Download or read book Endommagement des aciers TWIP pour application automobile written by Julie Lorthios and published by . This book was released on 2011 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: Grâce à l'optimisation de l'effet TWIP (Twinning Induced Plasticity) et à la maîtrise de la microstructure (basse énergie de défaut d'empilement, austénite stable à grains fins), les aciers austénitiques Fe-Mn-C combinent une excellente ductilité à une résistance mécanique élevée. L'étude s'intéresse aux paramètres mécaniques critiques menant à la rupture ductile en mode slant (biseau dans l'épaisseur) et aux aspects physiques de l'endommagement dans le but de déterminer un critère de rupture quantitatif. Le comportement plastique de l'acier TWIP présente un caractère anisotrope et cinématique avec une déformation hétérogène en traction uniaxiale due à un mécanisme de pseudo-vieillissement dynamique. Après avoir déterminé la loi de comportement, la courbe limite de formage a pu être établie par comparaison entre résultats expérimentaux et prédictions du modèle mécanique, dans une large gamme de triaxialité des contraintes. Quel que soit le mode de déformation considéré, la rupture s'effectue brutalement en mode slant sans striction localisée. Peu d'endommagement, y compris en trois dimensions, a été observé autour des zones de rupture. Un critère de rupture phénoménologique basé sur la contrainte équivalente et sur l'angle de Lode, redéfinis tous deux dans l'équivalent de Barlat, permet de prédire de façon correcte la formabilité de l'acier TWIP. L'influence de la pression hydrostatique et du mécanisme de pseudo vieillissement dynamique sur la courbe limite de formage est discutée.
Download or read book Etude de l endommagement par la d coupe des aciers dual phase pour application automobile written by Alexandre Dalloz and published by . This book was released on 2007 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: Des observations récentes ont montré que l’étape de découpe mécanique avait tendance à altérer la formabilité des aciers dual phase. L’objectif de la présente étude est d’améliorer notre connaissance des mécanismes mis en jeu au cours de la découpe afin de pouvoir les prendre en compte pour le développement des futures nuances. Un premier travail d’observation et de caractérisation a révélé l’existence d’une zone affectée par la découpe s’étendant sur environ 200 mm. Cette zone se caractérise par une déformation microstructurale importante, conduisant localement à la décohésion des phases ferritique et martensitique. La formation de cette zone en cours de découpe a été étudiée à travers deux approches : d’une part, via un montage de cisaille instrumenté permettant d’observer l’évolution de la microstructure, et, d’autre part, via la simulation numérique du procédé donnant accès aux grandeurs mécaniques locales dans la tôle. Il apparait que l’endommagement et la rupture de l’acier sont pilotés par la décohésion des interfaces ferrite-martensite, elle-même fortement dépendante de l’état de triaxialité des contraintes. L’étude du comportement des bords découpés au cours de sollicitation mécanique a permis d’observer l’amorçage rapide de fissures dans la zone affectée par la découpe et l’impact direct de la taille de cette dernière sur la perte de ductilité des pièces découpées. Enfin, deux traitements thermiques permettant de limiter l’impact de la découpe ont été mis en évidences: d’une part via la transformation d’une troisième phase lors du recuit, d’autre part via le rééquilibrage des propriétés au sein de la microstructure par l’application d’un traitement de revenu.
Download or read book tude de l endommagement en fatigue thermique des aciers inoxydables F17TNb et R20 12 pour application automobile written by Laurent Bucher and published by . This book was released on 2004 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les collecteurs d'échappement des véhicules automobiles sont des pièces sollicitées en fatigue thermique de manière prépondérante. Pour la fabrication de ces pièces, les aciers inoxydables viennent aujourd'hui concurrencer la fonte traditionnellement utilisée. Afin de qualifier les différentes nuances de sa gamme vis-à-vis de cette application, la société Ugine & ALZ, fabricant d'aciers inoxydables, a développé un essai original de fatigue thermique. Si cet essai apparaît représentatif des sollicitations thermomécaniques subies par les collecteurs en zones critiques, différents mécanismes de ruine sont observés entre les nuances ferritiques et austénitiques. Le sujet de la présente thèse concerne l'endommagement en fatigue thermique d'aciers inoxydables pour l'application automobile collecteur d'échappement. Deux aciers inoxydables sont étudiés: une nuance ferritique nommée F17TNb (17%Cr stabilisé Ti et Nb) et une nuance austénitique nommée R20-12 (20%Cr et 12%Ni). Le premier objectif est de comprendre la différence d'endommagement apparaissant en fatigue thermique entre les nuances ferritiques et austénitiques. Le second objectif est de développer un outil de dimensionnement des structures sollicitées en fatigue thermique.
Download or read book Dictionary of the French and English Languages written by Gabriel Surenne and published by . This book was released on 1856 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A German English Dictionary for Chemists written by Austin M 1876-1956 Patterson and published by Scholar Select. This book was released on 2015-08-08 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Download or read book Metal Forming and the Finite Element Method written by the late Shiro Kobayashi and published by Oxford University Press. This book was released on 1989-03-09 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: The application of computer-aided design and manufacturing techniques is becoming essential in modern metal-forming technology. Thus process modeling for the determination of deformation mechanics has been a major concern in research . In light of these developments, the finite element method--a technique by which an object is decomposed into pieces and treated as isolated, interacting sections--has steadily assumed increased importance. This volume addresses advances in modern metal-forming technology, computer-aided design and engineering, and the finite element method.
Download or read book Adiabatic Shear Localization written by Bradley Dodd and published by Elsevier. This book was released on 2012-05-22 with total page 469 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adiabatic shear localization is a mode of failure that occurs in dynamic loading. It is characterized by thermal softening occurring over a very narrow region of a material and is usually a precursor to ductile fracture and catastrophic failure. This reference source is the revised and updated version of the first detailed study of the mechanics and modes of adiabatic shear localization in solids. Building on the success of the first edition, the book provides a systematic description of a number of aspects of adiabatic shear banding. The concepts and techniques described in this work can usefully be applied to solve a multitude of problems encountered by those investigating fracture and damage in materials, impact dynamics, metal working and other areas. Specific chapters focus on energetic materials, polymers, bulk metal glasses, and the mathematics of shear banding as well as the numerical modeling of them. With its detailed coverage of the subject, this book is of great interest to academics and researchers into materials performance as well as professionals. - Up-to-date coverage of the subject and research that has occurred over the past 20 years - Each chapter is written on a different sub-field of adiabatic shear by an acknowledged expert in the field - Detailed and clear discussions of each aspect
Download or read book A New Pocket Dictionary of the French and English Languages in Two Parts written by Thomas Nugent and published by . This book was released on 1770 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Livestock Policy Analysis written by International Livestock Research Institute and published by ILRI (aka ILCA and ILRAD). This book was released on 1995-01-01 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Policy concepts; Identification of policy issues; Production systems, supply and demand; Market, price and trade policies; Marketing and distribution systems; Budget and manpower planning; Land tenure police for the livestock sector; Policy analysis report writing and communication; Livestock production and marketing in alphabeta - a case study.
Download or read book Historical Dictionary of Iran written by John Henry Lorentz and published by Historical Dictionaries of Asia, Oceania, and the Middle East. This book was released on 2007 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides an overview of specific events, movements, people, political and social groups, places, trends, and chronology. Allows for considerable exploration of a number of historical and contemporary topics and issues. The modern period, defined as 1800-present, is covered extensively.
Download or read book Nijinsky s Crime Against Grace written by Millicent Hodson and published by Pendragon Press. This book was released on 1996 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: The efforts of the three collaborators resulted in a spectacle that bore little resemblance to ballet. During the premiere at the Theatre des Champs-Elysees on May 29, 1913, Parisians were incited to riot by the strange tension of the dancing and stark contrasts of the music and decor. The premiere of Le Sacre du Printemps became a legend overnight, and the notoriety of this event began immediately to distort the significance of the work, especially Nijinsky's choreography. He declared to the London Daily Mail on July 12, 1913, "I am accused, of a crime against grace."
Download or read book Expositions and Developments written by Igor Stravinsky and published by Univ of California Press. This book was released on 2023-11-10 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: This title is part of UC Press's Voices Revived program, which commemorates University of California Press’s mission to seek out and cultivate the brightest minds and give them voice, reach, and impact. Drawing on a backlist dating to 1893, Voices Revived makes high-quality, peer-reviewed scholarship accessible once again using print-on-demand technology. This title was originally published in 1962.
Download or read book Agricultural English written by Georgeta Raţă and published by Cambridge Scholars Publishing. This book was released on 2012-04-25 with total page 385 pages. Available in PDF, EPUB and Kindle. Book excerpt: Agricultural English is a collection of essays on the English of Agriculture. The approach is a linguistic one: the different aspects of the English used in the field of agriculture (agricultural practices, agricultural systems) and in some fields related to agriculture (agricultural zoology, agri-tourism, biology, botany, ecology, entomology, gastronomy, land measurement, plant pathology, zoology) are analysed from a morphological (combination, derivation), syntactical (nominal phrases, verbal phrases), lexical and lexicographical, semantic (homonymy, semantic fields, synonymy, terminology), pragmatic (academic discourse, idiom, metaphor), etymological (etymon, Latin heritage), and contrastive (English–Croatian, English–French, English–German, English–Romanian, Romanian–English) points of view. The book will appeal to agriculturists, animal breeders, professors, researchers, students, and translators from Croatian-, English-, French-, German-, and Romanian-speaking countries, active in their own countries or abroad. The types of academic readership it would appeal to include academic teaching staff, researchers and students in the fields of agriculture and related fields – agricultural zoology, agri-tourism, biology, botany, ecology, entomology, gastronomy, land measurement, plant pathology, and zoology.
Download or read book Adiabatic Shear Localization written by Yilong Bai and published by Pergamon. This book was released on 1992-01-01 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adiabatic shear localization is a mode of failure that occurs in dynamic loading. It is characterized by thermal softening occurring over a very narrow region of a material and is usually a precursor to ductile fracture and catastrophic failure. This reference source is the first detailed study of the mechanics and modes of adiabatic shear localization in solids, and provides a systematic description of a number of aspects of adiabatic shear banding. The inclusion of the appendices which provide a quick reference section and a comprehensive collection of thermomechanical data allows rapid access and understanding of the subject and its phenomena. The concepts and techniques described in this work can usefully be applied to solve a multitude of problems encountered by those investigating fracture and damage in materials, impact dynamics, metal working and other areas. This reference book has come about in response to the pressing demand of mechanical and metallurgical engineers for a high quality summary of the knowledge gained over the last twenty years. While fulfilling this requirement, the book is also of great interest to academics and researchers into materials performance.
Download or read book Historical Dictionary of Pakistan written by Shahid Javed Burki and published by . This book was released on 1999 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pakistan is unlike most other countries in the emerging world. It is one of the two nations – the other being the state of Israel – founded on the basis of religion. Although it was created to provide a homeland for the Muslim community of British India, in its original form it was able to accommodate only about half of the people of Islamic faith who lived in the subcontinent. Pakistan’s birth in 1947 resulted in one of the largest movements of people in human history when some 14 million people left their homes, with 8 million Muslims leaving India for what is now Pakistan and 6 million Hindus and Sikhs moving in the opposite direction. This was the first large-scale incidence of ethnic cleansing the world was to witness. --
Download or read book The Lost Rite written by Millicent Hodson and and published by . This book was released on 2015-09-01 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The story of how the legendary lost ballet, 'The Rite of Spring' (Le Sacre du Printemps) was recreated by Millicent Hodson and Kenneth Archer, including a Spectator's Guide with stop-frame photographs by Shira Klasmer of the Polish National Ballet onstage in the reconstructed 'Rite', together with quotes by observers from the time so that readers can 'see' the ballet as they 'hear' the voices of 1913.
Download or read book Schoenberg and the New Music written by Carl Dahlhaus and published by Cambridge University Press. This book was released on 1987 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a collection of essays, by the leading German musicologist of our day, on one of the most controversial and influential composers of our century: Arnold Schoenberg. Schoenberg is considered here as a historical figure, as a thinker and theoretician and as a composer whose works may be subjected to technical analysis and/or examined in relation to the history of ideas. Above all, he is considered in the context of the 'New Music', the historical and cultural movement of the first two decades of this century which embrace musicians such as Webern, Schreker and Scriabin (all of whom are allotted individual essays), as well as Schoenberg himself. In addition to historical and analytical essays there are essays of a broader cultural-historical and even sociological import which should interest all those involved with twentieth-century music and ideas.
