Materials Science and Engineering

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Materials Science and Engineering An Introduction

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John Wiley & Sons, Inc.

Materials Science and Engineering

An Introduction

William D. Callister, Jr.

Department of Metallurgical Engineering The University of Utah

with special contributions by David G. Rethwisch

The University of Iowa

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Front Cover: A unit cell for diamond (blue-gray spheres represent carbon atoms), which is positioned above the temperature-versus-logarithm pressure phase diagram for carbon; highlighted in blue is the region for which diamond is the stable phase.

Back Cover: Atomic structure for graphite; here the gray spheres depict carbon atoms. The region of graphite stability is highlighted in orange on the pressure-temperature phase diagram for carbon, which is situated behind this graphite structure.

ACQUISITIONS EDITOR Joseph Hayton

MARKETING DIRECTOR Frank Lyman

SENIOR PRODUCTION EDITOR Ken Santor

SENIOR DESIGNER Kevin Murphy

COVER ART Roy Wiemann

TEXT DESIGN Michael Jung

SENIOR ILLUSTRATION EDITOR Anna Melhorn

COMPOSITOR Techbooks/GTS, York, PA

ILLUSTRATION STUDIO Techbooks/GTS, York, PA

This book was set in 10/12 Times Ten by Techbooks/GTS, York, PA and printed and bound by Quebecor Versailles. The cover was printed by Quebecor.

This book is printed on acid free paper.

Copyright © 2007 John Wiley & Sons, Inc. All rights reserved.

No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (508)750-8400, fax (508)750-4470. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 605 Third Avenue, New York, NY 10158-0012, (212) 850-6011, fax (212) 850-6008, E-Mail: PERMREQ@WILEY.COM.

To order books or for customer service please call 1(800)225-5945.

Library of Congress Cataloging-in-Publication Data Callister, William D., 1940-

Materials science and engineering : an introduction / William D. Callister, Jr.—7th ed.

p. cm.

Includes bibliographical references and index.

ISBN-13: 978-0-471-73696-7 (cloth) ISBN-10: 0-471-73696-1 (cloth)

1. Materials. I. Title.

TA403.C23 2007 620.1’1—dc22

2005054228 Printed in the United States of America

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Dedicated to

my colleagues and friends in Brazil and Spain

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Contents

LIST OFSYMBOLS xxiii 1. Introduction 1

Learning Objectives 2 1.1 Historical Perspective 2

1.2 Materials Science and Engineering 3

1.3 Why Study Materials Science and Engineering? 5 1.4 Classification of Materials 5

1.5 Advanced Materials 11 1.6 Modern Materials’ Needs 12

References 13

2. Atomic Structure and Interatomic Bonding 15 Learning Objectives 16

2.1 Introduction 16 ATOMICSTRUCTURE 16 2.2 Fundamental Concepts 16 2.3 Electrons in Atoms 17 2.4 The Periodic Table 23

ATOMICBONDING INSOLIDS 24 2.5 Bonding Forces and Energies 24 2.6 Primary Interatomic Bonds 26

2.7 Secondary Bonding or van der Waals Bonding 30 2.8 Molecules 32

Summary 34

Important Terms and Concepts 34 References 35

Questions and Problems 35

3. The Structure of Crystalline Solids 38 Learning Objectives 39

3.1 Introduction 39 CRYSTALSTRUCTURES 39 3.2 Fundamental Concepts 39 3.3 Unit Cells 40

3.4 Metallic Crystal Structures 41 3.5 Density Computations 45 3.6 Polymorphism and Allotropy 46

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3.7 Crystal Systems 46

CRYSTALLOGRAPHICPOINTS, DIRECTIONS, AND

PLANES 49

3.8 Point Coordinates 49

3.9 Crystallographic Directions 51 3.10 Crystallographic Planes 55 3.11 Linear and Planar Densities 60 3.12 Close-Packed Crystal Structures 61

CRYSTALLINE ANDNONCRYSTALLINE

MATERIALS 63 3.13 Single Crystals 63

3.14 Polycrystalline Materials 64 3.15 Anisotropy 64

3.16 X-Ray Diffraction: Determination of Crystal Structures 66

3.17 Noncrystalline Solids 71 Summary 72

Important Terms and Concepts 73 References 73

Questions and Problems 74

4. Imperfections in Solids 80 Learning Objectives 81 4.1 Introduction 81

POINTDEFECTS 81

4.2 Vacancies and Self-Interstitials 81 4.3 Impurities in Solids 83

4.4 Specification of Composition 85 MISCELLANEOUSIMPERFECTIONS 88 4.5 Dislocations–Linear Defects 88 4.6 Interfacial Defects 92

4.7 Bulk or Volume Defects 96 4.8 Atomic Vibrations 96

MICROSCOPICEXAMINATION 97 4.9 General 97

4.10 Microscopic Techniques 98 4.11 Grain Size Determination 102

Summary 104

Important Terms and Concepts 105 References 105

Questions and Problems 106 Design Problems 108

5. Diffusion 109

Learning Objectives 110 5.1 Introduction 110

5.2 Diffusion Mechanisms 111 5.3 Steady-State Diffusion 112

5.4 Nonsteady-State Diffusion 114 5.5 Factors That Influence Diffusion 118 5.6 Other Diffusion Paths 125

Summary 125

Important Terms and Concepts 126 References 126

Questions and Problems 126 Design Problems 129

6. Mechanical Properties of Metals 131 Learning Objectives 132

6.1 Introduction 132

6.2 Concepts of Stress and Strain 133 ELASTICDEFORMATION 137

6.3 Stress-Strain Behavior 137 6.4 Anelasticity 140

6.5 Elastic Properties of Materials 141 PLASTICDEFORMATION 143

6.6 Tensile Properties 144 6.7 True Stress and Strain 151 6.8 Elastic Recovery after Plastic

Deformation 154

6.9 Compressive, Shear, and Torsional Deformation 154

6.10 Hardness 155

PROPERTYVARIABILITY ANDDESIGN/SAFETY

FACTORS 161

6.11 Variability of Material Properties 161 6.12 Design/Safety Factors 163

Summary 165

Important Terms and Concepts 166 References 166

Questions and Problems 166 Design Problems 172

7. Dislocations and Strengthening Mechanisms 174

Learning Objectives 175 7.1 Introduction 175

DISLOCATIONS ANDPLASTIC

DEFORMATION 175 7.2 Basic Concepts 175

7.3 Characteristics of Dislocations 178 7.4 Slip Systems 179

7.5 Slip in Single Crystals 181

7.6 Plastic Deformation of Polycrystalline Materials 185

7.7 Deformation by Twinning 185 xvi Contents

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MECHANISMS OFSTRENGTHENING INMETALS 188

7.8 Strengthening by Grain Size Reduction 188

7.9 Solid-Solution Strengthening 190 7.10 Strain Hardening 191

RECOVERY, RECRYSTALLIZATION, ANDGRAIN

GROWTH 194 7.11 Recovery 195 7.12 Recrystallization 195 7.13 Grain Growth 200

Summary 201

Important Terms and Concepts 202 References 202

Questions and Problems 202 Design Problems 206

8. Failure 207

Learning Objectives 208 8.1 Introduction 208

FRACTURE 208

8.2 Fundamentals of Fracture 208 8.3 Ductile Fracture 209

8.4 Brittle Fracture 211

8.5 Principles of Fracture Mechanics 215 8.6 Impact Fracture Testing 223

FATIGUE 227 8.7 Cyclic Stresses 228 8.8 The S–N Curve 229

8.9 Crack Initiation and Propagation 232 8.10 Factors That Affect Fatigue Life 234 8.11 Environmental Effects 237

CREEP 238

8.12 Generalized Creep Behavior 238 8.13 Stress and Temperature Effects 239 8.14 Data Extrapolation Methods 241 8.15 Alloys for High-Temperature

Use 242 Summary 243

Important Terms and Concepts 245 References 246

Questions and Problems 246 Design Problems 250

9. Phase Diagrams 252 Learning Objectives 253 9.1 Introduction 253

DEFINITIONS ANDBASICCONCEPTS 253

Contents xvii 9.2 Solubility Limit 254

9.3 Phases 254

9.4 Microstructure 255 9.5 Phase Equilibria 255

9.6 One-Component (or Unary) Phase Diagrams 256

BINARYPHASEDIAGRAMS 258 9.7 Binary Isomorphous Systems 258 9.8 Interpretation of Phase Diagrams 260 9.9 Development of Microstructure in

Isomorphous Alloys 264

9.10 Mechanical Properties of Isomorphous Alloys 268

9.11 Binary Eutectic Systems 269 9.12 Development of Microstructure in

Eutectic Alloys 276

9.13 Equilibrium Diagrams Having Intermediate Phases or Compounds 282

9.14 Eutectic and Peritectic Reactions 284 9.15 Congruent Phase

Transformations 286 9.16 Ceramic and Ternary Phase

Diagrams 287

9.17 The Gibbs Phase Rule 287 THEIRON–CARBONSYSTEM 290

9.18 The Iron–Iron Carbide (Fe–Fe3C) Phase Diagram 290

9.19 Development of Microstructure in Iron–Carbon Alloys 293

9.20 The Influence of Other Alloying Elements 301

Summary 302

Important Terms and Concepts 303 References 303

Questions and Problems 304

10. Phase Transformations in Metals:

Development of Microstructure and Alteration of Mechanical Properties 311

Learning Objectives 312 10.1 Introduction 312

PHASETRANSFORMATIONS 312 10.2 Basic Concepts 312 10.3 The Kinetics of Phase

Transformations 313

10.4 Metastable versus Equilibrium States 324

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xviii Contents

MICROSTRUCTURAL ANDPROPERTYCHANGES IN

IRON–CARBONALLOYS 324

10.5 Isothermal Transformation Diagrams 325 10.6 Continuous Cooling Transformation

Diagrams 335

10.7 Mechanical Behavior of Iron–Carbon Alloys 339

10.8 Tempered Martensite 343

10.9 Review of Phase Transformations and Mechanical Properties for Iron–Carbon Alloys 346

Summary 350

Important Terms and Concepts 351 References 352

Questions and Problems 352 Design Problems 356

11. Applications and Processing of Metal Alloys 358

Learning Objectives 359 11.1 Introduction 359

TYPES OFMETALALLOYS 359 11.2 Ferrous Alloys 359 11.3 Nonferrous Alloys 372

FABRICATION OFMETALS 382 11.4 Forming Operations 383 11.5 Casting 384

11.6 Miscellaneous Techniques 386 THERMALPROCESSING OFMETALS 387 11.7 Annealing Processes 388

11.8 Heat Treatment of Steels 390 11.9 Precipitation Hardening 402

Summary 407

Important Terms and Concepts 409 References 409

Questions and Problems 410 Design Problems 411

12. Structures and Properties of Ceramics 414

Learning Objectives 415 12.1 Introduction 415

CERAMICSTRUCTURES 415 12.2 Crystal Structures 415 12.3 Silicate Ceramics 426 12.4 Carbon 430

12.5 Imperfections in Ceramics 434 12.6 Diffusion in Ionic Materials 438

12.7 Ceramic Phase Diagrams 439 MECHANICALPROPERTIES 442 12.8 Brittle Fracture of Ceramics 442 12.9 Stress–Strain Behavior 447 12.10 Mechanisms of Plastic

Deformation 449

12.11 Miscellaneous Mechanical Considerations 451 Summary 453

Important Terms and Concepts 454 References 454

Questions and Problems 455 Design Problems 459

13. Applications and Processing of Ceramics 460

Learning Objectives 461 13.1 Introduction 461

TYPES ANDAPPLICATIONS OF

CERAMICS 461 13.2 Glasses 461

13.3 Glass–Ceramics 462 13.4 Clay Products 463 13.5 Refractories 464 13.6 Abrasives 466 13.7 Cements 467

13.8 Advanced Ceramics 468 FABRICATION ANDPROCESSING OF

CERAMICS 471

13.9 Fabrication and Processing of Glasses and Glass–Ceramics 471

13.10 Fabrication and Processing of Clay Products 476

13.11 Powder Pressing 481 13.12 Tape Casting 484

Summary 484

Important Terms and Concepts 486 References 486

Questions and Problems 486 Design Problem 488

14. Polymer Structures 489 Learning Objectives 490 14.1 Introduction 490

14.2 Hydrocarbon Molecules 490 14.3 Polymer Molecules 492 14.4 The Chemistry of Polymer

Molecules 493 14.5 Molecular Weight 497

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Contents xix 14.6 Molecular Shape 500

14.7 Molecular Structure 501 14.8 Molecular Configurations 503 14.9 Thermoplastic and Thermosetting

Polymers 506 14.10 Copolymers 507

14.11 Polymer Crystallinity 508 14.12 Polymer Crystals 512 14.13 Defects in Polymers 514

14.14 Diffusion in Polymeric Materials 515 Summary 517

Important Terms and Concepts 519 References 519

Questions and Problems 519

15. Characteristics, Applications, and Processing of Polymers 523

Learning Objectives 524 15.1 Introduction 524

MECHANICALBEHAVIOR OFPOLYMERS 524 15.2 Stress–Strain Behavior 524

15.3 Macroscopic Deformation 527 15.4 Viscoelastic Deformation 527 15.5 Fracture of Polymers 532 15.6 Miscellaneous Mechanical

Characteristics 533

MECHANISMS OFDEFORMATION AND FOR

STRENGTHENING OFPOLYMERS 535 15.7 Deformation of Semicrystalline

Polymers 535

15.8 Factors That Influence the Mechanical Properties of Semicrystalline

Polymers 538

15.9 Deformation of Elastomers 541 CRYSTALLIZATION, MELTING, ANDGLASS

TRANSITIONPHENOMENA INPOLYMERS 544 15.10 Crystallization 544

15.11 Melting 545

15.12 The Glass Transition 545 15.13 Melting and Glass Transition

Temperatures 546

15.14 Factors That Influence Melting and Glass Transition Temperatures 547

POLYMERTYPES 549 15.15 Plastics 549 15.16 Elastomers 552 15.17 Fibers 554

15.18 Miscellaneous Applications 555 15.19 Advanced Polymeric Materials 556

POLYMERSYNTHESIS ANDPROCESSING 560 15.20 Polymerization 561

15.21 Polymer Additives 563

15.22 Forming Techniques for Plastics 565 15.23 Fabrication of Elastomers 567 15.24 Fabrication of Fibers and Films 568

Summary 569

Important Terms and Concepts 571 References 571

Questions and Problems 572 Design Questions 576

16. Composites 577

Learning Objectives 578 16.1 Introduction 578

PARTICLE-REINFORCEDCOMPOSITES 580 16.2 Large-Particle Composites 580 16.3 Dispersion-Strengthened

Composites 584

FIBER-REINFORCEDCOMPOSITES 585 16.4 Influence of Fiber Length 585 16.5 Influence of Fiber Orientation and

Concentration 586 16.6 The Fiber Phase 595 16.7 The Matrix Phase 596

16.8 Polymer-Matrix Composites 597 16.9 Metal-Matrix Composites 603 16.10 Ceramic-Matrix Composites 605 16.11 Carbon–Carbon Composites 606 16.12 Hybrid Composites 607

16.13 Processing of Fiber-Reinforced Composites 607

STRUCTURALCOMPOSITES 610 16.14 Laminar Composites 610 16.15 Sandwich Panels 611

Summary 613

Important Terms and Concepts 615 References 616

Questions and Problems 616 Design Problems 619

17. Corrosion and Degradation of Materials 621

Learning Objectives 622 17.1 Introduction 622

CORROSION OFMETALS 622

17.2 Electrochemical Considerations 623 17.3 Corrosion Rates 630

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17.4 Prediction of Corrosion Rates 631 17.5 Passivity 638

17.6 Environmental Effects 640 17.7 Forms of Corrosion 640 17.8 Corrosion Environments 648 17.9 Corrosion Prevention 649 17.10 Oxidation 651

CORROSION OFCERAMICMATERIALS 654 DEGRADATION OFPOLYMERS 655 17.11 Swelling and Dissolution 655 17.12 Bond Rupture 657

17.13 Weathering 658 Summary 659

Important Terms and Concepts 660 References 661

Questions and Problems 661 Design Problems 644

18. Electrical Properties 665 Learning Objectives 666 18.1 Introduction 666

ELECTRICALCONDUCTION 666 18.2 Ohm’s Law 666

18.3 Electrical Conductivity 667

18.4 Electronic and Ionic Conduction 668 18.5 Energy Band Structures in

Solids 668

18.6 Conduction in Terms of Band and Atomic Bonding Models 671 18.7 Electron Mobility 673

18.8 Electrical Resistivity of Metals 674 18.9 Electrical Characteristics of Commercial

Alloys 677

SEMICONDUCTIVITY 679

18.10 Intrinsic Semiconduction 679 18.11 Extrinsic Semiconduction 682

18.12 The Temperature Dependence of Carrier Concentration 686

18.13 Factors That Affect Carrier Mobility 688 18.14 The Hall Effect 692

18.15 Semiconductor Devices 694

ELECTRICALCONDUCTION INIONICCERAMICS AND INPOLYMERS 700

18.16 Conduction in Ionic Materials 701 18.17 Electrical Properties of Polymers 701

DIELECTRICBEHAVIOR 702 18.18 Capacitance 703

18.19 Field Vectors and Polarization 704

18.20 Types of Polarization 708

18.21 Frequency Dependence of the Dielectric Constant 709

18.22 Dielectric Strength 711 18.23 Dielectric Materials 711

OTHERELECTRICALCHARACTERISTICS OF

MATERIALS 711 18.24 Ferroelectricity 711 18.25 Piezoelectricity 712

Summary 713

Important Terms and Concepts 715 References 715

Questions and Problems 716 Design Problems 720

19. Thermal Properties W1 Learning Objectives W2 19.1 Introduction W2

19.2 Heat Capacity W2 19.3 Thermal Expansion W4 19.4 Thermal Conductivity W7 19.5 Thermal Stresses W12

Summary W14

Important Terms and Concepts W15 References W15

Questions and Problems W15 Design Problems W17

20. Magnetic Properties W19 Learning Objectives W20 20.1 Introduction W20 20.2 Basic Concepts W20 20.3 Diamagnetism and

Paramagnetism W24 20.4 Ferromagnetism W26 20.5 Antiferromagnetism and

Ferrimagnetism W28

20.6 The Influence of Temperature on Magnetic Behavior W32 20.7 Domains and Hysteresis W33 20.8 Magnetic Anisotropy W37 20.9 Soft Magnetic Materials W38 20.10 Hard Magnetic Materials W41 20.11 Magnetic Storage W44

20.12 Superconductivity W47 Summary W50

Important Terms and Concepts W52 References W52

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Contents xxi 21. Optical Properties W57

Learning Objectives W58 21.1 Introduction W58

BASICCONCEPTS W58

21.2 Electromagnetic Radiation W58 21.3 Light Interactions with Solids W60 21.4 Atomic and Electronic

Interactions W61

OPTICALPROPERTIES OFMETALS W62 OPTICALPROPERTIES OFNONMETALS W63 21.5 Refraction W63

21.6 Reflection W65 21.7 Absorption W65 21.8 Transmission W68 21.9 Color W69

21.10 Opacity and Translucency in Insulators W71

APPLICATIONS OFOPTICALPHENOMENA W72 21.11 Luminescence W72

21.12 Photoconductivity W72 21.13 Lasers W75

21.14 Optical Fibers in Communications W79 Summary W82

Important Terms and Concepts W83 References W84

Questions and Problems W84 Design Problem W85

22. Materials Selection and Design Considerations W86

Learning Objectives W87 22.1 Introduction W87

MATERIALSSELECTION FOR ATORSIONALLY

STRESSEDCYLINDRICALSHAFT W87 22.2 Strength Considerations–Torsionally

Stressed Shaft W88

22.3 Other Property Considerations and the Final Decision W93

AUTOMOTIVEVALVESPRING W94

22.4 Mechanics of Spring Deformation W94 22.5 Valve Spring Design and Material

Requirements W95

22.6 One Commonly Employed Steel Alloy W98

FAILURE OF ANAUTOMOBILEREAR AXLE W101

22.7 Introduction W101

22.8 Testing Procedure and Results W102 22.9 Discussion W108

ARTIFICIALTOTALHIPREPLACEMENT W108 22.10 Anatomy of the Hip Joint W108 22.11 Material Requirements W111 22.12 Materials Employed W112

CHEMICALPROTECTIVECLOTHING W115 22.13 Introduction W115

22.14 Assessment of CPC Glove Materials to Protect Against Exposure to Methylene Chloride W115

MATERIALS FORINTEGRATEDCIRCUIT

PACKAGES W119 22.15 Introduction W119

22.16 Leadframe Design and Materials W120 22.17 Die Bonding W121

22.18 Wire Bonding W124

22.19 Package Encapsulation W125 22.20 Tape Automated Bonding W127

Summary W129 References W130

Design Questions and Problems W131

23. Economic, Environmental, and Societal Issues in Materials Science and Engineering W135

Learning Objectives W136 23.1 Introduction W136

ECONOMICCONSIDERATIONS W136 23.2 Component Design W137 23.3 Materials W137

23.4 Manufacturing Techniques W137 ENVIRONMENTAL ANDSOCIETAL

CONSIDERATIONS W137

23.5 Recycling Issues in Materials Science and Engineering W140

Summary W143 References W143 Design Question W144

Appendix A The International System of Units A1

Appendix B Properties of Selected Engineering Materials A3 B.1 Density A3

B.2 Modulus of Elasticity A6 B.3 Poisson’s Ratio A10

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xxii Contents

B.4 Strength and Ductility A11

B.5 Plane Strain Fracture Toughness A16 B.6 Linear Coefficient of Thermal

Expansion A17

B.7 Thermal Conductivity A21 B.8 Specific Heat A24

B.9 Electrical Resistivity A26 B.10 Metal Alloy Compositions A29 Appendix C Costs and Relative Costs for Selected Engineering Materials A31 Appendix D Repeat Unit Structures for Common Polymers A37

Appendix E Glass Transition and Melting Temperatures for Common Polymeric Materials A41

Glossary G0

Answers to Selected Problems S1 Index I1

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ix

Preface

I

n this Seventh Edition I have retained the objectives and approaches for teaching materials science and engineering that were presented in previous editions.The first, and primary, objective is to present the basic fundamentals on a level appropriate for university/college students who have completed their freshmen calculus, chemistry, and physics courses. In order to achieve this goal, I have endeavored to use terminology that is familiar to the student who is encountering the discipline of materials science and engineering for the first time, and also to define and explain all unfamiliar terms.

The second objective is to present the subject matter in a logical order, from the simple to the more complex. Each chapter builds on the content of previous ones.

The third objective, or philosophy, that I strive to maintain throughout the text is that if a topic or concept is worth treating, then it is worth treating in sufficient detail and to the extent that students have the opportunity to fully understand it without having to consult other sources; also, in most cases, some practical relevance is provided. Discussions are intended to be clear and concise and to begin at appropriate levels of understanding.

The fourth objective is to include features in the book that will expedite the learning process. These learning aids include:

• Numerous illustrations, now presented in full color, and photographs to help visualize what is being presented;

• Learning objectives;

• “Why Study . . .” and “Materials of Importance” items that provide rele- vance to topic discussions;

• Key terms and descriptions of key equations highlighted in the margins for quick reference;

• End-of-chapter questions and problems;

• Answers to selected problems;

• A glossary, list of symbols, and references to facilitate understanding the subject matter.

The fifth objective is to enhance the teaching and learning process by using the newer technologies that are available to most instructors and students of engineering today.

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Several important changes have been made with this Seventh Edition. One of the most significant is the incorporation of a number of new sections, as well

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as revisions/amplifications of other sections. New sections/discussions are as follows:

• One-component (or unary) phase diagrams (Section 9.6)

• Compacted graphite iron (in Section 11.2, “Ferrous Alloys”)

• Lost foam casting (in Section 11.5, “Casting”)

• Temperature dependence of Frenkel and Schottky defects (in Section 12.5,

“Imperfections in Ceramics”)

• Fractography of ceramics (in Section 12.8, “Brittle Fracture of Ceramics”)

• Crystallization of glass-ceramics, in terms of isothermal transformation and continuous cooling transformation diagrams (in Section 13.3,

“Glass-Ceramics”)

• Permeability in polymers (in Section 14.14, “Diffusion in Polymeric Materials”)

• Magnetic anisotropy (Section 20.8)

• A new case study on chemical protective clothing (Sections 22.13 and 22.14).

Those sections that have been revised/amplified, include the following:

• Treatments in Chapter 1 (“Introduction”) on the several material types have been enlarged to include comparisons of various property values (as bar charts).

• Expanded discussions on crystallographic directions and planes in hexagonal crystals (Sections 3.9 and 3.10); also some new related homework problems.

• Comparisons of (1) dimensional size ranges for various structural elements, and (2) resolution ranges for the several microscopic examination tech- niques (in Section 4.10, “Microscopic Techniques”).

• Updates on hardness testing techniques (Section 6.10).

• Revised discussion on the Burgers vector (Section 7.4).

• New discussion on why recrystallization temperature depends on the purity of a metal (Section 7.12).

• Eliminated some detailed discussion on fracture mechanics—i.e., used

“Concise Version” from sixth edition (Section 8.5).

• Expanded discussion on nondestructive testing (Section 8.5).

• Used Concise Version (from sixth edition) of discussion on crack initiation and propagation (for fatigue, Section 8.9), and eliminated section on crack propagation rate.

• Refined terminology and representations of polymer structures (Sections 14.3 through 14.8).

• Eliminated discussion on fringed-micelle model (found in Section 14.12 of the sixth edition).

• Enhanced discussion on defects in polymers (Section 14.13).

• Revised the following sections in Chapter 15 (“Characteristics, Applica- tions, and Processing of Polymers”): fracture of polymers (Section 15.5), deformation of semicrystalline polymers (Section 15.7), adhesives (in Section 15.18), polymerization (Section 15.20), and fabrication of fibers and films (Section 15.24).

• Revised treatment of polymer degradation (Section 17.12).

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Materials of Importance

One new feature that has been incorporated in this edition is “Materials of Im- portance” pieces; in these we discuss familiar and interesting materials/applications of materials. These pieces lend some relevance to topical coverage, are found in most chapters in the book, and include the following:

• Carbonated Beverage Containers

• Water (Its Volume Expansion Upon Freezing)

• Tin (Its Allotropic Transformation)

• Catalysts (and Surface Defects)

• Aluminum for Integrated Circuit Interconnects

• Lead-Free Solders

• Shape-Memory Alloys

• Metal Alloys Used for Euro Coins

• Carbon Nanotubes

• Piezoelectric Ceramics

• Shrink-Wrap Polymer Films

• Phenolic Billiard Balls

• Nanocomposites in Tennis Balls

• Aluminum Electrical Wires

• Invar and Other Low-Expansion Alloys

• An Iron-Silicon Alloy That is Used in Transformer Cores

• Light-Emitting Diodes Concept Check

Another new feature included in this seventh edition is what we call a “Concept Check,” a question that tests whether or not a student understands the subject mat- ter on a conceptual level. Concept check questions are found within most chap- ters; many of them appeared in the end-of-chapter Questions and Problems sections of the previous edition. Answers to these questions are on the book’s Web site, www.wiley.com/college/callister(Student Companion Site).

And, finally, for each chapter, both the Summary and the Questions and Prob- lems are organized by section; section titles precede their summaries and ques- tions/problems.

Format Changes

There are several other major changes from the format of the sixth edition. First of all, no CD-ROM is packaged with the in-print text; all electronic components are found on the book’s Web site (www.wiley.com/college/callister). This includes the last five chapters in the book—viz. Chapter 19, “Thermal Properties;” Chapter 20,

“Magnetic Properties;” Chapter 21, “Optical Properties;” Chapter 22, “Materials Selection and Design Considerations;” and Chapter 23, “Economic, Environmental, and Societal Issues in Materials Science and Engineering.” These chapters are in Adobe Acrobat®pdf format and may be downloaded.

Furthermore, only complete chapters appear on the Web site (rather than se- lected sections for some chapters per the sixth edition). And, in addition, for all sec- tions of the book there is only one version—for the two-version sections of the sixth edition, in most instances, the detailed ones have been retained.

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Six case studies have been relegated to Chapter 22, “Materials Selection and Design Considerations,” which are as follows:

• Materials Selection for a Torsionally Stressed Cylindrical Shaft

• Automobile Valve Spring

• Failure of an Automobile Rear Axle

• Artificial Total Hip Replacement

• Chemical Protective Clothing

• Materials for Integrated Circuit Packages

References to these case studies are made in the left-page margins at appropriate locations in the other chapters. All but “Chemical Protective Clothing” appeared in the sixth edition; it replaces the “Thermal Protection System on the Space Shuttle Orbiter” case study.

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Also found on the book’s Web site (under “Student Companion Site”) are several important instructional elements for the student that complement the text; these include the following:

1. VMSE: Virtual Materials Science and Engineering. This is essentially the same software program that accompanied the previous edition, but now browser- based for easier use on a wider variety of computer platforms. It consists of in- teractive simulations and animations that enhance the learning of key concepts in materials science and engineering, and, in addition, a materials properties/cost database. Students can access VMSE via the registration code included with all new copies.

Throughout the book, whenever there is some text or a problem that is sup- plemented by VMSE, a small “icon” that denotes the associated module is in- cluded in one of the margins. These modules and their corresponding icons are as follows:

Metallic Crystal Structures

Phase Diagrams and Crystallography

Ceramic Crystal Structures Diffusion Repeat Unit and PolymerStructures Tensile Tests

Dislocations Solid-Solution Strengthening

2. Answers to the Concept Check questions.

3. Direct access to online self-assessment exercises. This is a Web-based assess- ment program that contains questions and problems similar to those found in the text; these problems/questions are organized and labeled according to textbook sections. An answer/solution that is entered by the user in response to a ques- tion/problem is graded immediately, and comments are offered for incorrect re- sponses. The student may use this electronic resource to review course material, and to assess his/her mastery and understanding of topics covered in the text.

xii Preface

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4. Additional Web resources, which include the following:

• Index of Learning Styles. Upon answering a 44-item questionnaire, a user’s learning style preference (i.e., the manner in which information is assimi- lated and processed) is assessed.

• Extended Learning Objectives. A more extensive list of learning objectives than is provided at the beginning of each chapter.

• Links to Other Web Resources. These links are categorized according to general Internet, software, teaching, specific course content/activities, and materials databases.

I

NSTRUCTORS

’ R

ESOURCES

The “Instructor Companion Site” (www.wiley.com/college/callister) is available for instructors who have adopted this text. Resources that are available include the following:

1. Detailed solutions of all end-of-chapter questions and problems (in both Microsoft Word®and Adobe Acrobat®PDF formats).

2. Photographs, illustrations, and tables that appear in the book (in PDF and JPEG formats); an instructor can print them for handouts or prepare transparen- cies in his/her desired format.

3. A set of PowerPoint®lecture slides developed by Peter M. Anderson (The Ohio State University) and David G. Rethwisch (The University of Iowa). These slides follow the flow of topics in the text, and include materials from the text and other sources as well as illustrations and animations. Instructors may use the slides as is or edit them to fit their teaching needs.

4. A list of classroom demonstrations and laboratory experiments that portray phenomena and/or illustrate principles that are discussed in the book; references are also provided that give more detailed accounts of these demonstrations.

5. Suggested course syllabi for the various engineering disciplines.

WileyPLUS

WileyPLUSgives you, the instructor, the technology to create an environment where students reach their full potential and experience academic success that will last a lifetime! With WileyPLUS, students will come to class better prepared for your lec- tures, get immediate feedback and context-sensitive help on assignments and quizzes, and have access to a full range of interactive learning resources including a com- plete online version of their text. WileyPLUS gives you a wealth of presentation and preparation tools, easy-to-navigate assessment tools including an online gradebook, and a complete system to administer and manage your course exactly as you wish.

Contact your local Wiley representative for details on how to set up your WileyPLUS course, or visit the website at www.wiley.com/college/wileyplus.

F

EEDBACK

I have a sincere interest in meeting the needs of educators and students in the materials science and engineering community, and therefore would like to solicit feedback on this seventh edition. Comments, suggestions, and criticisms may be submitted to me via e-mail at the following address: billcallister@comcast.net.

A

CKNOWLEDGMENTS

Appreciation is expressed to those who have made contributions to this edition.

I am especially indebted to David G. Rethwisch, who, as a special contributor, Preface xiii

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provided invaluable assistance in updating and upgrading important material in a number of chapters. In addition, I sincerely appreciate Grant E. Head’s expert pro- gramming skills, which he used in developing the Virtual Materials Science and En- gineeringsoftware. Important input was also furnished by Carl Wood of Utah State University and W. Roger Cannon of Rutgers University, to whom I also give thanks.

In addition, helpful ideas and suggestions have been provided by the following:

xiv Preface

Tarek Abdelsalam, East Carolina University Keyvan Ahdut, University of the District of

Columbia

Mark Aindow, University of Connecticut (Storrs) Pranesh Aswath, University of Texas at Arlington Mir Atiqullah, St. Louis University

Sayavur Bakhtiyarov, Auburn University Kristen Constant, Iowa State University Raymond Cutler, University of Utah Janet Degrazia, University of Colorado

Mark DeGuire, Case Western Reserve University Timothy Dewhurst, Cedarville University

Amelito Enriquez, Canada College Jeffrey Fergus, Auburn University

Victor Forsnes, Brigham Young University (Idaho) Paul Funkenbusch, University of Rochester Randall German, Pennsylvania State University Scott Giese, University of Northern Iowa Brian P. Grady, University of Oklahoma Theodore Greene, Wentworth Institute of

Technology

Todd Gross, University of New Hampshire Jamie Grunlan, Texas A & M University Masanori Hara, Rutgers University

Russell Herlache, Saginaw Valley State University Susan Holl, California State University

(Sacramento)

Zhong Hu, South Dakota State University Duane Jardine, University of New Orleans Jun Jin, Texas A & M University at Galveston Paul Johnson, Grand Valley State University Robert Johnson, University of Texas at Arlington Robert Jones, University of Texas (Pan American)

Maureen Julian, Virginia Tech James Kawamoto, Mission College

Edward Kolesar, Texas Christian University Stephen Krause, Arizona State University (Tempe) Robert McCoy, Youngstown State University Scott Miller, University of Missouri (Rolla) Devesh Misra, University of Louisiana at

Lafayette

Angela L. Moran, U.S. Naval Academy James Newell, Rowan University Toby Padilla, Colorado School of Mines Timothy Raymond, Bucknell University Alessandro Rengan, Central State University Bengt Selling, Royal Institute of Technology

(Stockholm, Sweden)

Ismat Shah, University of Delaware

Patricia Shamamy, Lawrence Technological University

Adel Sharif, California State University at Los Angeles

Susan Sinnott, University of Florida Andrey Soukhojak, Lehigh University Erik Spjut, Harvey Mudd College

David Stienstra, Rose-Hulman Institute of Technology

Alexey Sverdlin, Bradley University Dugan Um, Texas State University

Raj Vaidyanatha, University of Central Florida Kant Vajpayee, University of Southern Mississippi Kumar Virwani, University of Arkansas

(Fayetteville)

Mark Weaver, University of Alabama (Tuscaloosa) Jason Weiss, Purdue University (West Lafayette) I am also indebted to Joseph P. Hayton, Sponsoring Editor, and to Kenneth Santor, Senior Production Editor at Wiley for their assistance and guidance on this revision.

Since I undertook the task of writing my first text on this subject in the early- 80’s, instructors and students too numerous to mention have shared their input and contributions on how to make this work more effective as a teaching and learning tool. To all those who have helped, I express my sincere “Thanks!”

Last, but certainly not least, the continual encouragement and support of my family and friends is deeply and sincerely appreciated.

WILLIAMD. CALLISTER, JR. Salt Lake City, Utah January 2006

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T

he number of the section in which a symbol is introduced or explained is given in parentheses.

List of Symbols

A !area

Å ! angstrom unit

Ai!atomic weight of element i (2.2) APF ! atomic packing factor (3.4)

a !lattice parameter: unit cell x-axial length (3.4)

a !crack length of a surface crack (8.5) at% ! atom percent (4.4)

B !magnetic flux density (induction) (20.2)

Br!magnetic remanence (20.7) BCC ! body-centered cubic crystal

structure (3.4)

b !lattice parameter: unit cell y-axial length (3.7) b ! Burgers vector (4.5) C !capacitance (18.18)

Ci!concentration (composition) of component i in wt% (4.4) C"i!concentration (composition) of

component i in at% (4.4)

Cv, Cp!heat capacity at constant volume, pressure (19.2)

CPR ! corrosion penetration rate (17.3) CVN ! Charpy V-notch (8.6)

%CW ! percent cold work (7.10) c !lattice parameter: unit cell

z-axial length (3.7)

c !velocity of electromagnetic radia- tion in a vacuum (21.2)

D !diffusion coefficient (5.3) D !dielectric displacement (18.19)

DP !degree of polymerization (14.5) d !diameter

d !average grain diameter (7.8) dhkl!interplanar spacing for planes of

Miller indices h, k, and l (3.16) E !energy (2.5)

E !modulus of elasticity or Young’s modulus (6.3)

!electric field intensity (18.3) Ef!Fermi energy (18.5)

Eg!band gap energy (18.6) Er(t) ! relaxation modulus (15.4)

%EL ! ductility, in percent elongation (6.6)

e !electric charge per electron (18.7) e#!electron (17.2)

erf ! Gaussian error function (5.4) exp ! e, the base for natural logarithms

F !force, interatomic or mechanical (2.5, 6.3)

!Faraday constant (17.2) FCC ! face-centered cubic crystal

structure (3.4) G !shear modulus (6.3)

H !magnetic field strength (20.2) Hc!magnetic coercivity (20.7) HB ! Brinell hardness (6.10)

HCP ! hexagonal close-packed crystal structure (3.4)

HK ! Knoop hardness (6.10) HRB, HRF ! Rockwell hardness: B and F

scales (6.10) f

e

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xxiv List of Symbols

HR15N, HR45W ! superficial Rockwell hardness: 15N and 45W scales (6.10)

HV ! Vickers hardness (6.10) h !Planck’s constant (21.2) (hkl) ! Miller indices for a

crystallographic plane (3.10) I !electric current (18.2) I !intensity of electromagnetic

radiation (21.3) i !current density (17.3) iC!corrosion current density

(17.4)

J !diffusion flux (5.3)

J !electric current density (18.3) Kc!fracture toughness (8.5) KIc!plane strain fracture

toughness for mode I crack surface displacement (8.5)

k !Boltzmann’s constant (4.2) k !thermal conductivity (19.4)

l !length

lc!critical fiber length (16.4) ln ! natural logarithm

log ! logarithm taken to base 10 M !magnetization (20.2)

!polymer number-average molecular weight (14.5)

!polymer weight-average molecular weight (14.5) mol% ! mole percent

N !number of fatigue cycles (8.8) NA!Avogadro’s number (3.5)

Nf!fatigue life (8.8)

n !principal quantum number (2.3)

n !number of atoms per unit cell (3.5)

n !strain-hardening exponent (6.7)

n !number of electrons in an electrochemical reaction (17.2) Mw

Mn

n !number of conducting electrons per cubic meter (18.7)

n !index of refraction (21.5) n! !for ceramics, the number of formula units per unit cell (12.2)

ni!intrinsic carrier (electron and hole) concentration (18.10) P !dielectric polarization (18.19) P–B ratio ! Pilling–Bedworth ratio (17.10)

p !number of holes per cubic meter (18.10)

Q !activation energy

Q !magnitude of charge stored (18.18)

R !atomic radius (3.4) R !gas constant

%RA ! ductility, in percent reduction in area (6.6)

r !interatomic distance (2.5) r !reaction rate (17.3)

rA, rC!anion and cation ionic radii (12.2)

S !fatigue stress amplitude (8.8) SEM ! scanning electron

microscopy or microscope T !temperature

Tc!Curie temperature (20.6) TC!superconducting critical tem-

perature (20.12)

Tg!glass transition temperature (13.9, 15.12)

Tm!melting temperature TEM ! transmission electron

microscopy or microscope TS !tensile strength (6.6)

t !time

tr!rupture lifetime (8.12) Ur!modulus of resilience (6.6) [uvw] ! indices for a crystallographic

direction (3.9)

V !electrical potential difference (voltage) (17.2, 18.2)

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List of Symbols xxv VC!unit cell volume (3.4)

VC!corrosion potential (17.4) VH!Hall voltage (18.14)

Vi!volume fraction of phase i (9.8) v ! velocity

vol% ! volume percent

Wi!mass fraction of phase i (9.8) wt% ! weight percent (4.4)

x !length

x !space coordinate

Y !dimensionless parameter or function in fracture toughness expression (8.5) y !space coordinate

z !space coordinate

! !lattice parameter: unit cell y–z interaxial angle (3.7)

!, ", # ! phase designations

!l!linear coefficient of thermal expansion (19.3)

" !lattice parameter: unit cell x–z interaxial angle (3.7)

# !lattice parameter: unit cell x–y interaxial angle (3.7)

# !shear strain (6.2)

$ !precedes the symbol of a parameter to denote finite change

$ !engineering strain (6.2)

$ !dielectric permittivity (18.18)

$r!dielectric constant or relative permittivity (18.18)

$%s!steady-state creep rate (8.12)

$T!true strain (6.7)

% !viscosity (12.10)

% !overvoltage (17.4)

& !Bragg diffraction angle (3.16)

&D!Debye temperature (19.2) ' !wavelength of electromagnetic

radiation (3.16)

( !magnetic permeability (20.2) (B!Bohr magneton (20.2)

(r!relative magnetic permeability (20.2) (e!electron mobility (18.7)

(h!hole mobility (18.10) n !Poisson’s ratio (6.5)

n !frequency of electromagnetic radiation (21.2)

) !density (3.5)

) !electrical resistivity (18.2)

)t!radius of curvature at the tip of a crack (8.5)

* !engineering stress, tensile or compressive (6.2)

* !electrical conductivity (18.3)

** ! longitudinal strength (composite) (16.5)

*c!critical stress for crack propagation (8.5)

*fs!flexural strength (12.9)

*m!maximum stress (8.5)

*m!mean stress (8.7)

*"m!stress in matrix at composite failure (16.5)

*T!true stress (6.7)

*w!safe or working stress (6.12)

*y!yield strength (6.6) + !shear stress (6.2)

+c!fiber–matrix bond strength/matrix shear yield strength (16.4)

+crss!critical resolved shear stress (7.5)

&m!magnetic susceptibility (20.2)

S

UBSCRIPTS c !composite

cd !discontinuous fibrous composite cl !longitudinal direction (aligned fibrous

composite)

ct !transverse direction (aligned fibrous composite)

f !final f !at fracture f !fiber

i !instantaneous m !matrix m, max ! maximum

min ! minimum 0 ! original 0 ! at equilibrium 0 ! in a vacuum

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1

A

familiar item that is fabricated from three different material types is the beverage container. Beverages are marketed in aluminum (metal) cans (top), glass (ceramic) bottles (center), and plastic (polymer) bottles (bottom). (Permission to use these photographs was granted by the Coca-Cola Company. Coca-Cola, Coca-Cola Classic, the Contour Bottle design and the Dynamic Ribbon are registered trademarks of The Coca-Cola Company and used with its express permission.)

C h a p t e r 1 Introduction

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1.1 HISTORICAL PERSPECTIVE

Materials are probably more deep-seated in our culture than most of us realize.

Transportation, housing, clothing, communication, recreation, and food production—

virtually every segment of our everyday lives is influenced to one degree or another by materials. Historically, the development and advancement of societies have been intimately tied to the members’ ability to produce and manipulate materials to fill their needs. In fact, early civilizations have been designated by the level of their materials development (Stone Age, Bronze Age, Iron Age).1

The earliest humans had access to only a very limited number of materials, those that occur naturally: stone, wood, clay, skins, and so on. With time they dis- covered techniques for producing materials that had properties superior to those of the natural ones; these new materials included pottery and various metals. Fur- thermore, it was discovered that the properties of a material could be altered by heat treatments and by the addition of other substances. At this point, materials uti- lization was totally a selection process that involved deciding from a given, rather limited set of materials the one best suited for an application by virtue of its char- acteristics. It was not until relatively recent times that scientists came to understand the relationships between the structural elements of materials and their properties.

This knowledge, acquired over approximately the past 100 years, has empowered them to fashion, to a large degree, the characteristics of materials.Thus, tens of thou- sands of different materials have evolved with rather specialized characteristics that meet the needs of our modern and complex society; these include metals, plastics, glasses, and fibers.

The development of many technologies that make our existence so comfort- able has been intimately associated with the accessibility of suitable materials.

An advancement in the understanding of a material type is often the forerun- ner to the stepwise progression of a technology. For example, automobiles would not have been possible without the availability of inexpensive steel or some other comparable substitute. In our contemporary era, sophisticated elec- tronic devices rely on components that are made from what are called semicon- ducting materials.

Lear ning Objectives

After careful study of this chapter you should be able to do the following:

1. List six different property classifications of materials that determine their applicability.

2. Cite the four components that are involved in the design, production, and utilization of materials, and briefly describe the interrelation- ships between these components.

3. Cite three criteria that are important in the ma- terials selection process.

4. (a) List the three primary classifications of solid materials, and then cite the distinctive chemical feature of each.

(b) Note the two types of advanced materials and, for each, its distinctive feature(s).

5. (a) Briefly define “smart material/system.”

(b) Briefly explain the concept of “nanotech- nology” as it applies to materials.

1The approximate dates for the beginnings of Stone, Bronze, and Iron Ages were 2.5 million

BC, 3500 BCand 1000 BC, respectively.

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1.2 Materials Science and Engineering 3

2Throughout this text we draw attention to the relationships between material properties and structural elements.

1.2 MATERIALS SCIENCE AND ENGINEERING

Sometimes it is useful to subdivide the discipline of materials science and engi- neering into materials science and materials engineering subdisciplines. Strictly speaking, “materials science” involves investigating the relationships that exist between the structures and properties of materials. In contrast, “materials engi- neering” is, on the basis of these structure–property correlations, designing or en- gineering the structure of a material to produce a predetermined set of properties.2 From a functional perspective, the role of a materials scientist is to develop or syn- thesize new materials, whereas a materials engineer is called upon to create new products or systems using existing materials, and/or to develop techniques for pro- cessing materials. Most graduates in materials programs are trained to be both materials scientists and materials engineers.

“Structure” is at this point a nebulous term that deserves some explanation. In brief, the structure of a material usually relates to the arrangement of its internal components. Subatomic structure involves electrons within the individual atoms and interactions with their nuclei. On an atomic level, structure encompasses the or- ganization of atoms or molecules relative to one another. The next larger structural realm, which contains large groups of atoms that are normally agglomerated to- gether, is termed “microscopic,” meaning that which is subject to direct observation using some type of microscope. Finally, structural elements that may be viewed with the naked eye are termed “macroscopic.”

The notion of “property” deserves elaboration. While in service use, all mate- rials are exposed to external stimuli that evoke some type of response. For exam- ple, a specimen subjected to forces will experience deformation, or a polished metal surface will reflect light. A property is a material trait in terms of the kind and mag- nitude of response to a specific imposed stimulus. Generally, definitions of proper- ties are made independent of material shape and size.

Virtually all important properties of solid materials may be grouped into six dif- ferent categories: mechanical, electrical, thermal, magnetic, optical, and deteriorative.

For each there is a characteristic type of stimulus capable of provoking different re- sponses. Mechanical properties relate deformation to an applied load or force; exam- ples include elastic modulus and strength. For electrical properties, such as electrical conductivity and dielectric constant, the stimulus is an electric field. The thermal be- havior of solids can be represented in terms of heat capacity and thermal conductiv- ity. Magnetic properties demonstrate the response of a material to the application of a magnetic field. For optical properties, the stimulus is electromagnetic or light radia- tion; index of refraction and reflectivity are representative optical properties. Finally, deteriorative characteristics relate to the chemical reactivity of materials. The chapters that follow discuss properties that fall within each of these six classifications.

In addition to structure and properties, two other important components are involved in the science and engineering of materials—namely, “processing” and

“performance.”With regard to the relationships of these four components, the struc- ture of a material will depend on how it is processed. Furthermore, a material’s per- formance will be a function of its properties. Thus, the interrelationship between processing, structure, properties, and performance is as depicted in the schematic illustration shown in Figure 1.1. Throughout this text we draw attention to the

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