2. Atomic Structure and Interatomic Bonding 18

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1 Learning Objectives Historical Perspective Materials Science and Engineering Why Study Materials Science and Engineering? Classification of Materials 5 Materials of Importance-Carbonated Beverage Containers Advanced Materials Modern Materials' Needs Processing/Structure/Properties/Performance Correlations 14 Summary 16 References 17 Question Atomic Structure and Interatomic Bonding 18 Learning Objectives Introduction 19 ATOMIC STHUCTUHE Fundamental Concepts Electrons in Atoms The Periodic Table 26 ATOMIC BONOING IN SOLlOS Bonding Forces and Energies Primary Interatomic Bonds Secondary Bonding or van der Waals Bonding 34 Materials of Importance- Water (Its Volume Expansion Upon Freezing) Molecules 38 Summary 38 Equation Summary 39 Processing/Structure/Properties/Performance Summary 40 1mportant Terms and Concepts 40 References 40 Questions and Problems 41

2 3. The Structure 01 Crystalline Solids Learning Objectives Introduction CHYSTAL STRUCTUHES 46 Fundamental Concepts 46 Unit Cells 47 Metallic Crystal Structures 47 Density Computations 51 Polymorphism and Allotropy 52 Crystal Systems 52 Materials of Importance- Tin (Its Allotropic Transformation) 53 CHYSTALLOGRAPHlC POINTS, DIRECTIONS, ANO PLANES 55 Point Coordinates 55 Crystallographic Directions 57 Crystallographic Planes 64 Linear and Planar Densities 68 Close-Packed Crystal Structures 70 CHYSTALLlNE ANO NONCHYSTALLlNE MATEHIALS 72 Single Crystals 72 Polycrystalline Materials 72 Anisotropy 73 X-Ray Diffraction: Determination of Crystal Structures 74 Noncrystalline Solids 79 Summary 80 Equation Summary 82 Process ing/s tructurel Prope rties/ Perfo rmance Summary 83 Important Terms and Concepts 83 References 83 Questions and Problems Bulk or Volume Defects 106 Atomic Vibrations 106 MICROSCOPIC EXAMINATION 107 Basic Concepts of Microscopy 107 Microscopic Techniques 108 Grain Size Determination 113 Summary 114 Equation Summary 116 Process ing/s tructurelp rope rties/ Perfo rmance Summary 117 Important Terms and Concepts 118 References 118 Questions and Problems 118 Design Problems Diflusion 122 Learning Objectives Introduction Diffusion Mechanisms Steady-State Diffusion Nonsteady-State Diffusion Factors That Influence Diffusion Diffusion in Semiconducting Materials 137 Materials of Importance-Aluminum for Integrated Circuit Interconnects Other Diffusion Paths 142 Summary 142 Equation Summary 143 Process ing/s tructurel Prop erties/ Perfo rmance Summary 144 Important Terms and Concepts 144 References 144 Questions and Problems 145 Design Problems Imperfections in Solids 90 Learning Objectives 91 Introduction 91 POINT DEFECTS 92 Vacancies and Self-Interstitials 92 Impurities in Solids 93 Specification of Composition 95 MISCELLANEOUS IMPEHFEcTloNs 99 Dislocations-Linear Defects 99 Interfacial Defects 102 Materials of Importance-Catalysts Surface Defects) 105 (and 6. Mechanical Properties 01 Metals 150 Learning Objectives 151 Introduction 151 Concepts of Stress and Strain 152 ELASTIC DEFORMATION 156 Stress-Strain Behavior 156 Anelasticity 159 Elastic Properties of Materials 160 PLASTIC DEFORMATION 162 Tensile Properties 162 True Stress and Strain 170

3 6.8 Elastic Recovery After Plastic Deformation Compressive, Shear, and Torsional Deformations Hardness 174 PnOPEHTY VAHIABILlTY ANO OESIGN/SAFETY FACI'OHS Variability of Material Properties Design/Safety Factors 182 Summary 184 Equation Summary 186 Process ingls tructure/ Pro pe rtiesl Perfo rmance Summary 187 Important Terms and Concepts 188 References 188 Questions and Problems 188 Design Problems Dislocations and Strengthening Mechanisms 197 Learning Objectives Introduction 198 OISLOCATIONS ANO PLASTIC OEFonMATloN Basic Concepts Characteristics of Dislocations Slip Systems Slip in Single Crystals Plastic Deformation of Polycrystalline Materials Deformation by Twinning MECI1ANISI\IS 01' STHENGTHENING IN METALS 211 Strengthening by Grain Size Reduction 212 Solid-Solution Strengthening 213 Strain Hardening 215 RECOVEHY, RECHYSTALLlZATION, ANO CHAIN CHOWTH 218 Recovery 219 Recrystallization 219 Grain Growth 224 Summary 225 Equation Summary 228 Process ingls tructurel Pro pe rtiesl Perfo rmance Summary 228 Important Terms and Concepts 229 References 229 Questions and Problems 229 Design Problems 233 Learning Objectives Introduction 235 FHACTUHE Fundamentals of Fracture Ductile Fracture Brittle Fracture PrincipIes of Fracture Mechanics Fracture Toughness Testing 250 FATIGUE Cyclic Stresses The S-N Curve Crack Initiation and Propagation Factors That Affect Fatigue Life Environmental Effects 264 CHEEP Generalized Creep Behavior Stress and Temperature Effects Data Extrapolation Methods Alloys for High-Temperature Use 269 Summary 270 Equation Summary 273 Important Terms and Concepts 274 References 275 Questions and Problems 275 Design Problems Phase Diagrams 281 Learning Objectives Introduction Solubility Limit Phases Microstructure Phase Equilibria One-Component (or Unary) Phase Diagrams 286 BINAHY PIIASE DIAGHAMS Binary Isomorphous Systems Interpretation of Phase Diagrams Development of Microstructure in Isomorphous Alloys Mechanical Properties of Isomorphous Alloys Binary Eutectic Systems 298 Materials of Importance-Lead-Free Solders 304

4 Development of Mierostrueture in Euteetie Alloys 305 Equilibrium Diagrams Having Intermediate Phases or Compounds 311 Euteetoid and Periteetie Reaetions 313 Congruent Phase Transformations 315 Ceramie and Temary Phase Diagrams 316 The Gibbs Phase Rule 316 THE IRON-CARBON SVSTEM The Iron-Iron Carbide (Fe-Fe3e) Phase Diagram Development of Mierostrueture in Iron-Carbon Alloys The Influenee of Other Alloying Elements 330 Summary 331 Equation Summary 333 Process ing/s tructurel Pro pe rties/ Perfo rmance Summary 334 Important Terms and Concepts 335 References 335 Questions and Problems Phase Transformations: Development of Microstructure and Alteration of Mechanical Properties 342 Learning Objeetives 343 Introduetion 343 PHASE TRANSFORMATlONS 344 Basie Coneepts 344 The Kineties of Phase Transformations 344 Metastable Versus Equilibrium States 355 MICROSTRUCTURAL AND PROPERTV CHANCES IN IRO -CARBON ALLOVS 356 Isothermal Transformation Diagrams 356 Continuous Cooling Transformation Diagrams 367 Meehanical Behavior of Iron-Carbon Alloys 370 Tempered Martensite 375 Review of Phase Transformations and Mechanieal Properties for Iron-Carbon Alloys 378 Materials of Importanee-Shape-Memory Alloys 379 Summary 381 Equation Summary 383 Proces sing/s tructurel Prope rties/ Perfo rmance Summary 384 Important Terms and Concepts 385 References 385 Questions and Problems 385 Design Problems Applications and Processing of Metal Alloys Learning Objeetives 392 Introduetion 392 TVPES OF METAL ALLOVS 393 Ferrous Alloys 393 Nonferrous Alloys 406 Materials of Importanee-Metal Alloys Used for Euro Coins 416 FABRICATIO or METALS 417 Forming Operations 417 Casting 419 Miseellaneous Teehniques 420 THEHMAL PROCESSINC OF METALS Annealing Proeesses Heat Treatment of Steels Preeipitation Hardening 436 Summary 442 Process ing/s tructurel Pro p erties/ Perfo rmance Summary 444 lmportant Terms and Concepts 444 References 447 Questions and Problems 447 Design Problems Structures and Properties of Ceramics Learning Objeetives 452 Introduetion 452 CERAMIC SmucTuRES 453 Crystal Struetures 453 Silieate Ceramies 464 Carbon 468 Materials of Importanee-Carbon Nanotubes 471 Imperfeetions in Ceramies 472 Diffusion in Ionie Materials 476 Ceramie Phase Diagrams 476

5 MECIIANICAL PROPEHTIES Brittle Fracture of Ceramics Stress-Strain Behavior Mechanisms of Plastic Deformation Miscellaneous Mechanical Considerations 489 Summary 491 Equation Summary 494 ProcessinglStruclUre/ Propertiesl Performance Summary 494 1mportant Terms and Concepts 495 References 495 Questions and Problems 495 Design Problems Applications and Processing 01 Ceramics 501 Learning Objectives Introduction Polymer Molecules 535 The Chemistry of Polymer Molecules 537 Molecular Weight 541 Molecular Shape 544 Molecular Structure 545 Molecular Configurations 547 Thermoplastic and Thermosetting Polymers 550 Copolymers 551 Polymer Crystallinity 552 Polymer Crystals 556 Defects in Polymers 558 Diffusion in Polymeric Materials 559 Summary 561 Equation Summary 563 Process ingls tructurel Propertiesl Perfo rmance Summary 564 1mportant Terms and Concepts 565 References 565 Questions and Problems Glasses Glass-Ceramics Clay Products Refractories Abrasives Cements Advanced Ceramics 509 Materials of Importance-Piezoelectric Ceramics FABHlCATlO:'o/ AND PHOCESSINC OF CEHMIICS 512 Fabrication and Processing of Glasses and Glass-Ceramics 513 Fabrication and Processing of Clay Products 518 Powder Pressing 523 Tape Casting 525 Summary 526 ProcessinglStructure/ Propertiesl Performance Summary 528 1mportant Terms and Concepts 529 References 530 Questions and Problems 530 Design Problem Polymer Structures 532 Learning Objectives Introduction Hydrocarbon Molecules Characteristics, Applications, and Processing 01Polymers 569 Learning Objectives Introduction 570 MECI-IANICAL BEI-IAVlOn 01' POLYMEnS Stress-Strain Behavior Macroscopic Deformation Viscoelastic Deformation Fracture of Polymers Miscellaneous Mechanical Characteristics MECHANISMS OF DEFOnMATlON AND Fon STHENCTI-IENINC OF POLYMEnS 581 Deformation of Semicrystalline Polymers 581 Factors That Influence the Mechanical Properties of Semicrystalline Polymers 582 Materials of Importance-Shrink-Wrap Polymer Films 587 Deformation of Elastomers 588 CnYSTALLlZATION, MELTlNC, AND CLASS TnANSITlON PHENOMENA IN POLYMEHS 590 Crystallization 590 Melting 592 The Glass Transition 592 Melting and Glass Transition Temperatures 592

6 15.14 Factors That Influence Melting and Glass Transition Temperatures 594 POLVI\1EH TVPES Plastics 596 Materials of Importance-Phenolic Billiard Balls Elastomers Fibers Miscellaneous Applications Advanced Polymeric Materials 603 POLVI\1EH SVNTHESIS ANO PHOCESSING Polymerization Polymer Additives Forming Techniques for Plastics Fabrication of Elastomers Fabrication of Fibers and Films 614 Summary 616 Equation Summary 619 Proees singls trueturel Pro pertiesl Perfo rmanee Summary 619 lmportant Terms and Coneepts 620 Referenees 620 Questions and Problems 621 Design Questions Composites 626 Learning Objectives Introduction 627 PAHTICLE-RElNFOHCEO COI\1POSITES Large-Particle Composites Dispersion-Strengthened Composites FlllEH-REINFOHCEO COI\1POSITES 634 Influence of Fiber Length 634 Influence of Fiber Orientation and Concentration 636 The Fiber Phase 645 The Matrix Phase 646 Polymer-Matrix Composites 647 Metal-Matrix Composites 653 Ceramic-Matrix Composites 655 Carbon-Carbon Composites 656 Hybrid Composites 657 Processing of Fiber-Reinforced Composites 657 STHUCTUHAL COI\1POSrTES 660 Laminar Composites 660 Sandwich Panel s 661 Materials of Importance- Nanocomposites in Tennis Balls 662 Summary 663 Equation Summary 666 Important Terms and Coneepts 667 Referenees 667 Questions and Problems 668 Design Problems Corrosion and Degradation 01 Materials 673 Learning Objectives Introduction COHHosroN 01' METALS 675 Electrochemical Considerations 675 Corrosion Rates 682 Prediction of Corrosion Rates 683 Passivity 690 Environmental Effects 692 Forms of Corrosion 692 Corrosion Environments 700 Corrosion Prevention 701 Oxidation 703 COHHOSION 01' CEHAI\1IC MATEHlALS 706 OEGHAOATIO 01' POLVMEHS 707 Swelling and Dissolution 707 Bond Rupture 709 Weathering 710 Summary 711 Equation Summary 713 Important Terms and Coneepts 714 Referenees 715 Questions and Problems 715 Design Problems Electrical Properties 719 Learning Objectives Introduction 720 ELECTHICAL CONOUCTION Ohm's Law Electrical Conductivity Electronic and Ionic Conduction Energy Band Structures in Solids Conduction in Terms of Band and Atomic Bonding Models Electron Mobility Electrical Resistivity of Metals Electrical Characteristics of Commercial Alloys 731 Materials of Importance-Aluminum Electrical Wires 731

7 SEMICONDUCTIVITY Intrinsic Semiconduction Extrinsic Semiconduction The Temperature Dependence of Carrier Concentration Factors That Affect Carrier Mobility The Hall Effect Semiconductor Devices 748 ELECTHICAL CONDUCTION IN [ONlC CEHM'IICS AND IN POLYMERS Conduction in Ionic Materials Electrical Properties of Polymers 756 DIELECTHIC BEI-IAVIOR Capacitance Field Vectors and Polarization Types of Polarization Frequency Dependence of the Dielectric Constant Dielectric Strength Dielectric Materials 765 OTIIEH ELECTRICAL CIIARACTERISTICS or MATEHIALS Ferroelectricity Piezoelectricity 767 Summary 767 Equation Summary 770 Processing/Structure/ Properties/ Performance Summary 772 Important Terms and Concepts 773 References 774 Questions and Problems 774 Design Problems Thermal Properties 781 Learning Objectives Introduction Heat Capacity Thermal Expansion 785 Materials of Importance- Invar and Other Low-Expansion AlIoys Thermal Conductivity Thermal Stresses 792 Summary 794 Equation Summary 795 Important Terms and Concepts 796 References 796 Questions and Problems 796 Design Problems Magnetic Properties Learning Objectives 801 Introduction 801 Basic Concepts 801 Diamagnetism and Paramagnetism 805 Ferromagnetism 807 Antiferromagnetism and Ferrimagnetism 809 The Infiuence of Temperature on Magnetic Behavior 813 Domains and Hysteresis 814 Magnetic Anisotropy 818 Soft Magnetic Materials 819 Materials of Importance - An Iron-Silicon Alloy That Is Used in Transformer Cores 821 Hard Magnetic Materials 822 Magnetic Storage 825 Superconductivity 828 Summary 832 Equation Summary 834 Important Terms and Concepts 835 References 835 Questions and Problems 835 Design Problems Optical Properties 840 Learning Objectives Introduction 841 BASIC CONCEPTS Electromagnetic Radiation Light Interactions with Solids Atomic and Electronic Interactions OPTICAL PHOPERTIES 01' METALS 845 OPTICAL PHOPERTIES 01' NONMETALS 846 Refraction 846 Refiection 848 Absorption 849 Transmission 852 Color 853 Opacity and Translucency in Insulators 854 ApPLlCATIONS 010 OIYI'ICAL PIIENOME'IA 855 Luminescence 855 Materials of Importance-Light-Emitting Diodes 856 Photoconductivity 858 Lasers 858

8 21.14 Optical Fibers in Communications 863 Summary 865 Equation Summary 868 1mportant Terms and Concepts 869 References 869 Questions and Problems 869 Design Problem Economic, Environmental, and Societal Issues in Materials Science and Engineering 872 Learning Objectives Introduction 873 ECONOMIC CONSIDERATIONS Component Design Materials Manufacturing Techniques 875 ENVIRONMENTAL AND SOCIETAL CONSIDERATIONS Recycling Issues in Materials Science and Engineering 878 Materials of Importance-Biodegradable and Biorenewable Polymers/ Plastics 881 Summary 884 References 884 Design Questions 885 Appendix' A The International System of Units (SI) Al Appendix' B Properties of Selected Engineering Materials A3 B.1 Density A3 B.2 Modulus of Elasticity A6 B.3 Poisson's Ratio A1ü B.4 Strength and Ductility All 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.1O Metal Alloy Compositions A29 Appendix' C Costs and Relative Costs for Selected Engineering Materials A31 Appendix' D Repeat Unit Structures for Common Polymers A36 Appendix' E elass Transition and Melting Temperatures for Common Polymeric Materials A 40 Mechanical Engineering Online Support Module Biomaterials Module elossary el Online Supporl Answers lo Selecled Problems Inde.'l: 11