net This page www.net intentionally left blank www.net Copyright © 2004, New Age International (P) Ltd., Publishers Published by New Age International (P) Ltd., Publishers All rights reserved. No part of this ebook may be reproduced in any form, by photostat, microfilm, xerography, or any other means, or incorporated into any information retrieval system, electronic or mechanical, without the written permission of the publisher. All inquiries should be emailed to rights@newagepublishers.com ISBN (13) : 978-81-224-2656-4 PUBLISHING FOR ONE WORLD NEW AGE INTERNATIONAL (P) LIMITED, PUBLISHERS 4835/24, Ansari Road, Daryaganj, New Delhi - 110002 Visit us at www.net Preface www.net Material Science has become a very important subject as an interdisciplinary course in almost all univer- sities. Keeping this in view we have developed the subject matter for B., Diploma in engineering, M.) courses as per their latest syllabii. The book is also useful for UPSC, GATE, NET, SLET and other entrance examinations. A reasonably wide coverage in sufficient depth has been attempted, giving the importance to the basic principles, essential theory and experimental details necessary for understanding the nature, properties and applications of materials. All efforts have been made to provide topics which are of great use to the readers, e. semiconductors, superconductors, polymers, composites, nanostructured materials, etc. Latest develop- ments, e. quantum dots, spinotrics, MOSFET, Microelectronic circuits, MEMS, nanotechnology, etc. are also covered. To make the text more useful, good number of worked out problems, review questions, problems, short- question answers, typical objective questions, suggested readings are provided with each chapter. We are thankful to M/s New Age International (P) Limited Publishers, for their untiring efforts in bringing out the book with excellent printing and nice get up within the shortest possible time period. Suggestions for the improvement of the book are most welcome. Kakani February 2004 Amit Kakani www.net This page www.net intentionally left blank www.net Contents www. Classification and Selection of Materials 1 1. Classification of Engineering Materials 5 4. Organic, Inorganic and Biological Materials 7 5. (a) Current Trends and Advances in Materials 10 7. (d) Nanostructured Materials and Nanotechnology 12 7. (g) Fermionic Condensate Matter 13 8. Level of Material Structure Examination and Observation 13 9. Selection of Materials 14 Suggested Readings 17 Review Questions 17 Problems 18 Short Question-Answers 18 Objective Questions 19 2. Atomic Structure, and Electronic Configuration 20 1. Atomic Weight and Mass Number 22 7. Avogadro’s Number (N) 24 www.net viii Contents 11. Vector Atom Model 43 14. Pauli Exclusion Principle and Electronic Configuration of Atoms 47 16. Wave Mechanical Picture of the Atom 54 17. Periodic Table 56 Suggested Readings 59 Review Questions 59 Problems 60 Short Questions 61 Objective Questions 61 Short Question-Answers 63 www. Crystal Geometry, Structure and Defects 64 1. Lattice Points and Space Lattice 66 5. Crystal Structure for Metallic Elements 75 11. Density of Crystal 79 13. Directions, Lattice Planes and Miller Indices 80 14. (a) Angle Between Two Planes or Directions 84 15. Representation of Crystal Planes in a Cubic Unit Cell 84 16. Sketching the Plane from the given Miller Indices 86 17. Common Planes in a Simple Cubic Structure 86 18. Co-ordination Number 87 19. Defects or Imperfections in Crystals 95 20. Line Defects or Dislocations 98 22. Surface and Grain Boundary Defects 101 23. Frank-Read Source 106 27. Theory of Dislocations: Salient Features 107 28. Determination of Crystal Structure by X-Ray Diffraction 110 29. Bragg’s X-ray Spectrometer 112 30. Methods of Determining Crystal Structure 118 32. Electron and Neutron Diffraction 121 www.net Contents ix 33. Crystal Growth 122 Suggested Readings 123 Review Questions 123 Problems 124 Objective Questions 125 Short Questions Answers 127 4. Bonds in Solids 129 1. Types of Bonds 129 3. Forces Between Atoms: Mechanism of Bond Formation and Bond Energy 131 4. Covalent Bond 140 www. Comparison of Ionic, Covalent and Metallic Bonds 144 8. Properties of Solid Materials 148 11. Periodic Table and Chemical Bonding: Electronegativity 150 Suggested Readings 151 Review Questions 151 Problems 152 Objective Questions 153 Short Question Answers 154 5. Electron Theory of Metals 155 1. Drude-Lorentz Theory 156 4. Sommerfield Free-Electron Theory 156 5. Fermi-Dirac Distribution Function (Electron Energies in a Metal) 159 6. Band Theory of Solids 160 7. Distinction between Conductors, Insulators and Semiconductors 163 9. Electrical Resistance of Materials 164 10. Equation of Motion of an Electron 166 12. Resistivity and Conductivity 167 13. Current Density in Metal 167 14. Mean Free Path 171 16. Origin of the Thermoelectric Effect 174 18. Magnitude and Direction of Thermo E. Uses of Thermocouples 175 Suggested Readings 175 Review Questions 176 Problems 176 Objective Questions 176 Short Question Answers 177 www. Experimental Arrangement to Study the Photo Electric Effect 179 3. Failure of Classical Theory 182 4. Einstein’s Photoelectric Equation 183 5. Millikan’s Verification of Einstein’s Equation 184 6. Uses of photoelectric Cells 191 Suggested Readings 194 Review Questions 194 Problems 194 Objective Questions 195 Short Question-Answers 196 www. Diffusion in Solids 197 1. Types of Diffusion 197 3. Diffusion Coefficient: Fick’s Laws of Diffusion 199 5. Dependence of Diffusion Coefficient on Temperature 202 6. Factors Affecting Diffusion Coefficient (D) 202 7. Experimental Determination of D using a Diffusion Couple 203 10. Diffusion with Constant Concentration (Case Hardening) 204 11. The Kirkendall Effect 204 12. Diffusion in Oxides and Ionic Crystals 205 13. Activation Energy of Diffusion 205 15. Applications of Diffusion 206 Suggested Readings 210 Review Questions 210 Problems 211 Objective Questions 211 Short Question-Answers 212 8. Mechanical Properties of Materials and Mechanical Tests 213 1. Atomic Model of Elastic Behaviour 226 4. Modulus (Y ) as a Parameter of Design 227 5. Fundamental Mechanical Properties 228 Stress-Rupture Test 243 6. Factors affecting Mechanical Properties 244 7. Non-Destructive Testing (NDT) 258 9. Fracture 260 Suggested Readings 272 Review Questions 272 Problems 274 www.net Contents xi Objective Questions 274 Short Question-Answers 276 9. Alloy Systems, Phase Diagrams and Phase Transformations 279 1. The Families of Engineering Alloys 283 5. Hume-Rothery’s Rules 285 6. Intermediate Phases or Intermediate Compounds (or Intermediate Solid Solutions) 286 7. The Phase Rule or Gibb’s Phase Rule or Condensed Phase Rule 287 9. Cooling Curves (Time-Temperature Curves) 288 www. Construction of a Phase Diagram or Constitutional Diagram 289 11. The Lever Rule 290 12. Equilibrium Diagrams for Binary Alloys Forming Eutectic 292 13. Ceramic and Ternary phase Diagrams 294 14. Applications of Phase Diagrams 295 15. The Kinetics of Solid State Reactions 296 18. Applications of Phase Transformations 300 20. Micro-constituents of Fe-C System 302 21. Allotropic forms of Iron 304 21. Iron-carbon System 305 22. Iron-carbon equilibrium or Phase Diagram 305 23. Modified Iron-carbon Phase Diagram 306 24. Formation and Decomposition of Austenite 309 25. Types and Properties of Carbon-Steels 311 26. Isothermal Transformations-TTT Diagram 312 27. Transformation of Austenite upon Continuous Cooling 314 28. Transformation of Austenite to Martensite 315 29. Metals for Nuclear Energy 316 Suggested Readings 318 Review Questions 318 Problems 319 Short Question Answers 319 Objective Questions 320 10. Heat-Treatment Processes 322 3. Principal Equipment for Heat Treatment 336 7. Major Defects in Metals or Alloys due to Faulty Heat Treatment 338 8. Surface Finish After Heat Treatment 339 9. Measurement of High Temperatures and Pyrometers 340 www.net xii Contents Suggested Readings 344 Review Questions 344 Problems 345 Short Question-Answers 346 Objective Questions 346 11. Deformation of Materials 348 1. Deformation by Twinning 355 5. Comparison between Slip and Twinning 356 6. Plastic Deformation of Polycrystalline Materials 357 www. Work Hardening or Strain Hardening 357 8. Adiabatic and Isothermal Straining 360 12. Yield Point Phenomenon and Related Effects 361 13. Atomic Diffusion–An Elastic After Effect 363 14. Recovery, Recrystallization and Grain Growth 365 16. Hot-Working 368 Suggested Readings 371 Review Questions 371 Problems 372 Objective Questions 373 Short Question Answers 373 12. Oxidation and Corrosion 375 1. Corrosion-resistant Materials 375 3. High Temperature Oxidation or Dry Corrosion 382 7. Specific Forms of Corrosion 383 10. Corrosion Prevention and Control 388 11. Corrosion Monitoring and Management 394 Suggested Readings 396 Review Questions 396 Problems 397 Short Question-Answers 397 Objective Questions 398 13. Thermal and Optical Properties of Materials 400 Section A: Thermal Properties 400 1.net Contents xiii 2.) 416 Section B: Optical Properties 418 1. Interactions of Light with Solids 418 3. Atomic and Electronic Interactions 418 www. Optical Properties of Metals 419 5. Optical Properties of Non metals 420 6. Applications of Optical Phenomena 424 Suggested Readings 426 Review Questions 427 Problems 428 Objective Questions 428 Short Question-Answers 430 14. Electrical and Magnetic Properties of Materials 431 1. Electronic and Ionic Conduction 435 5. Band Structure in Solids 435 6. Conduction in Terms of Band and Atomic Bonding Models 438 7. Electrical Resistivity of Metals 440 8. Electrical Characteristics of Alloys Used for Commercial Purposes 442 9. Mechanisms of Strengthening in Metals 442 10. Magnetism 456 Suggested Readings 480 Review Questions 480 Problems 482 Objective Questions 483 Short Question Answers 484 15. Semiconductors in Computers 518 7. Microelectromechanical Systems (MEMS) 519 www.net xiv Contents 9. Spintronics 520 Suggested Readings 522 Review Questions 523 Problems 523 Objective Questions 524 Short Question Answers 525 16. Superconductivity and Superconducting Materials 526 1. HTSC Cuprate Materials Characteristics 532 4. Characteristic Properties of Superconductors 535 www. Properties of HTSC Oxides 541 7. Thermodynamics of a Superconductor 542 8. Theory of Superconductivity 544 9. Applications of Superconductivity 548 Suggested Readings 551 Review Questions 551 Short Questions 552 Problems 552 Objective Questions 553 Short Question Answers 553 17. Organic Materials: Polymers and Elastomers 555 1. Basic Concepts of Polymer Science 559 5. Thermoplastic and Thermosetting Polymers 568 7. Defects in Polymers 570 10. Mechanical Properties of Polymers 570 11. Mechanisms of Deformation 572 12. Crystallization, Melting and Glass Transition Phenomena in Polymers 572 13. Miscellaneous Applications of Polymers 578 15. Advanced Polymeric Materials 579 16. Manufacturing Processes Involving Polymers 582 18. Behaviour of Polymers 585 20. Fabrication of Fibres and Films 586 21. Wood 587 Suggested Readings 588 Review Questions 589 www.net Contents xv Problems 590 Objective Questions 590 Short Questions Answers 591 18. Particle-Reinforced Composites 596 4. Fibre-Reinforces Composites 598 5. Fabrication 609 Suggested Readings 611 Review Questions 611 Problems 611 www.net Objective Questions 612 Short Question Answers 612 19. Production Methods for CNTs 621 3. Key Issues in Nanomanufacturing 624 4. Mechanical and Electronic Properties of Carbon Nanotubes 624 5. Nanostructures in Motion 624 6. Nanomaterial Advantage 624 Suggested Readings 626 Review Questions 626 Appendix 1: Units, Conversion Factors, Physical Constants 627 Units 627 Appendix 2: Conversion Factors 630 Appendix 3: Physical Constants 632 Appendix 4: Prefix Names, Symbols and Multiplication Factors 633 Subject Index 634 www.net This page www.net intentionally left blank www.net 1 Classification and Selection of Materials www. INTRODUCTION Materials science and engineering plays a vital role in this modern age of science and technology. Various kinds of materials are used in industry, housing, agriculture, transportation, etc. to meet the plant and individual requirements. The rapid developments in the field of quantum theory of solids have opened vast opportunities for better understanding and utilization of various materials. The spectacular success in the field of space is primarily due to the rapid advances in high-temperature and high-strength materials. The selection of a specific material for a particular use is a very complex process. However, one can simplify the choice if the details about (i) operating parameters, (ii) manufacturing processes, (iii) functional requirements and (iv) cost considerations are known. Factors affecting the selection of materials are sum- marized in Table 1.
