Selected Topics in High Temperature Chemistry (eBook)

Defect Chemistry of Solids

A.G. Andersen, o. Johannesen (Herausgeber)

eBook Download: PDF

2017 | 1. Auflage
412 Seiten
Elsevier Science (Verlag)
978-1-4832-9101-7 (ISBN)

Infos

The properties of materials at high temperature play a vital role in their processing and practical use. The real properties of materials at elevated temperatures are very often governed by defects in their structure. Lattice defects may consist of point defects like vacancies, interstitial atoms or substituted atoms. These classes are discussed in general and specifically for oxides, nitrides, carbides and sulfides. Defect aggregates, shear structures and adaptive structures are also described. Special attention is paid to hydrogen defects which seem to play an important role in several materials.
Defects in solids lead to transport properties such as diffusion and conductivity. These themes are thoroughly treated in this book, with examples from various materials being provided. Special attention is paid to the transport properties of grain boundaries. In high temperature corrosion and other types of oxidation, the diffusion of atoms through the reaction products is often the rate limiting step of the reaction. This book takes the reader from the theoretical treatment of defects to applications in high temperature corrosion. Reactions between metals and pure oxygen lead to the formation of oxides on the surface, and the reaction rates may often be related to the diffusion coefficients of the oxide. However, in practical use alloys are subjected to other severe gaseous atmospheres which may often lead to accelerated attack on the material. The severest condition, namely where a salt deposit is combined with oxidizing gases, is called hot corrosion. This and other types of corrosion are also covered. Finally, a chapter is devoted to the prevention of corrosive attack on materials by the addition of rare earth metals.
The book has been published in honour of Professor Per Kofstad on the occasion of his 60th birthday. Professor Kofstad has for many years been active in the field of high temperature chemistry in all its aspects, from basic and theoretical work to its application in high temperature corrosion of metals and alloys. The various chapters have been contributed by his friends and colleagues, all of whom are international experts in the field.

Inhalt

Front Cover 1
Selected Topics in High Temperature Chemistry: Defect Chemistry of Solids 4
Copyright Page 5
Table of Content 14
Dedication 6
Professor Per Kofstad 8
Preface 12
List of Contributors 20
CHAPTER 1. DEFECTS IN INORGANIC COMPOUNDS 22
1. Introduction 22
2. Defects in Crystalline Compounds 22
3. The Stoichiometric Composition 32
4. Nonstoichiometry 37
5. The Law of Mass Action 39
6. Defect Association 43
7. Summary 47
References 48
CHAPTER 2. DEFECTS AND DIFFUSION IN METAL OXIDES 50
1. Introduction 50
2. Theoretical Basis 50
3. Experimental Techniques 55
4. Self-Diffusion in Binary Oxides 57
5. Dopants, Impurities and Ternary Oxides 64
6. Other Types of Diffusion 71
References 72
CHAPTER 3.SIMILARITIES AND DIFFERENCES IN DEFECT DEPENDENT PROPERTIES OF TRANSITION METAL SULPHIDES AND OXIDES 76
1. Introduction 76
2. General Remarks 76
3. Defect Structure and Nonstoichiometry 81
4. Transport Properties 97
5. Conclusions 116
References 117
CHAPTER 4.HYDROGEN DEFECTS IN INORGANIC SOLIDS 122
1· Introduction 122
2. Hydrogen and Hydrogen Ions 124
3. Protons in Oxides 125
4. Other Hydrogen Defects in Oxides 139
5. Hydrogen Defects in other Classes of Compounds 141
6. Proton Transport 142
7. Methods for Studying Hydrogen and Hydrogen Transport 146
8. Practical Uses and other Aspects of Protons in Ceramics 156
9. Summary 159
References 160
CHAPTER 5. ENHANCED IONIC CONDUCTIVITY IN INORGANIC SOLIDS 164
1. Introduction 164
2. Solid Oxide Electrolytes 166
3. Defect Structure 168
4. Electrical Conductivity 169
5. Point Defect Associations 173
6. Highly Defective Fluorite Oxides 179
7. Grain Boundary Effects 187
8. Homovalent Substitution in Mixed Alkali Halides 195
References 203
CHAPTER 6. LATTICE AND GRAIN-BOUNDARY DIFFUSION PROCESSES INVOLVED IN THE HIGH-TEMPERATURE OXIDATION AND SULFIDATION OF METALS AND ALLOYS 206
1. Introduction 206
2. Pure Metals 207
3. Alloys 220
References 245
CHAPTER 7. EFFECTS OF RARE EARTH ELEMENTS ON THE HIGH TEMPERATURE OXIDATION OF HEAT-RESISTING ALLOYS 248
1. Introduction 248
2. Oxidation Behavior of Heat-Resisting Alloys 249
3. Improvements of Oxidation Resistance by Rare Earth Effect 252
4. Rare Earth in Chromia - Forming Alloys 259
5. Rare Earth Effect in Alumina-Forming Alloys 274
6. Conclusions 281
References 281
CHAPTER 8. MECHANISMS OF OXIDATION AND SULFIDATION OF HIGH TEMPERATURE ALLOYS IN H2-H2O-H2S MIXTURES 284
1. Introduction 284
2. Mechanisms of Corrosion in H2-H2O-H2S Atmospheres 287
3. Protection against Corrosion in Coal Gasification Atmospheres 296
4. Conclusions 305
References 308
CHAPTER 9. HOT CORROSION OF MATERIALS 312
1. Introduction 312
2. Early Kinetic/Mechanistic Studies 313
3. Thermodynamics and Salt Chemistry 316
4. Phase Stability and Oxide Solubilities 319
5. Mechanisms for Type I Hot Corrosion 327
6· Complexing Solutions/Strong Acids 339
7. Hot Corrosion of Oxides 344
8. Type II (Low Temperature) Hot Corrosion 345
References 348
CHAPTER 10. FORMATION OF THE COMPOUNDS Fe4N AND Fe3C VIA GAS-METAL REACTIONS AND DERIVED PROPERTIES OF THESE COMPOUNDS 352
1. Dedication 352
2. Introduction 352
3. Experimental 353
4. Results and Discussion 354
5. Summary and Conclusions 369
References 372
CHAPTER 11. POINT DEFECT AND TRANSPORT PROPERTIES IN CARBIDES AND NITRIDES 374
1. Introduction 374
2. Brief Characterization of Carbides and Nitrides 376
3. Order-Disorder in Non-Stoichiometric NaCl-Type Carbides and Nitrides 381
4. Thermal Disorder and Calculations of Defect Energies 382
5. Feasibility of and Difficulties with Point Defect and Diffusion Measurements in Carbides and Nitrides 385
6. Diffusion in Carbides and Nitrides 387
7. Supporting Measurements on Point Defects: Quenching, Radiation Damage, Channeling 400
8. Summary 403
References 404
Subject Index 406

Produkt-Details

• Erscheint lt. Verlag: 31.1.2017
• Sprache: englisch
• Themenwelt: Naturwissenschaften ► Chemie ► Physikalische Chemie
• Themenwelt: Naturwissenschaften ► Chemie ► Technische Chemie
• Themenwelt: Naturwissenschaften ► Physik / Astronomie ► Thermodynamik
• Themenwelt: Technik ► Maschinenbau
• Themenwelt: Technik ► Umwelttechnik / Biotechnologie
• ISBN-10: 1-4832-9101-4 / 1483291014
• ISBN-13: 978-1-4832-9101-7 / 9781483291017