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Tung Sten Properties, Chemistry, Technology of the Element, Alloys, and Chemical Compounds

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Tung Sten Properties, Chemistry, Technology of the Element, Alloys, and Chemical Compounds Tung sten Properties, Chemistry, Technology of the Element, Alloys, and Chemical Compounds Erik Lassner and Wolf-Dieter Schubert nn Unvrt f hnl nn, Atr Kluwer Academie / Plenum Publishers New York, Boston, Dordrecht, London, Moscow Contents CHAPTER 1. The Element Tungsten: Its Properties 1.1. Analogous to Atom Related Physical Properties 1 1.1.1. Nucleus 2 1.1.2. Electron Configuration 2 1.1.3. Spectra 3 1.1.4. Thermodynamic Functions 6 1.2. Bulk Tungsten Metal Related Physical Properties 7 1.2.1. Electronic Structure and Bonding 7 1.2.2. Structural Properties 11 1.2.3. Mechanical Properties 16 1.2.4. Thermal Properties 30 1.2.5. Electromagnetic Properties 34 1.2.6. Optical Properties 36 1.2.7. Electron Emission 40 1.2.8. Acoustic Properties 42 1.3. Chemical Properties of Tungsten Metal 42 1.3.1. General Remarks 42 1.3.2. Reactions with Nonmetals 46 1.3.3. Reactions with Metals 46 1.3.4. Reactions with Compounds 50 1.3.5. Reactions with Aqueous Solutions 53 1.3.6. Miscellaneous 55 1.3.7. Reactions with Organic Compounds 56 References for Chapter 1 56 CHAPTER 2. Tungsten History: From Genesis to the 20th Century Products 2.1. The Formation of Tungsten Atoms 61 2.2 How Tungsten Atoms Came on Earth 63 2.3. Average Abundance 64 2.4. Geology: Formation of Ore Deposits 65 Ulf xv COES 2.5. Minerals 69 2.6. Ore Deposits and Reserves 70 2.7. Early Discoveries of Ores, Compounds, and of the Element 77 2.8. Technically Important Discoveries 79 2.9. Industrial Evolution 80 References for Chapter 2 83 CHAPTER 3. Important Aspects of lbngsten Chemistry 3.1. Oxidation of Tungsten Metal by Air or Oxygen 85 3.2. Reaction of Tungsten with Water 86 3.3. Reduction of Tungsten Oxides by Hydrogen 88 3.3.1. Introduction 88 3.3.2. Thermodynamic Considerations 89 3.3.3. Formation of a Volatile Tungsten Oxide Hydrate [W02(OH)2] 91 3.3.4. Kinetic Considerations 91 3.3.5. Influence of Foreign Elements 103 3.4. Reduction of Tungsten Oxides by Carbon or Carbon-Containing Compounds 107 3.5. Reduction of Tungsten Halides 110 3.5.1. Introduction 110 3.5.2. Reduction of WF6 111 3.5.3. Reduction of WC16 by Hydrogen 113 3.5.4. Reduction of WCI6 by Carbon-Containing Reagents 113 3.6. Reaction of Tungsten with Carbon or Carbon-Containing Compounds (Carburization) 114 3.6.1. Carburization of Tungsten Powder by Solid Carbon 115 3.6.2. Formation of Tungsten Carbides in Melts 118 3.6.3. Preparation of Coarse Tungsten Carbide Powder in an Auxiliary Melt 118 3.6.4. Preparation of Tungsten Carbide in Satt Melts 119 3.7. Chemistry of Aqueous Tungsten Solutions 119 3.8. Electrochemistry of Tungsten 123 3.8.1. Introduction 123 3.8.2. Cathode Reactions 125 3.8.3. Anodic Processes 125 3.8.4. Motten Salts 126 3.8.5. Practical Applications of Electrochemical Processes 126 3.8.6. Electrochromism 126 References for Chapter 3 129 CHAPTER 4. Tungsten Compounds and Their Application 4.1. Tungsten and Metals: Intermetallic Compounds and Phases 133 4.2. Tungsten and Nonmetals 133 CONTENTS xv 4.2.1. Tungsten and Boron 135 4.2.2. Tungsten and Carbon 139 4.2.3. Tungsten and Silicon 143 4.2.4. Tungsten and Nitrogen 143 4.2.5. Tungsten and Phosphorus 144 4.2.6. Tungsten and Arsenic 145 4.2.7. limgsten and Oxygen 145 4.2.8. Tungsten and Sulfirr 165 4.2.9. 'Ringsten and Selenium 167 4.2.10.Tungsten and Telluriurn 167 4.2.113ungsten and Fluorine 167 4.2.12.'Fungsten and Chlorine 169 4.2.13.Tungsten and Bromine 171 4.2.14.Tungsten and Iodine 172 4.3. Mixed Ligand and Coordination Compounds of Tungsten 173 4.3.1 Mixed Ligand Compounds 173 4.3.2. Coordination Compounds 174 4.4. Organometallic Tungsten Compounds 176 References for Chapter 4 176 CHAPTER 5. Industrial Production 5.1. Mining and Ore Beneficiation 179 5.1.1. Mining 179 5.1.2. Ore Beneficiation 179 5.2. Hydrometallurgy 184 5.2.1. Introduction including Ecological and Economical Considerations 184 5.2.2. Raw Materials and Their Treatment 187 5.2.3. Digestion—Dissolution 191 5.2.4. Purification Steps 194 5.2.5. Conversion of Sodium to Ammonium Isopolytungstate Solution . 197 5.2.6. Modem Methods in Chinese Plants 201 5.2.7. Ammonium Paratungstate Crystallization 205 5.3. The Highly Pure Intermediates 208 5.3.1. Ammonium Paratungstate (APT) 208 5.3.2. Tungsten Trioxide 212 5.3.3. Tungsten Blue Oxide (TBO) 212 5.3.4. Tungstic Acid 214 5.3.5. Ammonium Metatungstate (AMT) 214 5.4. Tungsten Metal Powder Production 215 5.4.1. General 215 5.4.2. Push-Type Fumace 221 5.4.3. Rotary Fumace 223 5.4.4. Ttuigsten Powder 225 xv CONTENTS 5.4.5. Reduction of Doped Tungsten Oxides 229 5.5. Powder Metallurgy 231 5.5.1. Compacting .231 5.5.2. Sintering 233 5.5.3. Fabrication of Tungsten 239 5.6. Alternative Processes 244 5.6.1. Electson-Beam Zone Melting 244 5.6.2. Plasma Spraying 244 5.6.3. Chemical Vapor Deposition 244 5.6.4. Physical Vapor Deposition (Sputtering) 245 5.7. Special Tungsten Forms and Qualities 245 5.7.1. Globular Tungsten Powder 245 5.7.2. Coarse Tungsten Powder 245 5.7.3. Single Crystals 246 5.7.4. Tungsten Thin Films 246 5.7.5. Porous Tungsten 246 5.7.6. High-Purity Tungsten 247 References for Chapter 5 250 CHAPTER 6. Tungsten Alloys 6.1. Substitutional Alloys (Solid-Solution Alloys) 256 6.1.1. Tungsten—Rhenium Alloys 256 6.1.2. Tungsten—Tantalum Alloys 258 6.1.3. Tungsten—Titanium Alloys 259 6.2. Dispersion-Strengthened and Precipitation-Hardening Alloys 259 6.2.1. Non-Sag Tungsten 259 6.2.2. Alloys with Oxide Dispersoids 266 6.2.3. Alloys with Carbide Dispersoids 268 6.3. Tungsten Composites 270 6.3.1. Tungsten Heavy Metal Alloys 270 6.3.2. Tungsten Copper and Twigsten Silver 276 6.3.3. Itingsten-Fiber-Reinforced Composites 278 References for Chapter 6 281 CHAPTER 7. Tungsten and Tungsten Alloy Products 7.1. Lighting Application 283 7.2. Electrical Engineering 286 7.3. Electronics 289 7.4. High-Temperature Technique 291 7.5. Welding, Cutting, Plasma Spraying, Spark Erosion, and Vapor Deposition 293 7.6. X-Rays, Radiation, Medical Engineering 297 7.7. Mechanical and Engine Engineering 298 CONTENTS :vH 7.8. Leisure Time and Sports Equipment 300 7.9. Chemical Industry and Metallurgy 301 7.10. Space Aviation 302 7.11. Military Applications 302 7.12. Aviation 304 7.13. Laser Technique 304 References for Chapter 7 305 CHAPTER 8. Tungsten in Meiting Metallurgy 8.1. Tungsten in Steel 307 8.1.1. Introduction 307 8.1.2. Master Alloys 309 8.1.3. Tungsten Alloyed Steels 312 8.2. Superalloys 317 8.3. Stellite Alloys 318 References for Chapter 8 320 CIIAPTER 9. Tungsten in Hardmetals 9.1. Introduction 321 9.2. Raw Materials 324 9.2.1. Tungsten Carbide Powder 324 9.2.2. Other Carbide Powders 343 9.2.3. Binder Metals 344 9.2.4. Other Materials 344 9.3. Hardmetal Production 345 9.3.1. Preparation of Powder Grades 345 9.3.2. Powder Consolidation 348 9.3.3. Sintering 348 9.3.4. Postsinter Treatments 351 9.4. Hardmetal Qualities and Applications 353 References for Chapter 9 362 CHAPTER 10. Tungsten in Cataiysis 10.1. Metallic Tungsten 365 10.1.1. Survey 365 10.1.2. Hydrodesulfurization and Hydrodenitrogenation 365 10.2. Oxides 366 10.2.1. Survey 366 10.2.2. DENOX SCR Catalysts 366 10.3. Halides 368 10.4. Carbon Compounds 368 Miii COES 0.4.. Srv 68 0.4.2. rprtn f Crbd Ctlt 6 0.4.. WC 6 0.4.4. W2C 0 0.4.. ntn Crbd Ctlt n hr—rph Snth 0.. Orntntn Cpnd: Ctlt n OM nd AME 0.6. ntt 4 0.. Chlnd 4 frn fr Chptr 0 4 CHAPTER 11. Tungsten Scrap Recycling .. Intrdtn nd Gnrl Cndrtn .2. ntn ln Mthd 80 .2.. drtllr 80 .2.2. Mltn Mtllr 8 .2.. rt ln 8 .2.4. Sdrt ln 84 frn fr Chptr 8 CHAPTER 12. Ecology 2.. Intrdtn 8 2.2. Mnn nd Or rn 88 2.. Chl Cnvrn 2 2.4. dr Mtllr 4 2.. Envrnntl Cndrtn bt th Sbtttn f h Spd Stl b rdtl 4 frn fr Chptr 2 4 CHAPTER 13. Economy .. Intrdtn .2. Wrld Mn rdtn 6 .. r f ntn .4. Sppl nd nd 40 .. Cnptn nd U 40 .6. h "Intrntnl ntn Indtr Atn" (MA 406 fr fr Chptr 40 CHAPTER 14. Tungsten and Living Organisms 4.. Intrdtn 40 4.2. ntn n tr (ntn Enz 40 CONTENTS :ix 4.. ntn nd Anl 42 4... t 42 4..2. M 42 4... Gn 4 4..4. bbt 4 4.4. ntn nd n 4 4.4.. Iprtnt t 4 4.4.2. rdtl 4 4.4.. nfl Infln 44 frn fr Chptr 4 46 Indx 4.
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