Download or read book Etude des m canismes de recristallisation de nouveaux alliages base de Ni written by Wei Wang (auteur d'une thèse de Génie des matériaux).) and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les travaux portent sur deux nuances d'alliages Ni-Cr-W, l'une contenant des précipités de W (EM722) et l'autre non (EM721). Les matériaux forgés, fournis par Aubert & Duval, présentaient des microstructures hétérogènes avec de très gros grains. Dans un premier temps, une procédure thermomécanique a été développée afin d'obtenir un état de référence avec une microstructure homogène avec une faible taille de grains et une texture relativement peu accusée. A partir de cet état de référence, l'évolution de la texture, au cours du laminage à froid (différents taux de réduction), a été analysée par diffraction des neutrons et a montré un renforcement de la texture de type Laiton. Les mécanismes de déformation ont été étudiés en microscopie électronique en transmission et par EBSD (Electron BackScatter Diffraction) afin de comprendre la formation de ce type de texture. Les bandes de cisaillement sont supposées être un facteur important pour la formation de ce type de texture. A partir des états déformés, la cinétique de recristallisation a été déterminée pour deux températures (700°C et 900°C) à partir de mesures de microdureté et par EBSD. Les mécanismes de recristallisation ont été étudiés par MET. Le mécanisme de SIBM (Strain Induced grain Boundary Migration) est le mécanisme prépondérant pour la nuance EM721. Pour l'autre nuance, EM722, possédant des précipités de W, le mécanisme de SIBM est présent, mais en plus, un second mécanisme de PSN (Particle Stimulated Nucleation) a été mis en évidence. De plus, quel que soit le mécanisme de recristallisation, une fois que les germes sont formés, ils maclent très rapidement. Par conséquent, une étude complémentaire sur l'évolution des joints de macle pendant la recristallisation primaire a été réalisée, en employant l'EBSD et surtout le système ASTAR installé dans un MET. Il a alors été montré que cette évolution dépend à la fois de la taille des grains et de l'énergie stockée par les grains pendant la déformation. Enfin, une simulation de la recristallisation primaire de type Monte-Carlo a également été mise en œuvre. Son originalité réside notamment dans sa capacité à rendre compte de la formation des joints de macles cohérents et rectilignes.

Download or read book ETUDE DES MECANISMES DE RECRISTALLISATION DANS L INVAR ALLIAGE FE 36 NI written by FRANCK.. JULLIARD and published by . This book was released on 2001 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: LES MECANISMES DE RECRISTALLISATION SONT ETUDIES DANS L'INVAR, ALLIAGE FE-36%NI UTILISE COMME MASQUE D'OMBRES DANS LES TELEVISEURS COULEUR, AFIN DE COMPRENDRE LA FORMATION DE LA TEXTURE DE RECRISTALLISATION CUBIQUE QUI EST UN DES PARAMETRES FAVORISANT LE PERCAGE CHIMIQUE DES MASQUES. NOUS AVONS CARACTERISE A DIFFERENTES ECHELLES LA TEXTURE ET LA MICROSTRUCTURE DU MATERIAU AU COURS DES DIFFERENTES ETAPES DE LA GAMME DE FABRICATION EN UTILISANT LA DIFFRACTION DES RAYONS X ET DES NEUTRONS, LA MICROSCOPIE OPTIQUE ET LA MICROSCOPIE ELECTRONIQUE A BALAYAGE ET EN TRANSMISSION. LE MATERIAU MONTRE APRES UN LAMINAGE A CHAUD UNE STRUCTURE RECRISTALLISEE A GRAINS FINS ET UNE TEXTURE PEU MARQUEE ET HETEROGENE ENTRE LA SURFACE ET LE CUR OU LES GRAINS D'ORIENTATION CUBIQUES SONT FORTEMENT PRESENTS. AU COURS DU LAMINAGE A FROID, CETTE TEXTURE PEU ACCUSEE EVOLUE RAPIDEMENT VERS UNE FORTE TEXTURE DE TYPE CUIVRE DANS LAQUELLE LA COMPOSANTE CUBIQUE RESTE PRESENTE QUELQUE SOIT LE TAUX DE REDUCTION. LES GRAINS DE CETTE ORIENTATION DEVELOPPENT ALORS UNE STRUCTURE DE CELLULES BIEN RESTAUREES. DE PLUS, LA DESORIENTATION SE CUMULE A L'INTERIEUR DES BANDES CUBIQUES, PASSANT DE 10\ POUR UN TAUX DE REDUCTION DE 70% A PLUS DE 30\ POUR UN TAUX DE REDUCTION DE 95%. LORS DU RECUIT, LE MATERIAU DEVELOPPE UNE TEXTURE DE RECRISTALLISATION CUBIQUE POUR UN TAUX DE REDUCTION SUPERIEUR A 80%, ALORS QU'ELLE EST BEAUCOUP MOINS MARQUEE EN DESSOUS DE 80%. A L'ECHELLE MICROSCOPIQUE, LA CROISSANCE DES GERMES D'ORIENTATION CUBIQUE S'OPERE PAR GONFLEMENT DE L'EX-JOINT DE GRAINS DE FORTE DESORIENTATION QUELQUE SOIT LE TAUX DE LAMINAGE. LA DIFFERENCE DE TEXTURE DE RECRISTALLISATION PEUT ALORS S'EXPLIQUER PAR UNE PLUS FAIBLE DIFFERENCE D'ENERGIE STOCKEE ENTRE LA MATRICE ET LES BANDES CUBIQUES DANS LE MATERIAU MODEREMENT LAMINE. EN EFFET, LA FORCE MOTRICE EST PAR CONSEQUENT PLUS FAIBLE ET LA CROISSANCE DES GERMES MOINS RAPIDE. AINSI, LES AUTRES COMPOSANTES ONT LE TEMPS DE SE DEVELOPPER.

Download or read book Etude des m canismes de germination de la cristallisation dans un alliage Ni Si B amorphe written by Marc-Henri Zürcher and published by . This book was released on 1989 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Etude de la d formation chaud des alliages mod les nickel niobium written by Nedjoua Matougui and published by Editions Universitaires Europeennes. This book was released on 2021-09-06 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cet ouvrage traite une étude expérimentale et modélisation du comportement mécanique des alliages modèles nickel niobium au cours de leurs déformation à chaud. Ceci menera à améliorer les connaissances actuelles sur la déformation à chaud des superalliages à base de nickel, destinés pour la fabrication des disques de turbines (terrestres, aéronautique ou autres). L'objectif principal est d'établir l'influence de la teneur en niobium en solution solide sur le comportement de déformation à chaud d'alliages binaires de haute pureté à base de nickel. Pour ce faire, différents matériaux modèles Ni-Nb (Ni-0,01, 0,1, 1, 2, 5 et 10%Nb, + Ni pur), ont été élaborés et déformés en torsion à chaud à différentes températures (800, 900 et 1000°C) et vitesses de déformation (0.03, 0.1 et 0.3 s-1). Cette large gamme de conditions expérimentales est en mesure de déterminer les caractéristiques rhéologiques essentielles et l'influence de l'addition de niobium sur le comportement de la recristallisation dynamique, de caractériser les microstructures et microtextures de ces alliages par la technique moderne EBSD, et de proposer un concept de quantification de la taille des grains via le modele DDRX.

Download or read book Etude des m canismes de germination de la cristallisation dans un alliage Ni Si B amphore written by Marc-Henri Zürcher and published by . This book was released on 1989 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Metals Abstracts written by and published by . This book was released on 1972 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Journal of the Iron and Steel Institute written by Iron and Steel Institute and published by . This book was released on 1920 with total page 880 pages. Available in PDF, EPUB and Kindle. Book excerpt: Includes sect. "A survey of literature on the manufacture and properties of iron and steel, and kindred subjects" (title varies)

Download or read book Superalloys 2000 written by Ken Green and published by Tms. This book was released on 2000-01-01 with total page 860 pages. Available in PDF, EPUB and Kindle. Book excerpt: This proceedings volume covers all aspects of development, production, behavior, and integration of super-alloys and related high-temperature materials for use in gas turbines for aircraft, power generation, and other applications.

Download or read book Design and Modeling of Mechanical Systems written by Mohamed Haddar and published by Springer Science & Business Media. This book was released on 2013-03-12 with total page 653 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 5th International Congress on Design and Modeling of Mechanical Systems (CMSM) was held in Djerba, Tunisia on March 25-27, 2013 and followed four previous successful editions, which brought together international experts in the fields of design and modeling of mechanical systems, thus contributing to the exchange of information and skills and leading to a considerable progress in research among the participating teams. The fifth edition of the congress (CMSM ́2013), organized by the Unit of Mechanics, Modeling and Manufacturing (U2MP) of the National School of Engineers of Sfax, Tunisia, the Mechanical Engineering Laboratory (MBL) of the National School of Engineers of Monastir, Tunisia and the Mechanics Laboratory of Sousse (LMS) of the National School of Engineers of Sousse, Tunisia, saw a significant increase of the international participation. This edition brought together nearly 300 attendees who exposed their work on the following topics: mechatronics and robotics, dynamics of mechanical systems, fluid structure interaction and vibroacoustics, modeling and analysis of materials and structures, design and manufacturing of mechanical systems. This book is the proceedings of CMSM ́2013 and contains a careful selection of high quality contributions, which were exposed during various sessions of the congress. The original articles presented here provide an overview of recent research advancements accomplished in the field mechanical engineering.

Download or read book Journal of the Institute of Metals written by Institute of Metals and published by . This book was released on 1928 with total page 944 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues for Sept. 1951- include the Bulletin.

Download or read book The Boundaries of the West African Craton written by Nasser Ennih and published by Geological Society of London. This book was released on 2008 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Molecular Beam Epitaxy written by John Wilfred Orton and published by . This book was released on 2015 with total page 529 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book is a history of Molecular Beam Epitaxy (MBE) as applied to the growth of semiconductor thin films (note that it does not cover the subject of metal thin films). It begins by examining the origins of MBE, first of all looking at the nature of molecular beams and considering their application to fundamental physics, to the development of nuclear magnetic resonance and to the invention of the microwave MASER. It shows how molecular beams of silane (SiH4) were used to study the nucleation of silicon films on a silicon substrate and how such studies were extended to compound semiconductors such as GaAs. From such surface studies in ultra-high vacuum the technique developed into a method of growing high quality single crystal films of a wide range of semiconductors. Comparing this with earlier evaporation methods of deposition and with other epitaxial deposition methods such as liquid phase and vapour phase epitaxy (LPE and VPE). The text describes the development of MBE machines from the early 'home-made' variety to that of commercial equipment and show how MBE was gradually refined to produce high quality films with atomic dimensions. This was much aided by the use of various in-situ surface analysis techniques, such as reflection high energy electron diffraction (RHEED) and mass spectrometry, a feature unique to MBE. It looks at various modified versions of the basic MBE process, then proceed to describe their application to the growth of so-called 'low-dimensional structures' (LDS) based on ultra-thin heterostructure films with thickness of order a few molecular monolayers. Further chapters cover the growth of a wide range of different compounds and describe their application to fundamental physics and to the fabrication of electronic and opto-electronic devices. The authors study the historical development of all these aspects and emphasise both the (often unexpected) manner of their discovery and development and the unique features which MBE brings to the growth of extremely complex structures with monolayer accuracy.

Download or read book Microalloying 75 written by and published by . This book was released on 1977 with total page 772 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Metallurgy and Mechanics of Welding written by Regis Blondeau and published by John Wiley & Sons. This book was released on 2013-03-01 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a comprehensive overview on the subject of welding. Written by a group of expert contributors, the book covers all welding methods, from traditional to high-energy plasmas and lasers. The reference presents joint welding, stainless steel welding, aluminum welding, welding in the nuclear industry, and all aspects of welding quality control.

Download or read book Flexoelectricity in Liquid Crystals written by Agnes Buka and published by World Scientific. This book was released on 2013 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book intends to give a state-of-the-art overview of flexoelectricity, a linear physical coupling between mechanical (orientational) deformations and electric polarization, which is specific to systems with orientational order, such as liquid crystals. Chapters written by experts in the field shed light on theoretical as well as experimental aspects of research carried out since the discovery of flexoelectricity. Besides a common macroscopic (continuum) description the microscopic theory of flexoelectricity is also addressed. Electro-optic effects due to or modified by flexoelectricity as well as various (direct and indirect) measurement methods are discussed. Special emphasis is given to the role of flexoelectricity in pattern-forming instabilities. While the main focus of the book lies in flexoelectricity in nematic liquid crystals, peculiarities of other mesophases (bent-core systems, cholesterics, and smectics) are also reviewed. Flexoelectricity has relevance to biological (living) systems and can also offer possibilities for technical applications. The basics of these two interdisciplinary fields are also summarized.

Download or read book Theory of X Ray Diffraction in Crystals written by William H. Zachariasen and published by Dover Publications. This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This classic by one of the great figures in x-ray structure analysis provides a vigorous mathematical treatment of its subject. Addresses such fundamentals as crystal faces and edges, the lattice postulate, lattice rows and panes, as well as point, translation, and space groups. 1945 edition.

Download or read book Nickel and Chromium Plating written by J. K. Dennis and published by Butterworth-Heinemann. This book was released on 2013-10-22 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nickel and Chromium Plating, Second Edition, does not merely update the first edition but also places additional emphasis on certain methods that have achieved increased industrial use in the 14 years since the first edition was published. The book begins by tracing the history of nickel and chromium plating. This is followed by a discussion of the electrochemistry of electrodeposition from aqueous electrolyte solutions. Separate chapters cover topics such as autocatalytic (electroless) nickel deposition; nickel plating onto aluminum and other difficult substrates; plating onto plastics and high-speed plating; the deposition of various nickel alloys for decorative and functional applications; composite coatings; and tampon (brush) plating. This book will be helpful to those new to the plating industry; those experienced in the industry will find that this revised version enables them to keep up-to-date with the latest developments in this specialized technology.