical software SOLAR. The first aim of the study is a better description of several physical phenomena which occur during melting, in order to extend the application of the software to simulate the remelting of steel. The evolution in the modelling of transport phenomena in the secondary ingot is based on three major improvements: - lateral thermal transfer modelling, in order to take into account the formation of a gap between the ingot and the mould walls, a possible injection of a neutral gas, and the heating of water in the coolant circuit, according to its flow, - a better turbulence model, since the k-E model implemented previously in the numerical code was not accurate enough to correctly descri~ the flow of the liquid metal in the pool, - a new method to simulate the ingot growth, based on a cyclic operation of splitting and growth/migration of control volumes, which reproduces the continuous growth of the secondary ingot and allows for the refinement of the mesh close to the free surface. Finally, the improved model has been validated by comparison with experimental results provided from four remeltings carried out on full-scale furnaces. The second objective is the characterization of the quality of the manufactured products in terms of inclusion cleanliness and risk of freckles segregated channel generation. Ln order to describe the behaviour of inclusions in the liquid pool, a trajectory model, adapted to account for turbulent flows, was validated and then implemented in the code. Various particle behaviours were distinguished. A study on the risk of freckles generation led to the establishment of a criterion particularly weIl adapted to the process. A generalization of this criterion, suggested in this work, would allow the prediction of the probable orientation of such segregated channels
Ouaddah, Hadjer. "Study of crystalline defects issued from silicon solidification : effect of impurities and correlation between crystallography, physicochemical and electrical properties". Electronic Thesis or Diss., Aix-Marseille, 2021. http://theses.univ-amu.fr.lama.univ-amu.fr/211214_OUADDAH_370ltw379yep573fxydon897z_TH.pdf.
Pełny tekst źródłaAn experimental approach including several techniques was used to characterize structural defects issued from the solidification by in situ X-ray imaging during solidification and by complementary ex situ techniques to characterize and quantify the grain structure, crystalline quality, and deformation. The composition and segregation of impurities were measured in correlation with the defect characterization and correlated to minority carrier lifetime measurements. The analysis shows significant influence of light impurities and metallic impurities on Si solidification and on the electrical properties. In the presence of light impurities, a higher frequency of grain nucleation is observed, it is linked to the presence of precipitates. The resulting grain structure is constituted by a higher proportion of high order twin and of random angle grain boundaries compared to the case of low contaminated samples. Moreover, local deformations are induced by the presence of SiC and are at the origin of SABGs (small angle grain boundaries) formation. The electrical properties are degraded (lower and inhomogeneous minority carrier lifetime) in the presence of light impurities compared to the case of pure Si materials. In Cu contaminated samples, no significant effect on the grain structure was evidenced. However, coherent Σ3 twin boundaries, which are defects of high crystalline quality, can be active in presence of Cu. This observation was correlated to Cu segregation at the level of these grain boundaries. During this study, recent progress concerning the in situ characterization of the defect formation dynamics during solidification allowed to open new prospects
Carpentier, David. "Modélisation de la formation des microporosités lors de la solidification d'alliages à base d'aluminium". Vandoeuvre-les-Nancy, INPL, 1994. http://www.theses.fr/1994INPL125N.
Pełny tekst źródła