Fatigue of Materials and Structures E-Book

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 420

Veröffentlichungsjahr: 2013

Beschreibung

The design of mechanical structures with improved and predictable durability cannot be achieved without a thorough understanding of the mechanisms of fatigue damage and more specifically the relationships between the microstructure of materials and their fatigue properties. Written by leading experts in the field, this book (which is complementary to Fatigue of Materials and Structures: Application to Damage and Design, also edited by Claude Bathias and André Pineau), provides an authoritative, comprehensive and unified treatment of the mechanics and micromechanisms of fatigue in metals, polymers and composites. Each chapter is devoted to one of the major classes of materials or to different types of fatigue damage, thereby providing overall coverage of the field. The book deals with crack initiation, crack growth, low-cycle fatigue, gigacycle fatigue, shorts cracks, fatigue micromechanisms and the local approach to fatigue damage, corrosion fatigue, environmental effects and variable amplitude loadings, and will be an important and much used reference for students, practicing engineers and researchers studying fracture and fatigue in numerous areas of mechanical, structural, civil, design, nuclear, and aerospace engineering as well as materials science.

Leseprobe

Table of Contents

Foreword

Chapter 1. High Temperature Fatigue

1.1. Introduction and overview

1.2. 9 to 12% Cr steels

1.3. Austenitic stainless steels

1.4. Fatigue of superalloys

1.5. Lifespan prediction in high-temperature fatigue

1.6. Conclusions

1.7. Acknowledgments

1.8. Bibliography

Chapter 2. Analysis of Elasto-plastic Strains and Stresses Near Notches Subjected to Monotonic and Cyclic Multiaxial Loading Paths

2.1. Introduction

2.2. Multiaxial fatigue parameters

2.3. Elasto-plastic notch-tip stress-strain calculation methods

2.4. Comparison of notch stress-strain calculations with numerical data

2.5. Conclusion

2.6. Bibliography

2.7. Symbols

Chapter 3. Fatigue of Composite Materials

3.1. Introduction

3.2. Drastic differences between the fatigue of composites and metals

3.3. Notch effect on fatigue strength

3.4. Effect of a stress on composite fatigue

3.5. Fatigue after impact

3.6. Fatigue damage criteria

3.7. Conclusion

3.8. Bibliography

Chapter 4. Fatigue of Polymers and Elastomers

4.1. Introduction

4.2. Life of polymers

4.3. Crack propagation within polymers

4.4. Damaging mechanisms of polymers

4.5. Specific case of the fatigue of elastomers

4.6. The life of natural rubbers

4.7. Crack propagation in natural rubber

4.8. Propagation mechanisms of cracks in natural rubber

4.9. Multiaxial fatigue of rubbers

4.10. Cavitation of rubbers

4.11. Conclusion

4.12. Bibliography

Chapter 5. Probabilistic Design of Structures Submitted to Fatigue

5.1. Introduction

5.2. Treatment of hazard in mechanical models

5.3. Plotting probabilistic S-N curves

5.4. Probabilistic design with respect to crack initiation

5.5. Probabilistic propagation models

5.6. General conclusion

5.7. Appendix A: probability theory reminder

5.8. Bibliography

Chapter 6. Prediction of Fatigue Crack Growth within Structures

6.1. Prediction problems

6.2. Crack growth laws

6.3. Calculation of cracking variables

6.4. Resolution method of the cracking equations

6.5. New directions

6.6. Bibliography

List of Authors

Index

First published 2011 in Great Britain and the United States by ISTE Ltd and John Wiley & Sons, Inc. Adapted and updated from Fatigue des matériaux et des structures 3 published 2009 in France by Hermes Science/Lavoisier © LAVOISIER 2009

Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the Copyright, Designs and Patents Act 1988, this publication may only be reproduced, stored or transmitted, in any form or by any means, with the prior permission in writing of the publishers, or in the case of reprographic reproduction in accordance with the terms and licenses issued by the CLA. Enquiries concerning reproduction outside these terms should be sent to the publishers at the undermentioned address:

ISTE Ltd27-37 St George’s RoadLondon SW19 4EUUKJohn Wiley & Sons, Inc.111 River StreetHoboken, NJ 07030USAwww.iste.co.ukwww.wiley.com

© ISTE Ltd 2011

The rights of Claude Bathias and André Pineau to be identified as the authors of this work have been asserted by them in accordance with the Copyright, Designs and Patents Act 1988.

Library of Congress Cataloging-in-Publication Data

Fatigue des matériaux et des structures. English

Fatigue of materials and structures : application to damage and design / edited by Claude Bathias, Andre Pineau.

p. cm.

Includes bibliographical references and index.

ISBN 978-1-84821-267-1

1. Materials--Fatigue. I. Bathias, Claude. II. Pineau, A. (André) III. Title.

TA418.38.F3713 2010

620.1'126--dc22

2010040728

British Library Cataloguing-in-Publication Data

A CIP record for this book is available from the British Library

ISBN 978-1-84821-267-1

Foreword

This book on fatigue, combined with two other recent publications edited by Claude Bathias and André Pineau1, are the latest in a tradition that traces its origins back to a summer school held at Sherbrooke University in Quebec in the summer of 1978 which was organized by Professors Claude Bathias (then at the University of Technology of Compiegne, France) and Jean Pierre Bailon of Ecole Polytechnique, Montreal, Quebec. This meeting was held under the auspices of a program of cultural and scientific exchanges between France and Quebec. As one of the participants in this meeting, I was struck by the fact that virtually all of the presentations provided a tutorial background and an in-depth review of the fundamental and practical aspects of the field as well as a discussion of recent developments. The success of this summer school led to the decision that it would be of value to make these lectures available in the form of a book which was published in 1980. This broad treatment made the book appealing to a wide audience. Indeed, within a few years, dog-eared copies of “Sherbrooke” could be found on the desks of practicing engineers, students and researchers in France and in French-speaking countries. The original book was followed by an equally successful updated version that was published in 1997 which preserved the broad appeal of the first book. This book represents a part of the continuation of the approach taken in the first two editions while providing an even more in-depth treatment of this crucial but complex subject.

It is also important to draw attention to the highly respected “French School” of fatigue which has been at the forefront in integrating the solid mechanics and materials science aspects of fatigue. This integration led to the development of a deeper fundamental understanding thereby facilitating application of this knowledge to real engineering problems from microelectronics to nuclear reactors. Most of the authors who have contributed to the current edition have worked together over the years on numerous high-profile, critical problems in the nuclear, aerospace, and power generating industries. The informal teaming over the years perfectly reflects the mechanics/materials approach and, in terms of this book, provides a remarkable degree of continuity and coherence to the overall treatment.

The approach and ambiance of the “French School” is very much in evidence in a series of bi-annual international colloquia. These colloquia are organized by a very active “fatigue commission” within the French Society of Metals and Materials (SF2M) and are held in Paris in the spring. Indeed, these meetings have contributed to an environment which fostered the publication of this series.

The first two editions (in French), while extremely well-received and influential in the French-speaking world, were never translated into English. The third edition was recently published (again in French) and has been very well received in France. Many English-speaking engineers and researchers with connections to France strongly encouraged the publication of this third edition in English. The current three books on fatigue were translated from the original four volumes in French2 in response to that strong encouragement and wide acceptance in France.

In his preface to the second edition, Prof. Francois essentially posed the question (liberally translated), “Why publish a second volume if the first does the job?” A very good question indeed! My answer would be that technological advances place increasingly severe performance demands on fatigue-limited structures. Consider, as an example, the economic, safety and environmental requirements in the aerospace industry. Improved economic performance derives from increased payloads, greater range and reduced maintenance costs. Improved safety, demanded by the public, requires improved durability and reliability. Reduced environmental impact requires efficient use of materials and reduced emission of pollutants. These requirements translate into higher operating temperatures (to increase efficiency), increased stresses (to allow for lighter structures and greater range), improved materials (to allow for higher loads and temperatures) and improved life prediction methodologies (to set safe inspection intervals). A common thread running through these demands is the necessity to develop a better understanding of fundamental fatigue damage mechanisms and more accurate life prediction methodologies (including, for example, application of advanced statistical concepts). The task of meeting these requirements will never be completed; advances in technology will require continuous improvements in materials and more accurate life prediction schemes. This notion is well illustrated in the rapidly developing field of gigacycle fatigue. The necessity to design against fatigue failure in the regime of 109 + cycles in many applications required in-depth research which in turn has called into question the old, comfortable notion of a fatigue limit at 107 cycles. New developments and approaches are an important component of this edition and are woven through all the chapters of the three books.

It is not the purpose of this preface to review all of the chapters in detail. However, some comments about the organization and over-all approach are in order. The first chapter in the first book3 provides a broad background and historical context and sets the stage for the chapters in the subsequent books. In broad outline, the experimental, physical, analytical and engineering fundamentals of fatigue are developed in this first book. However, the development is done in the context of materials used in engineering applications and numerous practical examples are provided which illustrate the emergence of new fields (e.g. gigacycle fatigue) and evolving methodologies (e.g. sophisticated statistical approaches). In the second4 and third5 books, the tools that are developed in the first book are applied to newer classes of materials such as composites and polymers and to fatigue in practical, challenging engineering applications such as high temperature fatigue, cumulative damage and contact fatigue.

These three books cover the most important fundamental and practical aspects of fatigue in a clear and logical manner and provide a sound basis that should make them as attractive to English-speaking students, practicing engineers, and researchers as they have proved to be to our French colleagues.

Stephen D. ANTOLOVICH

Professor of Materials and Mechanical EngineeringWashington State UniversityandProfessor EmeritusGeorgia Institute of Technology

December 2010

1. C. BATHIAS, A. PINEAU (eds.), Fatigue of Materials and Structures: Fundamentals, ISTE, London and John Wiley & Sons, New York, 2010.C. BATHIAS, A. PINEAU (eds.), Fatigue of Materials and Structures: Application to Design, ISTE, London and John Wiley & Sons, New York, 2011.

2. C. BATHIAS, A. PINEAU (eds.), Fatigue des matériaux et des structures, Volumes 1, 2, 3 and 4, Hermes, Paris, 2009.

3. C. BATHIAS, A. PINEAU (eds.), Fatigue of Materials and Structures: Fundamentals, ISTE, London and John Wiley & Sons, New York, 2010.

4. This book.

5. C. BATHIAS, A. PINEAU (eds.), Fatigue of Materials and Structures: Application to Design, ISTE, London and John Wiley & Sons, New York, 2011.

Chapter 1

High Temperature Fatigue1

1.1. Introduction and overview

1.1.1. Introductory remarks

It is a basic consequence of thermodynamics that the efficiency of heat engines, regardless of their type, increases with increasing temperature. In the power generation industry (nuclear industry, coal-fired and/or oil-fired plants), any increase in working temperature leads to a decrease in fuel consumption, pollution and operating costs. In the jet engine industry, increased operating temperatures lead to improved performances, such as the combinations of heavier payloads, a greater speed and a greater range.

For the power generation industry, lower fuel consumption, reduced pollution and lower costs are important. However, as operating temperatures are increased, additional problems to those encountered at lower temperatures arise. Regardless of its type, all engines have moving parts that experience variable loading during each operating cycle. In general, loading above a certain level causes microscopic rearrangements at the atomic level, which can lead to an important damage. With continued operation (i.e. cyclic loading) damage accumulates and eventually leads to the fracture of the component. This scenario can be viewed as a working definition of fatigue. Many practical and theoretical investigations have been carried out over the past two centuries to experimentally characterize failure by fatigue and to predict the lives of components subjected to fatigue loading. Wöhler [WÖH 1860], going back more than a century, demonstrated that the fatigue life of a component may be represented in terms of stress, which eventually leads to the well-known and widely used S/N curve methodology, which was discussed in Claude Bathias and André Pineau’s Fatigue of Materials and Structures: Fundamentals. Even if fundamentaland practical difficulties are still encountered using this approach, the stress-based method is applicable to this day to make preliminary life estimates of some components.

1.1.2. A little history

1.1.2.1. Effects of temperature

At higher temperatures such as those found in the power generation and jet engine industries, not only is there repeated loading, but depending on strain rates and hold times, time-dependent damage processes such as creep and environmental attack become important. Two major advances in understanding high temperature fatigue from an engineering perspective were made in the 1950s and 1960s at NASA Lewis by Manson and coworkers (see e.g. [MAN 53]) and at General Electric by Coffin and coworkers [COF 54]. The first was in terms of conceptualizing the fatigue process in a more physically acceptable, albeit very general, manner. The second major advance was associated with advances in control technology. The rapid advances in “controls” paved the way for the development of closed-loop test machines, much more reliable data, and vastly improved life prediction capabilities. These are discussed in greater detail below.