Download or read book Formation des micro fissures aux joints des grains written by Markus Theodor Welsch and published by . This book was released on 2011 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: La plupart des matériaux sont par nature anisotropies (élastiques, plastiques). Ces anisotropies peuvent présenter des directions favorables ou peuvent au contraire détériorer les propriétés mécaniques des polycristaux. Dans le second cas, les anisotropies des propriétés mécaniques entraînent des déformations élastiques, des contraintes internes, ainsi que des rotations élastiques locales supplémentaires. Ces contraintes additionnelles sont à l’origine de dommages locaux, comme par exemple des porosités ou la propagation de microfissures. L’amplitude de ces contraintes est fortement dépendante à la fois de l’alignement des joints de grains avec la direction des sollicitations mécaniques et de la désorientation entre grains. Dans ce travail, l’influence des hétérogénéités microstructurales sur les contraintes internes dans les zones proches des joints de grains après des essais de fatigue (en traction et en flexion) ont été étudiée expérimentalement et théoriquement. Pour cette étude, nous avons choisi d’étudier des tôles de nickel pur et de Fe-3%Si. Ces matériaux sont connus pour leurs facteurs d’anisotropie élastique élevés. L’utilisation d’un microscope optique a permis la détermination de l’alignement des joints de grains. L’orientation cristallographique locale est déterminée par EBSD. Ces données expérimentales sont la base d’un modèle élément fini 3D en élasticité. Ces simulations ont permis la détermination de fortes contraintes internes dans les zones proches des joints de grains. Nous avons d’ailleurs observé expérimentalement que des microfissures apparaissent dans ces zones. L’utilisation d’un microscope électronique à balayage équipé du système ECCI permet d’observer les structures de dislocation formées au cours de la déformation dans les zones proches des joints de grains. Par exemple après un essai de fatigue, on observe que les structures de dislocation ne sont pas uniformément réparties dans les grains. En parallèle, la nano-indentation a été utilisée pour déterminer localement les différences de propriétés mécaniques causées par le durcissement local. Le microscope à force magnétique s’avère également une méthode efficace pour observer les structures de dislocation dans le nickel. Le but de toutes ces caractérisations est de contribuer à la compréhension de la formation des fissures et des mécanismes de propagation de fissure et aussi de prédire la position des fissures

Download or read book Etudes Et Documentation Metallurgiques written by and published by . This book was released on 1952 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings written by and published by . This book was released on 1964 with total page 1196 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book CNRM written by Centre national de recherches métallurgiques and published by . This book was released on 1966 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 3rd International Conference on Mechanical and Physical Behaviour of Materials Under Dynamic Loading written by and published by . This book was released on 1991 with total page 988 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Material Forming and Joining written by R. Ganesh Narayanan and published by Springer. This book was released on 2015-04-24 with total page 385 pages. Available in PDF, EPUB and Kindle. Book excerpt: This edited book contains extended research papers from AIMTDR 2014. This includes recent research work in the fields of friction stir welding, sheet forming, joining and forming, modeling and simulation, efficient prediction strategies, micro-manufacturing, sustainable and green manufacturing issues etc. This will prove useful to students, researchers and practitioners in the field of materials forming and manufacturing.

Download or read book Journal de physique written by and published by . This book was released on 2003 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings written by International Council of the Aeronautical Sciences and published by . This book was released on 1964 with total page 1196 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Coupled Thermo Hydro Mechanical Chemical Processes in Geo systems written by Ove Stephansson and published by Elsevier. This book was released on 2004-11-03 with total page 853 pages. Available in PDF, EPUB and Kindle. Book excerpt: Among the most important and exciting current steps forward in geo-engineering is the development of coupled numerical models. They represent the basic physics of geo-engineering processes which can include the effects of heat, water, mechanics and chemistry. Such models provide an integrating focus for the wide range of geo-engineering disciplines. The articles within this volume were originally presented at the inaugural GeoProc conference held in Stockholm and contain a collection of unusually high quality information not available elsewhere in an edited and coherent form. This collection not only benefits from the latest theoretical developments but also applies them to a number of practical and wide ranging applications. Examples include the environmental issues around radioactive waste disposal deep in rock, and the search for new reserves of oil and gas.

Download or read book Advances in Aeronautical Sciences written by International Council of the Aeronautical Sciences and published by . This book was released on 1964 with total page 1216 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Water Infusion for Coal Mine Dust Control written by and published by . This book was released on 1987 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Failure Analysis of Heat Treated Steel Components written by Lauralice de Campos Franceschini Canale and published by ASM International. This book was released on 2008 with total page 651 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Report of Investigations written by and published by . This book was released on 1987 with total page 684 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Principles of Corrosion Engineering and Corrosion Control written by Zaki Ahmad and published by Elsevier. This book was released on 2006-09-18 with total page 673 pages. Available in PDF, EPUB and Kindle. Book excerpt: Corrosion is a huge issue for materials, mechanical, civil and petrochemical engineers. With comprehensive coverage of the principles of corrosion engineering, this book is a one-stop text and reference for students and practicing corrosion engineers. Highly illustrated, with worked examples and definitions, it covers basic corrosion principles, and more advanced information for postgraduate students and professionals. Basic principles of electrochemistry and chemical thermodynamics are incorporated to make the book accessible for students and engineers who do not have prior knowledge of this area. Each form of corrosion covered in the book has a definition, description, mechanism, examples and preventative methods. Case histories of failure are cited for each form. End of chapter questions are accompanied by an online solutions manual.* Comprehensively covers the principles of corrosion engineering, methods of corrosion protection and corrosion processes and control in selected engineering environments* Structured for corrosion science and engineering classes at senior undergraduate and graduate level, and is an ideal reference that readers will want to use in their professional work* Worked examples, extensive end of chapter exercises and accompanying online solutions and written by an expert from a key pretochemical university

Download or read book Welding Design Procedures and Inspection written by and published by . This book was released on 1985 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Joining of Stainless Steels written by American Society for Metals and published by . This book was released on 1967 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Materials Technology for Fossil Power Plants written by and published by ASM International. This book was released on 2011-01-01 with total page 1122 pages. Available in PDF, EPUB and Kindle. Book excerpt: