Materials and Surface Engineering in Tribology E-Book

Jamal Takadoum

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

Seitenzahl: 258

Veröffentlichungsjahr: 2013

Beschreibung

This title is designed to provide a clear and comprehensive overview of tribology. The book introduces the notion of a surface in tribology where a solid surface is described from topographical, structural, mechanical, and energetic perspectives. It also describes the principal techniques used to characterize and analyze surfaces. The title then discusses what may be called the fundamentals of tribology by introducing and describing the concepts of adhesion, friction, wear, and lubrication. The book focuses on the materials used in tribology, introducing the major classes of materials used, either in their bulk states or as coatings, including both protective layers and other coatings used for decorative purposes. Of especial importance to the tribology community are sections that provide the latest information on Nanotribology, Wear, Lubrication, and Wear-Corrosion: Tribocorrosion and Erosion-Corrosion.

Leseprobe

Table of Contents

Foreword

Preface

Chapter 1. Surfaces

1.1. Introduction

1.2. The surface state

Chapter 2. Tribology

2.1. Introduction

2.2. Elements of solid mechanics

2.3. Elements of contact mechanics

2.4. Friction

2.5. Nanotribology

2.6. Wear

2.7. Lubrication

2.8. Wear-corrosion: tribocorrosion and erosion-corrosion

Chapter 3. Materials for Tribology

3.1. Introduction

3.2. Bulk materials

3.3. Surface treatments and coatings

3.4. Hard anti-wear anddecorative coatings

3.5. Characterization of coatings :hardness, adherence and internal stresses

Bibliography

Index

First published in France in 2007 by Hermes Science/Lavoisier entitles: “Matériaux et surfaces en tribologie”

First published in Great Britain and the United States in 2008 by ISTE Ltd and John Wiley & Sons, Inc. Translated from the French by Véronique Béguin

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 Ltd 27-37 St London SW19 4EU UKwww.iste.co.ukJohn Wiley & Sons, Inc. George’s Road 111 River Street Hoboken, NJ 07030 USAwww.wiley.com

© ISTE Ltd, 2008

© LAVOISIER, 2007

The rights of Jamal Takadoum 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

Takadoum, Jamal.

Materials and surface engineering in tribology / Jamal Takadoum ; translated from the French by Véronique Béguin.

p. cm.

"Matériaux et surfaces en tribologie."

Includes bibliographical references and index.

ISBN 978-1-84821-067-7

1. Tribology. 2. Surfaces (Technology). 3. Mechanical wear. I. Title.

TJ1075.T3113 2008

621.8'9-dc22

2008037286

British Library Cataloguing-in-Publication Data A CIP record for this book is available from the British Library ISBN: 978-1-84821-067-7

In memory of Professor Pierre-Gilles de Gennes who honored me with his foreword for the original edition of this work.

A tribute to the genius of two great scientists of the 11th and 12th centuries: Ibn Al-Haytham, the optical physicist, and Al-Jazari, the mechanical engineer.

Foreword

Tribology is an old science, yet one that remains under active development. Friction between solids was first measured as early as the Renaissance by Leonardo da Vinci who discovered (and recorded in his notebooks) some extraordinary results. Leonardo’s laws were subsequently rediscovered by the Frenchman Amontons in the 18th century. However, another 150 years elapsed before they were completely understood thanks to the efforts of the English school led by David Tabor in Cambridge.

Since the early 20th century, we have learnt to reduce friction wear in engines by combining oils with an increasing range of smart additives such as surfactants and polymers. We now have a fair understanding of the adhesion and friction of a tyre on the road, even in wet conditions. We are also able to manufacture rather efficient brakes, albeit by unsophisticated techniques at times (such as with the braking of a high-speed TGV on its tracks using a sand discharge in front of the wheels).

However, new questions are emerging; for example, we poorly understand such phenomena as the onset of earthquakes. To probe surfaces in the laboratory, we have access to highly innovative instrumentation such as the force microscope. We also have powerful simulation tools. Ultimately, from the practical point of view, a whole range of new materials is now available allowing us to reduce friction while at the same time minimizing wear.

It is essential that this know-how be made available to students and practicing engineers alike. In this regard, I find the present book particularly well suited to the needs of both graduate students and professional workers in the field. I therefore wish it every success!

P.-G. De Gennes

Preface

Derived from the Greek word tribos, meaning friction, the word tribology was first used in 1966 in Great Britain to describe the scientific and technical domains focused on the study of friction, wear and lubrication.

Tribology addresses such questions as: what is the best way to reduce wear and control friction? What materials should be used? What lubricant should be chosen to protect a motor or manufacture a particular component? What surface treatment should be applied to improve the wear resistance and reliability of a mechanical system?

Despite their apparent simplicity, the problems of tribology are in fact very complex. They involve the bulk properties of materials as well as their microscopic surface characteristics and their interaction with the surrounding environment.

By providing solutions in fields as diverse as car manufacturing and medical prosthesis, tribology can have a significant economic and ecological impact. For instance, if we can reduce friction in a motor, we reduce energy consumption and limit pollution. If we can reduce the wear in a cutting tool, we both increase productivity and improve the quality of manufactured products. If we can limit ball bearing and gearbox wear, then we can increase the life-span and improve the reliability of many different mechanical systems. If we can reduce friction in an artificial hip, then we can avoid production of wear-particles that can induce inflammation and cause serious complications such as osteolysis or even loosening of the joint itself.

Because tribological phenomena are by nature complex, solving them requires a multidisciplinary approach combining techniques derived from mechanics, solid-state physics and surface chemistry. This sometimes makes it seem like a poorly defined subject, and raises a number of challenges for effective teaching. The purpose of this book is therefore to make tribology comprehensively accessible, by illustrating its principles and its applications through a variety of case studies taken from the scientific as well as the industrial domains. In both its content and structure, Materials and Surface Engineering in Tribology is designed to provide a clear, synthetic overview of the field, and therefore serve as a reference book suitable for students, researchers and engineers alike.

Materials and Surface Engineering in Tribology is divided into three chapters:

Chapter 1 introduces the notion of a surface in tribology where a solid surface is described from the topographical, structural, mechanical and energetic points of view. It also describes the principal techniques used to characterize and analyze surfaces.

Chapter 2 discusses what may be called tribology proper by introducing and describing the concepts of adhesion, friction, wear and lubrication.

Chapter 3 focuses on the materials used in tribology. We introduce the major classes of materials used, either in their bulk states or as coatings, including both hard-facing protective layers and other coatings used for decorative purposes.

Acknowledgements

I wish to express my thanks to (in alphabetical order) Patrice Berçot, Lamine Boubakar, Bernard Cretin, Patrick Delobelle, John Dudley, Joseph Gavoille, Jan Lintymer, Hamid Makich, Nicolas Martin, Christine Millot, Jean-François Pierson, Claude Roques-Carmes and Hassan Zahouani for their contributions as proofreaders, for helping with the preparation of figures or for providing resource materials.

Finally, I wish to thank the authors and publishers who granted me permission to reproduce some figures from existing publications.

– Authors: Y. Berthier (Elsevier) [BERT 88, BERT 92], H. Pastor (SIRPE) [PAST 87], S. Mischler (MRS) [BIE 00], F. Palmino (FEMTO-ST Dpt LPMO) (Figure 1.14), A.C. Van Popta and J.M. Brett (SPIE) [VANP 04].

– Publishers: EDP Sciences [ADD 06], Elsevier [ABD 06, BUL 06, BUL 90, BUR 87a, BUR 87b, CHI 96, GAV 02a, GAY 01, GROS 01, JON 84, LIM 87, LIN 03, LIN 04, NEV 99, PIL 06, PIV 94, QUI 02, TAK 87, VOE 96], CNRS Editions/Eyrolles [GEO 00], Société Française du Vide (SFV) [TER 96], Springer [TAK 94b], the American Chemical Society [MART 95] and Wiley [BRU 03].

Chapter 1

Surfaces

1.1. Introduction

The surface of a solid delimits its volume and defines the region where interactions with its environment occur.

When considering the structure of a crystalline material, the surface corresponds to a discontinuity in the periodic arrangement of atoms. The number of nearest neighbors (8 for a body-centered cubic lattice, 12 for a hexagonal close-packed or face-centered cubic lattice) is reduced for surface atoms, so that their vibrational states, inter-atomic separations and associated electronic states are very different from those of atoms within the solid’s interior [BOI 87] (see Figure 1.1).

Figure 1.1.Centered cubic lattice showing the number of nearest neighbors for an atom: a) within a solid; b) on its surface

This difference between surface atoms and volume (or bulk) atoms allows us to introduce the notions of an ideal surface and a realistic surface. An ideal surface is defined only in terms of the topmost atomic layers spanning a dimension of only several nanometers, whereas a realistic surface describes a region that extends further below the outer surface, down to depths of several microns to several tens of microns. The mechanical, physicochemical and structural properties of this region differ noticeably from those of the material’s volume as well as those of the ideal surface [PERR 87].

Because surface atoms possess a lower number of nearest neighbors, they are involved in a smaller number of bonds and thus experience an asymmetric force field. Indeed, these atoms interact only with other surface atoms and atoms situated within the solid’s interior. This results in a certain number of dangling bonds, directed towards the exterior of the solid, which allow the solid to interact with its environment through the establishment of bonds aiming to re-establish the surface atoms’ equilibrium.