Dissertations / Theses: 'TIB'

1

Svendsen, Lena. "On the processing of aluminium-C/TiC/TiB₂ composites /." Stockholm, 1998. http://www.lib.kth.se/abs98/sven0123.pdf.

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2

Sundararm, Venkatesh. "Reaction paths in the thermite syntheses of TiB₂ and TiB₂-Al₂O₃." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/18935.

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3

Lahres, M. [Verfasser]. "Mehrphasige TiC/TiB₂-Hartstoffschichten. Herstellung, Konstitution, Eigenschaften und Anwendungsverhalten / M. Lahres." Karlsruhe : KIT-Bibliothek, 1991. http://d-nb.info/1156327768/34.

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4

Wang, Kang. "Pressureless sintering and mechanical properties of TiN-TiB¦2 particulate ceramic composites." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2002. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ65652.pdf.

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5

Zhao, Fei. "Study on mechanical properties of the in situ TiB/TiC reinforced titanium matrix composites." Troyes, 2010. http://www.theses.fr/2010TROY0030.

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Ces travaux de recherche ont pour objectif d’étudier les effets des renforts TiB et TiC dans les composites à matrice de titane sur les propriétés mécaniques, par analyse et caractérisation expérimentale et simulation numérique. Le comportement de traction, de frottement et de fatigue d'une série de composites renforcés par in situ TiB/TiC a été mis en évidence. La méthode des éléments finis permet également de simuler les effets des renforts. Les résultats obtenus montrent que les TiB/TiC peuvent jouer un rôle important de renforcement lors de sollicitations complexes. Les propriétés des composites (module élastique et de cisaillement) et la rigidité de ces matériaux dépendent du type, de la quantité, de la forme et de la distribution des renforts. Les renforts peuvent empêcher la propagation des fissures dans le cas statique. En dynamique, les renforts TiB réduisent la résistance à la fatigue des composites lorsque la sollicitation est importante, mais peuvent augmenter cette résistance lorsque la sollicitation est faible; par contre les renforts de TiC peuvent améliorer la résistance à la fatigue des composites. Dans la pratique, il faut aussi tenir compte des conditions de mise en forme et d’application des composites. Le contenu des renforts devrait être déterminé en tenant compte du coût de fabrication, de sorte que nous puissions optimiser les besoins d’application réelle, mais également de réduire les coûts
The aim of this research is to study the effects of reinforcements TiB and TiC materials by experimental analyzing structures and mechanical testing of properties of in situ synthesize TiB/TiC reinforced titanium matrix composites. The tensile, friction and fatigue properties of in situ TiB/TiC reinforced composites structures were tested. Finite element analysis was also used to simulate the effect of the reinforcements. The results show that the reinforcements can play an important role in the composites properties. The elastic modulus and shear modulus have some relation with the type, the quantity, the shape and the distribution of the reinforcements in the composite materials. Some formulas about the modulus of the composites are suggested by modelling the composite behaviours with numerical method. The reinforcements can prevent the crack initiation and propagation in static load. For the fatigue properties, the reinforcement TiB reduces the fatigue life of the composites under high level of load, but increases it in low load conditions, while TiC reinforcements can improve the fatigue strength of the composites. So in practice, the applying conditions of the composites should be considered. The contents of the reinforcements should be determined by taking account of the manufacturing costs, so that we can to optimize the practical needs and to but reduce the costs

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6

Blanc, Carine. "Élaboration, caractérisation et résistance à l'usure de composites céramiques sic/tib#2." ENSMP, 1997. http://www.theses.fr/1997ENMP0804.

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Des composites denses sic-tib#2 (5, 10 et 15% vol. Tib#2) ont été élaborés par frittage naturel et réactif à partir de tio#2, b#4c, et de résine phénolique utilisée comme source de carbone, selon la réaction (qui a lieu a 1400c) : tio#2 + 0,5 b#4c + 1,5 c tib#2 + 2 co. Ils ont été caractérisés d'un point de vue microstructural, mécanique et enfin tribologique. La dispersion des particules de tib#2 s'est révélée très homogène, aussi bien en microscopie optique qu'en microscopie électronique à balayage. L'analyse d'images a montré qu'une majorité de particules à une taille inférieure à 1 m. La microscopie à force atomique et la microscopie éléctronique en transmission ont permis de mettre en évidence l'existence de particules nanométriques. Pour les propriétés mécaniques, la ténacité augmente avec le taux de tib#2, alors que la dureté diminue. En frottement, les matériaux composites s'usent moins que le sic monilithique. Les mécanismes d'usure sont modifiés aussi bien dans l'air que dans l'eau. Dans l'air, une couche de débris oxydes, protectrice si elle est stable, se forme pour les composites, alors qu'il y a formation de rouleaux pour sic. Dans l'eau, les composites sont polis, alors que sic s'use par rupture fragile (clivages). L'influence de la phase tib#2 sur la résistance à l'usure des composites se situe au niveau de la tribo-oxydation : une lubrification en régime sec peut intervenir par l'intermédiaire des produits de la tribo-oxydation.

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7

Eriksson, Mirva. "Spark plasma sintering and deformation behaviour of Titanium and Titanium/TiB₂Spark plasma sintering and deformation behaviour of Titanium and Titanium/TiB₂ composites." Licentiate thesis, Stockholm University, Department of Physical, Inorganic and Structural Chemistry, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-26122.

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Titanium has been used as a model substance to study how it behaves in a SPS apparatus when heating rate and/or pressure were varied during the sintering and deformation process. The sintering and deformation of Ti in SPS were compared with that occurring in the conventional hot pressing (HP) in order to reveal if there are any positive effects added by the use of SPS. The ductility of Ti was explored in order to understand the sintering and deformation of (Ti) x (TiB2)1-x composites with x = 0.05, 0.1, and 0.2, respectively, expressed in mol ratio. The temperature difference (DT) between the monitored and the temperature that the samples are exposed to was evaluated.

It was noticed that Ti can be sintered at relatively low temperatures. High heating rate implied that the onset temperatures of the sintering and deformation processes decreased. Increasing pressure did not affect the onset temperature but revealed that the deformation of Ti is different if the experiments are conducted within the stability region of the a -phase region of Ti or if the deformation takes place in a temperature region that covers both a-and b-phase areas, i. e. the use of high pressures implied a one step deformation process while the use of low implied that the main part of the deformation took place in the b-phase region.

(Ti) x (TiB2)1-x composites were prepared to full densities at 1500 °C using a holding time of 3 min and pressure of 50 MPa. During the SPS sintering the composite with x= 0.2 revealed the presence of TiB due to the reaction Ti + TiB 2 -> 2TiB while the composites with low x values did not show any formation of TiB. The formation of TiB impaired the mechanical properties. The deformation of composites was very difficult. Their deformability increased with increasing x and temperature as well as pressure. During the deformations of pre-sintered samples TiB was formed in all of the composites.

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8

Keller, Andrew R. "An experimental analysis of the dynamic failure resistance of TiB₂/A1₂O₃ composites." Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/16657.

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9

Skorokhod, Vladislav. "Pressureless sintering and mechanical properties of B¦4C - TiB¦2 particulate ceramic composites." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0007/NQ35979.pdf.

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10

Ferranti, Louis Jr. "Processing and characterization of microstructurally biased two-phase titanium diboride/alumina ceramica (TiB₂+Al₂O₃)." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/20008.

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11

Yuen, Chi Ho. "Wear properties of Al-based composites reinforced with in-situ and ex-situ TiB₂ particulates." access abstract and table of contents access full-text, 2004. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?msc-ap-b21174374a.pdf.

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Thesis (M.Sc.)--City University of Hong Kong, 2004.
At head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Sept. 4, 2006) Includes bibliographical references.

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12

Berger, Mattias. "Development and tribological characterisation of magnetron sputtered TiB₂ and Cr/CrN coatings." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2001. http://publications.uu.se/theses/91-554-4990-5/.

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13

Dallmeier, Kai Henrik. "Untersuchungen zur Bedeutung der preS-Domäne für den Wirtstropismus und die Infektiösität der aviären Hepatitis-B-Viren in vitro und in vivo /." [S.l. : s.n.], 2007. http://www.gbv.de/dms/tib-ub-hannover/35425670X.pdf.

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14

Kharrat, Dammak Manel. "Evolutions microstructurales, écrouissage et endommagement de composites à matrice métallique Fe-TiB₂ en chargement montone inversé." Thesis, Paris 13, 2014. http://www.theses.fr/2014PA132011/document.

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L’objectif principal de la thèse est d’analyser les mécanismes de plasticité et d’endommagement d’une nouvelle famille de composites à matrice acier Fe-TiB₂ afin de comprendre les liens microstructure/propriétés mécaniques et appliquer des modèles de comportement prenant en compte différents paramètres de la microstructure, et d’intérêt pour la mise en forme. L’étude porte sur des nuances de composites à teneur en particules fixée et différant par la taille de grain de la matrice. La caractérisation expérimentale des microstructures et textures initiales par MEB/EBSD et DRX a permis d’analyser qualitativement et quantitativement les différents paramètres morphologiques des renforts et de la matrice. L’effet de taille de grain de la matrice et des renforts sur l’écrouissage des ces composites a été étudié par essais de cisaillement simple monotone et inversés qui ont également permis de déterminer la part relative d’écrouissage cinématique des différents matériaux. L’application des résultats à une modélisation phénoménologique de l’écrouissage a permis de décrire le backstress des composites à partir de celui de la ferrite. L’analyse de l’évolution microstructurale avec la déformation de cisaillement, ainsi que des essais de flexion in situ, ont identifié la rupture des particules comme mode d’endommagement prépondérant des composites Fe-TiB₂. L’endommagement dépend de la taille de grain de la matrice, de d’endommagement des matériaux hétérogènes a permis d’estimer les contraintes de rupture des particules sur la base des résultats expérimentaux disponibles
The aim of this work was the plasticity and damage mechanisms analysis of a new steel matrix composites Fe- TiB₂ family to establish the microstructure / mechanical properties relationships then interesting for metal forming simulations in respect with various microstructural parameters. The study was focused on composites with different matrix grain size and a given particle population. The experimental characterization of initial microstructures and textures with SEM/EBSD and XRD permitted the qualitative and quantitative analysis of different morphological parameters of reinforcements and the ferritic matrix. The effect of matrix grain size and reinforcements on the composites hardening is studied based on monotonous and reverse simple shear tests which leads to determine the relative contribution of kinematic hardening. The application of a phenomenological modeling based on these results, has successfully describe the composite backstress evolution. Analysis of the microstructural evolution with shear deformation and with four points bending situ tests has shown a sensitivity of Fe-TiB₂ damage to the matrix grain size, the particles size and to the strain-path change. A damage model of heterogeneous material has been then considered and provides the particles failure stress of on the basis of the available experimental results

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15

Attar, H., M. Bönisch, M. Calin, L. C. Zhang, K. Zhuravleva, A. Funk, S. Scudino, C. Yang, and J. Eckert. "Comparative study of microstructures and mechanical properties of in situ Ti–TiB composites produced by selective laser melting, powder metallurgy, and casting technologies." Cambridge University Press, 2014. https://tud.qucosa.de/id/qucosa%3A39023.

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This study presents results of selective laser melting (SLM), powder metallurgy (PM), and casting technologies applied for producing Ti–TiB composites from Ti–TiB₂ powder. Diffraction patterns and microstructural investigations reveal that chemical reaction occurred between Ti and TiB₂ during all the three processes, leading to the formation of Ti–TiB composites. The ultimate compressive strength of SLM-processed and cast samples are 1421 and 1434 MPa, respectively, whereas the ultimate compressive strengths of PM-processed 25%, 29%, and 36% porous samples are 510, 414, and 310 MPa, respectively. The Young’s moduli of porous composite samples are 70, 45, and 23 GPa for 25%, 29%, and 36% porosity levels, respectively, and are lower than those of SLM-processed (145 GPa) and cast (142 GPa) samples. Fracture analysis of the SLM-processed and cast samples shows shear fracture and microcracks across the samples, whereas failure of porous samples occurs due to porosities and weak bonds among particles.

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16

Elfrink, Berry. "Longshore sediment transport in the swash zone /." Lyngby : Technical University of Denmark, 1996. http://www.gbv.de/dms/tib-ub-hannover/248475355.pdf.

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17

Schäfers, Stefanie. "Vom Werkbund zum Vierjahresplan : die Ausstellung Schaffendes Volk, Düsseldorf 1937 /." Düsseldorf : Droste, 2001. http://www.gbv.de/dms/tib-ub-hannover/312037619.pdf.

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18

Diederichs, Henner. "Komplexitätsreduktion in der Softwareentwicklung : ein systemtheoretischer Ansatz /." Norderstedt : Books on Demand, 2004. http://www.gbv.de/dms/tib-ub-hannover/480666784.pdf.

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19

Wittke, W. "10. Nationales Felsmechanik-Symposium : Aachen, November 1992 = 10th National Rock Mechanics Symposium /." Essen : Deutsche Gesellschaft für Erd- und Grundbau, 1993. http://www.gbv.de/dms/tib-ub-hannover/162862865.pdf.

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20

Varma, C. V. J. "Select papers /." Rotterdam : Balkema, 1997. http://www.gbv.de/dms/tib-ub-hannover/231142889.pdf.

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21

Haenel, M. W. "Vorträge der BMFT/DGMK-Tagung "Kohlewissenschaftliches Kolloquium für jüngere Wissenschaftler" : vom 30.9. bis 2.10.1992 in Freiberg/Holzhau ; Autorenmanuskripte /." Hamburg : DGMK, 1992. http://www.gbv.de/dms/tib-ub-hannover/183075870.pdf.

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22

Bülter, Martin. "Untersuchung zum Einfluß des Herstellungsprozesses auf die Oberflächenausbildung und die Umformeigenschaften von elektrolytisch verzinktem Feinblech /." Oberursel : DGM Informationsges, 1997. http://www.gbv.de/dms/tib-ub-hannover/242155812.pdf.

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23

Weber, Christian Michael. "Der Effekt von Mycophenolatmofetil im humanen koronaren 3D-Leukozytenangriffsmodell /." [S.l. : s.n.], 2006. http://www.gbv.de/dms/tib-ub-hannover/243945469.pdf.

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Ulm, Univ., Diss., 2006.
Auch als Volltextdokument (PDF) auf dem VTS der Univ. Ulm vorhanden: (http://vts.uni-ulm.de/query/browsing.type.asp?type=doctype) *** Genaue URL des vorliegenden Titels siehe Aufnahme als "Elektronische Ressource"!

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24

Kinzel, Yunjing. "Financial reportin of research and development : from HGB to IAS /." [S.l. : s.n.], 2006. http://www.gbv.de/dms/tib-ub-hannover/502877073.pdf.

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25

Dionne, Martin. "Caractérisation du composite TIB¦2-carbone avec l'aluminium liquide et le bain cryolithique des cuves d'électrolyse de l'aluminium." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ65540.pdf.

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26

Wang, Xiaoxin. "PROCESSING AND CHARACTERIZATION OF TiB ₂ -COLLOIDAL ALUMINA COATING ON CARBON CATHODE IN HALL-HEROULT CELL." University of Cincinnati / OhioLINK, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=ucin971978030.

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27

Reeves, Andrew James. "The effect of interfacial reaction on the properties of titanium-matrix composites reinforced with SiC and TiB₂ particulate." Thesis, University of Cambridge, 1992. https://www.repository.cam.ac.uk/handle/1810/251912.

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28

Hanigofsky, John. "Modeling of the chemical vapor deposition of YBa₂Cu₃O, TiB₂, and SiC thin films onto continuous ceramic tows." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/36210.

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29

Kennedy, Gregory B. "The effect of processing induced microstuctural tailoring of phase distribution on the spall strength of two-phase TIB₂-AL₂O₃ ceramic." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/20167.

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30

Gallina, Renato. "A contribuição da tecnologia industrial básica (TIB) no processo de formação e acumulação das capacidades tecnológicas de empresas do setor metal-mecânico." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/3/3136/tde-11082009-174127/.

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Nota-se que cada vez mais a sobrevivência e o crescimento das empresas industriais estão relacionadas com a possibilidade de se oferecer produtos e serviços em conformidade com as mais recentes normas internacionais. Em tal contexto, o domínio das funções tecnológicas da Tecnologia Industrial Básica TIB (metrologia, normalização e avaliação da conformidade) não é somente um requisito para a competitividade de uma empresa, mas também a base para a efetiva acumulação de capacidades tecnológicas, as quais são necessárias para a inovação bem como para o melhoramento contínuo da qualidade dos produtos e serviços. Na literatura especializada, raros são os estudos que analisam a função da TIB no processo de aprendizagem tecnológica de uma empresa. Este trabalho teve a intenção de preencher essa lacuna ao propor um modelo para avaliar e projetar as relações dinâmicas entre TIB e capacidade tecnológica. O objetivo geral deste estudo foi o de analisar a relação entre a TIB e a formação e acumulação das capacidades tecnológicas nas empresas. O estudo foi realizado através de um survey, cujo instrumento de pesquisa foi um questionário aplicado em uma amostra de 103 empresas de diferentes níveis de capacidade tecnológica do setor metalmecânico. Concluiu-se que a TIB contribui com a formação e acumulação das capacidades tecnológicas em todos os níveis e os resultados mostraram que existem associações significativas entre: (i) certificações ISO 9001/TS 16949 com as atividades de engenharia reversa; (ii) certificações ISO 17025 e de produtos com as inovações incrementais em sua linha de produtos; (iii) certificação ambiental ISO 14001 com as inovações radicais em processos/produtos, práticas de just-in-time, Kaizen, TQC/TQM e uso de sistemas integrados de informação; e (iv) sistemas inovadores de medição com as práticas de P&D e relacionamentos com instituições de C&T.
Increasingly, the survival of industrial firms is related to the possibility of offering products and services in conformity with the most recent international standards. However, the mastery of Infrastructural Technologies IfT (metrology, standardization and conformity assessment) is not only a requirement for the international competitiveness of a firm but it is also the basis for the effective accumulation of Technological Capabilities (TC) which are needed for innovation as well as the continuous improvement of the quality of products and services. In the existing literature, rare are the studies that analyze the role of IfT in the technological learning process of a firm. This work intended to fill that gap by proposing a model to assess and project the dynamic interplay between IfT and TC. The aim of this study was to analyze the relationship between IfT and the effective accumulation of TC in the firms. The study was carried out through a survey, whose instrument of research was a questionnaire applied in a sample of 103 firms of different levels of TC in metal-mechanics industry. It can be concluded that the IfT contributes with the effective accumulation of TC in all levels and the results showed that there are significant associations between: (i) accreditations ISO 9001/TS 16949 with the reversal engineering activities; (ii) accreditations ISO 17025 and of certified products in their production lines with incremental innovations in their products; (iii) ambiental accreditation by ISO 14001 with radical innovations in products/processes, activities of JIT, Kaizen, TQC/TQM and the use of information integrated systems; and (iv) innovatory systems of measurement with P&D practices and relationships with C&T institutions.

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31

Bardet, Matthieu. "Elaboration de matériaux composites à matric Titane et à nano-renforts TiC et TiB par différents procédés de métallurgie des poudres : frittage par hydruration/dehydruration et déformation plastique sévère (Equal Channel Angular Pressing (ECAP))." Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0026/document.

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Les composites à matrice Titane avec des renforts nanométriques présente des améliorations intéressantes quant aux propriétés mécaniques, sans affecter la ductilitédu matériau. Ce travail de thèse se concentre sur l’élaboration et la caractérisation dematériaux composites de Titane obtenus par deux différents procédés de métallurgie despoudres : La densification par déformation plastique sévère utilisant l’ECAP (Equal ChannelAngular Pressing) et les procédés de frittage par hydrogénation/déshydrogénation (HDH).L’ECAP est un procédé de densification rapide utilisant la déformation plastique desmatériaux, se faisant à relativement basse température. Les procédés HDH utilisent ladéshydrogénation du titane comme un levier sur les mécanismes de frittage. Les différentsnano-renforts utilisés dans ces travaux sont les particules sphériques de TiC et les aiguillesde TiB. Cette étude montre l’influence de la nature et de la forme des renforts, ainsi que duprocédé de métallurgie des poudres utilisé, sur les propriétés et la microstructure final desmatériaux denses
Titanium based composites using nano-sized reinforcements are goodcandidates for the improvement in mechanical properties without affecting ductility. Thisstudy is dedicated to fabrication and characterisation of Ti-based composites using twodifferent powder metallurgy processes: Densification using severe plastic deformation viaEqual Channel Angular Pressing (ECAP) and Hydrogenation/Dehydrogenation (HDH)sintering processes (pressureless sintering and hot pressing).ECAP is a fast process basedon a severe plastic deformation of material at relatively low temperature. HDH processes usethe dehydrogenation of Ti as a leverage of the sintering. The different nanosizedreinforcements used in this study are the TiC spherical particles and the whisker shaped TiB.This study shows the influence of either the reinforcement nature and type, and the powdermetallurgy processes used, on the final microstructure and properties of the dense materials

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32

Ropars, Ludovic. "Composites à matrice titane et renforts TiB élaborés par métallurgie des poudres : cinétique de transformations des phases, formation des microstructures et propriétés mécaniques." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0327/document.

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Les travaux réalisés dans cette thèse visent d’une part, à comprendre les évolutions structurales et microstructurales d’un composite à matrice titane et à renforts TiB au cours des différentes étapes d’élaboration par métallurgie des poudres et des traitements thermiques associés, et d’autre part, à établir des relations entre microstructures et propriétés mécaniques pour ce matériau. Les cinétiques de transformations des phases de la matrice et du renfort ont été caractérisées par DRX haute énergie in situ, au cours des différents traitements du cycle de fabrication. Des analyses de la microstructure par MEB, MEB EBSD et MET (EDX et EELS) complètent l’analyse par DRX. Il a été montré que les cinétiques de transformation de la matrice des composites sont fortement affectées (décalage d’environ 300°C vers les hautes températures de la température de transus ß) par le procédé de fabrication. Ce décalage a été associé à un enrichissement en éléments interstitiels dû au broyage mécanique des poudres et aux interstitiels présents dans les renforts TiB2 introduits pour former le TiB. L’étude in situ a aussi précisé la séquence de transformation du diborure de titane en borure TiB–B27 via la formation de la phase métastable TiB-Bf. Les analyses par MEB et MET ont permis d’atteindre et de discuter des évolutions morphologiques et spatiales des phases (matrice et borures) au cours des différents traitements, et de caractériser la composition chimique des borures. Une séquence de transformation du renfort est proposée. Enfin, des matériaux composites ont été élaborés et soumis à divers traitements thermomécaniques. Le lien entre les propriétés mécaniques statiques et les évolutions morphologiques des borures et de la matrice, comme de la texture des phases, a été abordé. Des traitements ont été proposés pour atteindre des propriétés optimales
The work done in this PhD thesis aims at the understanding of, on the one hand, the structural and microstructural evolutions of a TiB reinforced titanium matrix composite during the various steps and treatments of the powder metallurgy route used to produce it, and, on the other hand, the link between the microstructures and the mechanical properties for this material. The phase transformation kinetics, in the matrix and in the reinforcement, were characterised using in situ high energy XRD, during these treatments. Microstructural analysis, using SEM, SEM-EBSD and TEM (EDX and EELS) complete the XRD analysis. The matrix phase transformation kinetics were shown to be highly impacted by the processing route (a 300°C shift toward the high temperatures is found for the ß transus temperature). This shift has been linked with an increase in interstitial elements, coming from the powder mechanical alloying and from the interstitials in the TiB2 powder used to produce the TiB. The in situ study also helped in clarifying the transformation sequence of the TiB2 into TiB-27, via the formation of the metastable phase TiB-Bf. SEM and TEM analysis allowed to get access to and discuss the morphological and spatial evolutions of the phases (matrix and borides) during the various treatments and to characterise the chemical composition of the borides. A transformation sequence has been proposed. Finally, in a last part, composite materials were elaborated and submitted to defined heat treatments. The link between the static mechanical properties and the morphological and texture evolutions in the matrix and in the borides, was discussed. Some treatments were proposed to reach optimum mechanical properties

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Hill, Davion M. "Microstructure and mechanical properties of titanium alloys reinforced with titanium boride." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1150402807.

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Drhourhi, Allal. "Croissance en phase vapeur par flux forcé application aux dépôts de monocristaux de TiB en système ouvert et de films de Ni en système fermé." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb375972876.

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Drhourhi, Allal. "Croissance en phase vapeur par flux force : application aux depots de monocristaux de tib::(2) en systeme ouvert et films de ni en systeme ferme." Clermont-Ferrand 2, 1986. http://www.theses.fr/1986CLF21036.

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Elaboration par depot chimique et transport chimique en phase vapeur des monocristaux tib::(2). Comparaison entre les deux methodes. Developpement d'un plan de travail pour obtenir des depots reproductibles. Etude du systeme ni/nio::(4) en tube scelle. Comparaison avec le systeme ouvert. Analyse du transport des flux. Elaboration du modele du transport des flux

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Cherukuri, Balakrishna. "Microstructural Stability and Thermomechanical Processing of Boron Modified Beta Titanium Alloys." Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1229656783.

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Abreu, Carlos Eduardo Aragón. "Physiological characteristics as analyzed by hormone profile, metabolic pathways and expression of specific induced genes of C3, C4 and CAM tropical crops propagated by Temporary Immersion Bioreactors (TIB)." Doctoral thesis, ISA/UL, 2015. http://hdl.handle.net/10400.5/9264.

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Doutoramento em Engenharia Agronómica - Instituto Superior de Agronomia
Physiology and biochemistry of in vitro plants can be complex and different when compared with conventional and well known plant ex vitro behavior. Metabolic reprogramming events that occur in a number of in vitro propagated plant species give rise to low ex vitro yields as a handicap for commercial application. Temporary Immersion Bioreactors (TIB) are a method to obtain plantlet morphology and physiology much alike that of in vivo grown plants. Three tropical crops were selected for their economic importance, but also because of their different photosynthetic characteristics, to compare C4 (sugarcane) and C3-CAM (pineapple) facultative photosynthetic pathways to the more common C3-type (plantain) photosynthesis. Experiments performed using plantain and sugarcane allowed to integrate the results obtained when monitoring the oxidative stress response in C3 and C4 metabolism. Pineapple plants propagated in TIB and evaluated during acclimatization under C3 and CAM inducing conditions were used to describe the facultative C3-CAM carbon metabolism and the influence of the environmental conditions on the switch from C3 to CAM. Studies based on the modulation of in vitro conditions which reproduce abiotic stress conditions can be used for understanding the influence of upcoming climate changes on the physiology of different species
FCT

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ETT, GERHARD. "Estudo eletroquimico da co-reducao de KBFsub4 e Ksub2 TIFsub6 em meio de uma mistura eutetica de LiF-NaF-KF para a obtencao do diboreto de titanio [TIB sub 2]." reponame:Repositório Institucional do IPEN, 1999. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10772.

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Made available in DSpace on 2014-10-09T12:43:50Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:10:02Z (GMT). No. of bitstreams: 1 06778.pdf: 10838321 bytes, checksum: da09e815b4eb68ff38370a4f1987faaa (MD5)
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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Zhang, Jiaying, and jiaying zhang@rmit edu au. "Understanding Host Community Attitudes towards Tourism and Resident-Tourist Interaction: A Socio-Behavioural Study of Melbourne's Urban-Rural Fringe." RMIT University. Management, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080801.144715.

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The fast development of the tourism industry has created both positive and negative impacts on host communities. Reacting to these impacts, host residents hold various attitudes towards tourism and tourists. It has come to common agreement that a supportive host community plays a vital role in the successful and long-term development of community tourism. In order to explain the antecedents of community attitudes towards tourism, researchers have investigated the topic from both the extrinsic perspective (such as stage-based models) and the intrinsic perspective (such as the Social Exchange Theory). Nevertheless, there are still several important research gaps and deficiencies within the existing literature. First, the influence of psychological factors (personality) on attitudes towards tourism is somewhat neglected. Second, when examining the relationship between community attitudes towards tourism and the influential factors, the majority of previous studies do not distinguish the orthogonal dimensions of attitudes (such as positive dimension and negative dimension). Third, the existing literature has not addressed the issue of whether specific attitudes towards tourism will lead to a corresponding behaviour when interacting with tourists, and what other factors are determinant in host-guest interactive behaviour. Aiming to address such research gaps and deficiencies, this study has a major objective of developing a theoretical model (encompassing attitude element) to understand the antecedents of host-guest interaction. A quantitative approach was employed for the entire project. A self-administrated questionnaire survey was used to collect primary data. A total of 878 useful questionnaires were returned for analyses. Stratification sampling methods were utilized in communities where population database was accessible, while random sampling methods were used in other communities. The findings from this study confirmed the two major hypotheses in terms of community attitudes towards tourism. First, there was a significant relationship between an individual's personality and his/her attitudes towards tourism. Residents being high on Openness, Conscientiousness, Extraversion and Agreeableness traits and low on the Neuroticism trait tended to be more positive towards tourism than their counterparts. Second, while some factors were found to be influential on both positive and negative dimensions of attitudes towards tourism, others only demonstrated influences on one dimension. The Resident-Tourist Interaction Model developed in this study provided a comprehensive theoretical framework in modelling and predicting host residents' interactive behaviour towards tourists. Drawing on the evaluation results of three leading behavioural theories belonging to the school of cognition, the Model identified attitudinal, volitional, social, motivating and habitual factors for the prediction of resident-tourist interactive behaviour. Motivating factor (intention) was the critical and immediate element for action, which, in turn, was best predicted by subjective norms. External factors (gender, age and personality traits) only moderated the predictive power of the Model by less than two percent. The Model was valid and reliable for the current data. The present study advanced resident-tourist interactive behavioural study by establishing a sound theoretical framework. It also consolidated the body of knowledge in understanding community attitudes towards tourism. Findings from this study have significant practical implications for community tourism planning and management.

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Hugmark, Jon. "Stockholms trafikplanering : En jämförande studie mellan visioner, planer politiska dokument samt medborgares åsikter." Thesis, Uppsala universitet, Kulturgeografiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-297185.

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Denna studie har för avsikt att analysera hur den rådande trafikplaneringen ser ut i dagens Sverige, med fokus på Stockholm. Fokus ligger på att analysera trafikplaneringens uppkomst med bilen som utgångspunkt, hur denna har bidragit till negativa externa effekter som nu på senare tid uppmärksammats och legat till grund för ökad pådrivning mot ett trafiksystem som behöver förändras mot mer hållbara transporter, likt kollektivtrafik. Genom att analysera rådande regeringsdokument mot olika plan- och visionsdokument så kan studien bidra till att ge en mer reflekterad syn över vad som görs i realiteten mot vad mer visionära mål säger. Studien sker utifrån totalt 2 teorier samt 2 begrepp som är viktiga för att förstå dagens trafikplanering och hur resebeteende kan förändras. Mot detta är det också viktigt att se vad medborgare tycker och tänker för att se om planeringen delas av allmänheten. Detta då ökad samsyn gällande frågor och åtgärder inom trafikplaneringen kan bidra till ökad effektivitet och vilja till förändrat resebeteende. Studien har ett tydligt fokus på bilen och kollektivtrafik som transportmedel.

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Pflueger, J. [Verfasser]. "Elektronenenergieverlustspektroskopie an TiC, TiN, VC und VN / J. Pflueger." Karlsruhe : KIT-Bibliothek, 2014. http://d-nb.info/1196111693/34.

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Jones, Mark. "Properties of HVOF sprayed TiC and TiB2-based cermet coatings." Thesis, University of Nottingham, 2002. http://eprints.nottingham.ac.uk/12353/.

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This work reports research concerning the properties of cermet coatings deposited by high velocity oxy-fuel spraying, which are designed to exhibit resistance to abrasive wear and high-temperature oxidation. Cermet powders have been produced by self-propagating high-temperature synthesis (SHS) reaction of elemental powder mixtures of Fe, Cr, Ti and C or B, to produce a cermet, containing an Fe(Cr) binder phase and a hard ceramic phase, TiC or TiB2. The Ti and C content in the powder mixtures were varied in order to evaluate the effect of the C: Ti ratio of TiC on the overall integrity of three different feedstock powders and coatings produced. Four cermet coatings were produced from these SHS powders, one TiB2-based and three TiC-based. Abrasive wear resistance of the coatings was evaluated using a dry sand rubber wheel (DSRW) abrasive wear testing machine, where the coatings were subjected to abrasion by both alumina and silica abrasives. The TiB2-based coating exhibited superior wear resistance when subjected to both alumina and silica. Of the TiC-based coatings, the equimolar coating exhibited superior resistance when subjected to alumina, and the excess Ti coating exhibited superior wear resistance when subjected to abrasion with silica. When compared with coatings produced from commercially available powders, namely, sintered and crushed WC-Co and blended NiCr-Cr3C2, the coatings produced from SHS powders exhibited comparable, and in some cases, better abrasive wear properties. Preliminary oxidation tests showed that all four coatings performed well at 500°C (the temperature at which WC-Co begins to degrade rapidly). They exhibited some oxidation at 700°C, and at 900°C, exhibited severe oxidation.

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Blank, Jonathan P. "Effect of boron additions on microstructure and mechanical properties of titanium alloys produced by the armstrong process." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1198718818.

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44

García, De Cortázar Maider. "Etude de la faisabilité et du transfert de technologie pour l'alliage Ti-6Al-4V renforcé par du monoborure de titane." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2006. http://tel.archives-ouvertes.fr/tel-00129356.

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Le matériau composite à matrice de titane renforcée par des cristaux discontinus de monoborure de titane (TiB) constitue une classe nouvelle de matériaux destinés à des applications de haute technologie. Ces composites présentent des avantages car le procédé d'élaboration permet l'obtention de pièces de formes complexes à moindre coût par rapport aux composites à matrice titane renforcée par des filaments continus. Le procédé d'obtention de composites Ti/TiB nécessite deux étapes de fabrication: (1) au cours de la première étape un pré-composite de fraction volumique élevée en TiB est obtenu par un procédé d'autocombustion (SHS), (2) lors d'une seconde étape, ce composite est dilué dans l'alliage de titane liquide pour obtenir la fraction volumique désirée. Des composites de fraction volumique en TiB comprise entre 0 et 10% ont été élaborés puis caractérisés. La microstructure de la matrice est affinée et les performances mécaniques sont améliorées par la présence du TiB. Finalement, une étude technico-économique de ce procédé a été réalisée pour évaluer la viabilité industrielle du matériau et du procédé.

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Garcia, de Cortazar Maider. "Etude de la faisabilité et du transfert de technologie pour l'alliage Ti-6Al-4V renforcé par du monoborure de titaneDevelopment of a new reinforced titanium alloy : basic research and technological transfer for the Ti-6Al-4V/TiB material." bordeaux 1, 2006. http://www.theses.fr/2006BOR13195.

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Le matériau composite à matrice de titane renforcée par des cristaux discontinus de monoborure de titane (TiB) constitue une classe nouvelle de matériaux destinés à des applications de haute technologie. Ces composites présentent des avantages car le procédé d’élaboration permet l’obtention de pièces de formes complexes à moindre coût par rapport aux composites à matrice titane renforcée par des filaments continus. Le procédé d’obtention de composites Ti/TiB nécessite deux étapes de fabrication : ( 1) au cours de la première étape un pré-composite de fraction volumique élevée en TiB est obtenu par un procédé d’autocombustion ( SHS), (2) lors d’une seconde étape, ce composite est dilué dans l’alliage de titane liquide pour obtenir la fraction volumique désirée. Des composites de fraction volumique en TiB comprise entre 0 et 10% ont été élaborés puis caractérisés. La microstructure de la matrice est affinée et les performances mécaniques sont améliorées par la présence du TiB. Finalement, une étude technico-économique de ce procédé a été réalisée pour évaluer la viabilité industrielle du matériau et du procédé.

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46

Eliasson, Line Viktoria. "Rett ord til rett tid? : En kvantitativ innholdsanalyse av partilederdebattene fra valgkampen 2011." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for sosiologi og statsvitenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16987.

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Denne oppgaven er en studie av den politiske retorikken under valgkampen 2011; en valgkamp som fant sted i kjølvannet av terrorhandlingene på Utøya og i Regjeringskvartalet 22. juli samme år. Oppgaven tar utgangspunkt i teori om massemedienes spilleregler, hvordan disse endrer seg under nasjonale kriser og hvilke konsekvenser dette har for befolkningen og politikerne i et land. Ved hjelp av kvantitative analyser av partilederdebatter fra valgkampene i 2011 og 2007, gir oppgaven svar på problemstillingen: Hvordan påvirket terrorhandlingene 22. juli 2011 retorikken i den påfølgende valgkampen? Resultatene viser at valgkampretorikken var noe mildere under 2011- valgkampen, sammenlignet med valgkampen i 2007. I alle de utvalgte 2011-debattene rettet partilederne færre angrep mot de øvrige partiene, og de gjorde færre forsøk på å avbryte hverandre. Andelen personangrep var imidlertid ikke redusert under 2011-debattene. De største endringene i debattklimaet fant sted i den innledende 2011-debatten, da forhold som dreide seg om 22. juli- angrepene ble diskutert. I dette tilfellet tilpasset politikerne seg det alvorlige temaet ved å opptre mer respektfullt overfor hverandre. Da vanlige valgkampssaker var tema for diskusjon, var tonen i debatten mer lik den vi kjenner fra tidligere valgkamper. Selv om partilederdebattene fra 2011 var noe annerledes enn debattene fra 2007, var disse endringene altså ikke spesielt dominerende. Dette tyder på at partilederdebatter er institusjoner med lange tradisjoner, noe som gjør at de vanskelig endrer form.

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Gayet, Christophe. "Céramiques du système Titane-Carbone-Azote : Propriétés des phases TiN, TiCxNy et TiC." Limoges, 2000. http://www.theses.fr/2000LIMO0013.

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En partant des resultats anterieurs acquis au laboratoire sur le nitrure de titane (tin), les cycles de frittage par compression isostatique a chaud du carbure (tic) et du carbonitrure de titane (tic 0 , 5n 0 , 5) sont optimises. Les trois materiaux obtenus ont des densites relatives superieures a 99% de la densite theorique et presentent des microstructures tres proches. Les proprietes mecaniques de ces ceramiques ont ete determinees, celles du carbonitrure de titane a haute temperature ayant fait l'objet d'une etude plus specifique (resistance aux chocs thermiques, a la rupture a chaud, comportement en fluage en compression). Leur evolution est discutee en termes de teneur en azote et de porosite. La resistance a l'oxydation de tic et tic 0 , 5n 0 , 5 a ete etudiee a haute temperature et en regime dynamique d'oxygene, puis comparee a celle du nitrure tin. Dans les trois cas, le processus limitant est diffusionnel, la couche de rutile dense externe jouant le role de barriere de diffusion. La derniere partie de ce travail concerne la realisation d'une liaison ceramique/metal entre les materiaux cic et le nickel massif : - le brasage diffusion implique la formation d'une phase liquide interfaciale a une temperature inferieure a la temperature de fusion du nickel (formation in situ de la brasure), - deux plaques de carbonitrure de titane sont assemblees par soudage diffusion en utilisant du nickel comme intermediaire de liaison (modelisation des contraintes thermiques a l'aide du code de calcul par elements finis abaqus). En definitive, cette etude a permis de preciser et de comparer les proprietes des ceramiques du systeme titane/carbone/azote densifiees par cic en fonction du rapport n/(c + n).

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Cheng, Man Fai. "Wear properties of Al-based composites reinforced with in-situ TiC and TiB2 particulates." access abstract and table of contents access full-text, 2004. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?msc-ap-b2117409xa.pdf.

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Thesis (M.Sc.)--City University of Hong Kong, 2004.
At head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Aug. 31, 2006) Includes bibliographical references.

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49

LORY, CLAUDE. "Etude de la croissance et des proprietes des couches de tin, tic et i-c obtenues par depots ioniques (ion plating) : application, realisation de revetements multicouches tin + ti(n,c) + tic + i-c." Limoges, 1988. http://www.theses.fr/1988LIMO0037.

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On etudie l'influence des parametres de depot sur les mecanismes de croissance et les proprietes des films de nitrure de titane (tin), de carbure de titane (tic) et de carbone dur amorphe (i-c) obtenus par depot ionique, en relation avec leur comportement tribologique et antiusure

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Rudolph, Pascale. "Physikalische Chemie der Laser-Material-Wechselwirkung mit Ba-Al-Borosilikatglas, AlN, SiC, SiC-TiC-TiB2." [S.l.] : [s.n.], 2001. http://www.diss.fu-berlin.de/2002/31/index.html.

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Dissertations / Theses on the topic 'TIB'

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