The structure of materialsPDF电子书下载

Chapter 1 The Structure of Materials：Overview 1

1.1 Descriptors and Averaging 3

1.2 Preliminary Concepts 5

1.2.1 Symmetry 5

1.2.2 Bonding 11

Types of Bonds 12

Structural Descriptors of Bonded Materials 15

Molecular Geometry 17

Polyatomic Covalently Bonded Molecules：Electron-Domain Theory 18

Shape Diversity in Large Molecules and Macromolecules 20

1.2.3 Coordination Number 22

1.2.4 Packing Fraction 22

1.2.5 Order and Disorder 23

1.3 Structure of Materials Roadmap 25

References 28

Additional Reading 28

Exercises 28

Chapter 2 Noncrystalline State 31

2.1 Generic Descriptors 35

2.1.1 Short-Range Order 35

2.1.2 The Glass Transition and Free Volume 37

2.1.3 Pair-Distribution Function 39

2.1.4 Symmetry of Glass Structure and Physical Properties 43

2.2 Hard-Sphere Models 43

2.2.1 Bernal’s Random Close-Packed Sphere Model 44

2.2.1 Voronoi Polyhedra 48

2.3 Random-Walk Models 51

2.3.1 Brownian Motion and Diffusion 51

2.3.2 Polymeric Glasses and Melts 56

Thermoplastics 57

Polymer Conformations 60

Polymer Composition，Architecture and Tacticity 61

2.4 Network Models 63

2.4.1 Oxide Glasses 65

2.4.2 Thermosetting Polymers 69

2.4.3 Chalcogenide Glasses 72

Xerography：An Application of Noncrystalline Semiconductors 73

2.5 Fractal Models 74

2.5.1 Dilation Symmetry and Fractal Dimension 74

2.5.2 Ordered Fractals 76

2.5.3 Irregular Fractals 77

2.5.4 Diffusion-Limited Aggregation 77

2.5.5 Fractals and Fracture 80

References 80

Additional Reading 81

Exercises 81

Chapter 3 Crystalline State 89

3.1 The Crystallography of Two Dimensions 91

3.1.1 Translational Symmetry 91

Lattices 91

Primitive Cells，Multiple Cells，and Unit Cells 93

Notation for Rational Points and Rational Lines 95

3.1.2 Reflectional and Glide Symmetry 97

3.1.3 Rotational Symmetry 99

Proper Rotation Axes 99

Limitation of Rotational Symmetries in Crystals due to Translational Periodicity 101

3.1.4 Plane Point Groups 103

Derivation of Plane Point Groups by Combining Reflections and Rotations 103

General and Special Positions 106

International and Schoenflies Symbols 107

3.1.5 The Five Distinct Plane Lattices 108

Plane Lattice Nets Arising from Crystallographic Rotation Axes and Translations 109

Lattice Nets Arising from Mirror Lines and Translations 112

3.1.6 Plane Groups 114

Addition of Reflectional Symmetry to Plane Lattices 116

The Seventeen Distinct Crystallographic Plane Groups 117

3.1.7 The International Tables for Crystallography：Plane Groups 119

Symbols and Notation 120

Description of Two-Dimensional Patterns by Crystallographic Data 122

Generation of Two-Dimensional Patterns from Crystallographic Data 124

Summary of Information Concerning Plane Groups 126

3.2 The Crystallography of Three Dimensions 126

3.2.1 Symmetry Operations Unique to Three Dimensions 126

Inversion 126

Rotoinversion 127

Rotoreflection 129

Screw Axes 130

3.2.2 Techniques for Three-Dimensional Spatial Relationships 135

Rational Intercept Plane：Miller Indices 135

Direction Common to Two Planes，Zone Axes，Weiss Zone Law 138

Spherical Trigonometry 140

Stereographic Projection 143

3.2.3 Axial Combinations of Rotational Symmetries 146

Simultaneous Rotational Symmetries 146

Permissible Combinations of Rotational Axes in Three-Dimensional Crystals 147

3.2.4 The Thirty-Two Crystallographic Point Groups 151

Decomposition of Improper Rotation Axes 152

Derivation of Point Groups by Adding Extenders to Permissible Axial Combinations 153

Schoenflies Notation for the Crystallographic Point Groups 158

Laue Groups 159

3.2.5 Space Lattices 159

Principles of Derivation by Stacking of Plane Lattices 162

The Fourteen Bravais Lattices and Six Crystal Systems 166

Conventional Unit Cells for the Crystal Lattices 168

3.2.6 Space Groups 170

Glide Planes 170

Derivation Method for Space Groups 172

3.2.7 The International Tables for Crystallography：Space Groups 173

3.3 Symmetry Constraints on Material Properties 179

3.3.1 Transformation of a Vector 181

3.3.2 Transformation of a Tensor 181

3.3.3 Tensor Properties of Crystals 182

3.3.4 Symmetry Constraints 185

3.4 Hard-Sphere Packing and Crystal Structure 189

3.4.1 Close-Packed Structures 191

3.4.2 Interstitial Sites in Close-Packed Structures 194

3.4.3 Close Packing in Ionic Compounds 195

3.5 Quasicrystals 196

3.5.1 Aperiodic Tiling Patterns 197

3.5.2 Icosahedral Structures in Crystals 201

References 201

Additional Reading 202

Exercises 202

Chapter 4 Liquid-Crystalline State 213

4.1 Structural Classes of Liquid Crystals 218

4.1.1 Nematic Phase 220

4.1.2 Twisted Nematic Phase 221

4.1.3 Smectic Phase 223

4.1.4 Columnar Phase 226

4.2 Descriptors for Liquid Crystals 227

4.2.1 Pair-Distribution Function 227

4.2.2 Orientational Order Parameter 228

4.2.3 Translational Order Parameter 231

4.3 Mesophase Texture and Identification of Liquid-Crystalline Phases 233

4.4 Applications of Liquid Crystals 233

4.4.1 Surfactants 233

4.4.2 Liquid-Crystalline Fibers 235

4.4.3 Liquid-Crystal Displays 237

4.4.4 Next-Generation Flexible Liquid-Crystal Displays 239

4.5 Plastic Crystals 242

References 242

Additional Reading 243

Exercises 243

Chapter 5 Imperfections in Ordered Media 249

5.1 Point Imperfections 251

5.1.1 Vacancies 251

5.1.2 Interstitials 255

5.1.3 Point Imperfections in Molecular Crystals 257

5.1.4 Mobility of Point Imperfections 260

5.1.5 Solid Solutions 260

5.1.6 Point Imperfections in Ionic Crystals 263

Kroger-Vink Notation 264

Schottky and Frenkel Imperfections 265

Imperfections Associated with Impurities 267

5.2 Line Imperfections 271

5.2.1 Dislocations 273

Evidence for Dislocations 276

Characterization of Dislocations：Tangent Vector and Burgers Vector 280

Dislocation Motion by Slip and Climb 283

Dislocation Loops 287

Slip Systems 290

Resolved Shear Stress on a Dislocation 294

Elastic Energy of Dislocations 298

Strengthening Mechanisms in Crystals 298

Generation of Dislocations 304

Dislocations in Columnar Crystals 307

5.2.2 Disclinations 307

5.3 Surface Imperfections 313

5.3.1 Surface Tension and Surface Free Energy 313

5.3.2 Geometry of Grain Structures 316

5.3.3 Equilibrium at Interfacial Junctions 318

5.3.4 Structure of Crystalline Interfaces 321

Stacking Faults 322

Antiphase Boundaries 324

Grain Boundaries 327

Interphase Grain Boundaries 332

Grain Boundaries in Block Copolymers 334

Magnetic Domain Walls 335

Walls in Liquid Crystals 339

5.4 Imperfections and Symmetry Breaking 340

References 340

Additional Reading 341

Exercises 341

Chapter 6 Microstructure 349

6.1 Structural Hierarchies 350

6.1.1 Structural Hierarchy in a Metal Forging 352

6.1.2 Structural Hierarchy in a Semicrystalline Polymer 354

6.2 Microstructures Arising from Special Processing 357

6.2.1 Deformation Microstructures 358

Deformation Processing and Crystallographic Texture 358

Microstructures of Deformed Polycrystalline Materials 359

Characterization of Textures：X-Ray Pole Figures 361

6.2.2 Transformation Microstructures 364

Solidification Microstructures 364

Solid-Solid Transformation Microstructures 370

Composite Microstructures 374

6.3 Microstructural Case Studies 379

6.3.1 Nickel-Base Superalloys 380

6.3.2 Thermoset/Carbon-Fiber Composite Laminates 385

6.4 Where Do We Go From Here？ 389

References 391

Additional Reading 391

Exercises 393

Index 397