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Abrasion Hardness, 2 Absolute Hardness, 72, 123 Activation Energy

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Abrasion Hardness, 2 Absolute Hardness, 72, 123 Activation Energy Index Abrasion hardness, 2 Alumina (Cont.) Absolute hardness, 72, 123 hardness (Cont.) Activation energy time effect, 140 of creep indentation creep, 234 in magnesia, 141 ion bombardment, 126 in silicon carbide, 141, 215 ISE values, 130, 259, 260-261 in tungsten carbide, 141 Knoop hardness, 86, 134, 259 of penetration, 63 pH effect, 138 of scratching, 62 water effect, 134 Adhesion of thin films, 205 Mohs number, 28 Aecheson process, 209 pendulum hardness, 28 Agglomerate toughening, 273, 275 plasticity parameter, 241 Aliovalent cations and hardening, 9 polishing agent, 45-46 AlN4 tetrahedra, 223 purity and uses, 255 Al04 tetrahedra, 223 ring crack appearance, 165 Alumina (Al20 3), 4, 255-264 scratch hardness, 29, 261 anisotropy in, 84, 256, 262 silica glass brittleness index, 188 hardness, 243 Burgers vectors, 89 modulus, 243 critical flaws in, 153, 154,259,260 toughness, 243 density, 260-261 slip systems, 89, 255 effect of pH on, 140, 262 solution hardening, 9, 262-263 effect of water on, 260 structure, 255-256 elastoplastic behavior, 49 toughness, 127, 184,257-261,278 erosion hardness, 192, 229 grain-size effect, 184, 257, 260 gamma, 262, 264 and zirconia content, 278 grain boundary Vickers hardness, 259, 260 fracture toughness, 258-259 Young's modulus, 259, 260 phases, 258 Aluminum grain-size hardness effect, 256-257 matrix for borides, 298 hardness surface hardening, 45-46 anisotropy, 81, 84, 260, 278 Vickers hardness, 46 pH effect, 262 Aluminum nitride (AlN) temperature effect, 262 hardness, 303 307 308 Index Aluminum nitride (Cont.) Applied load (Cont.) in Sicalons, 225 hardness effect, 7-9 Aluminum oxide: see Alumina and ring crack radius, 165 Amorphous layers for Rockwell hardness, 47 adherence to indenters, 129 Arrhenius behavior, 9 and barrelling, 126 Aspect ratio, 139 effect on hardness, 126, 128 of SiC, 213 from ion bombardment, 126-127 Auerbach's law, 165, 186 ISE, 128 plastic flow, 130 B6 units, bonding in, 300-301 Anisotropy, II B12 icosahedra, 228, 230, 250 in Al20 3, 262, 278 bonding in, 250-251 avoidance of, 95, 97 BaFe120I9' 285 in ,s-Al203' 280-281 Band gap, 135-136 in BN, 232 and dislocations, 250 and constraint factors, 110 and hardness, 288 of creep, 142, 293 of SiC, 214 in cubic systems, 75-80, 97 Barium titanate (BaTi03), strength after definition, 65 indentation, 185 and dislocation interaction, 71 Barrel indents, 44-126 and dislocation etch pit rosette arm BeB6 Knoop hardness, 303 length,268 Beevers-Ross sites, 280 and divergent slip systems, 116 Berkovich hardness and etching, 139 anisotropy, 94 factor, 100, 103-104 diamond, II, 39-40 in ferrites, 92 equation, 11 in graphite, 247 fracture toughness equation, 174 in hexagonal crystals, 81-86, 109-1l1 and surface energy, 198 and indent shape, 43-44, 94, 139, test, Il, 94-95 267-268 Beryl (Be3Alz,Si60 IJ, 86 in MgO, 266-268 anisotropy, 85, 88, III in orthorhombic systems, 89 Knoop hardness, 86, 88 and plastic flow, 103 slip systems, 88, III and radiation damage, 80 Beryllium oxide (BeO), Knoop hardness, and scratch hardness, 105-108 134 and slip plane polyhedra, 1l2-1l3 BezSi04 , 223 theoretical models, 97-1l6 Bhat equation, 174 in TiC, 293 Bierbaum hardness, I in zinc blende, 76, 97 Blunt punch, 12-13, 166-168 Anomalous indentation creep, 141 crack development, 166-168 Anstis equation, 174 equation for stress, 113-114 Antibonding levels flow pattern, 12 in borides, 299, 301 indenter analysis, 12, 166 in carbides, 292 and plastic zone, 111 Antifatigue, 206 Bond breaking model, 132 in glass, 241 rate equation, 132 and residual stress, 206-207 Borazon, 231 Apatite Borides, 297-301 Mohs number, 27 bonding in, 298-299 pendulum hardness, 28 hardness anisotropy, 84, 93, 108-109 Applied load Knoop hardness, 87 confidence ellipsoids, 121-123 slip systems, 108-109 effect of rate, 34-38 structures, 299 Index 309 Boddes (Cont.) {j-Al20 3 (Cont.) thermal softening coefficients, 305 critical curent density equation, 281 Boron, 4, 9, 246, 250 hardness fiber, 250 anisotropy, 81-82, 281 hardness, 231, 253 Knoop, 86 Boron carbide (B4C)' 4, 170, 226, 228 load equation, 281 bonding in, 250-251 toughness anisotropy, 281 body armor, 228 toughness equation, 281 hardness porosity relationship, 8 nomenclature, 280 equation for, 231 structure, 280 modulus, 228 zirconia composite porosity equation, 231 cracks in, 279 nonstoichiometry in, 230 toughness, 279 SiC composite hardness, 218 Vickers hardness, 279 Si3N4 composite hardness, 227 {j-graphite, 247 structure of, 230, 250 {j-parameter, 15,227 Boron nitride (BN), 4, 76, 230-234 hardness anisotropy, 76 C3 chains in B4C, 228 Knoop hardness, 83 Calcite slip systems, 76 Mohs number, 28 Boron oxide (B20 3), 4, 228, 231 pendulum hardness, 28 bonding in, 232 Carbides, 291-296 glass, hardness of, 243 bonding in, 291 polymorphism, 231 boron, 226-230 preparation, 231 cemented, 176 structure, 232 composition dependent hardness, 292 Bdnell hardness, 3, 10, 163 creep parameters, 293 damage, 26, 38, 147, 163 Vickers hardness, 92-93, 292 equation, 10 Carbon, 246-247 of SiC, 217 bonding, 247 of Si3N4, 226-227 hardness, 252 Brittleness, 4 polymorphism, 247 and conical indenter, 97 CdO in glass, 244 and cdticalload, 147 effect on hardness, 244 and erosion, 26 Cement and flow systems, 103 clinker brittleness index, 188 index, 4-5, 188 dental,46 of Al20 3, 188 hardness of, 47 of MgO, 188 energy to power, 188 of silicates, 188 strength equation, 8 Brookes Resolved Shear Stress Model, 71, Cemented carbides, 293 88, 97-111 ce02 in zirconia, 271, 275-276 development of, 110-111 hardness, 277 equation, 100 toughness, 277 BTS sensors, 287 Ceramic Bubble raft model, 129-130 covalent engineering, 209 Burgers vector, 67 magnets, 285 in Al20 3, 89 sensors, 287 analyses, 70 superconductors, 289 and dislocation interactions, 70-71 Chalcopyrites, 286 in GaAs, 113 Chemically toughened glass, 194 {j-Al20 3, 81, 255, 280-284 Chemomechanical effect on silicon, 251 bonding in, 280 Chisel edge length, 40-42 310 Index Chisel edge length (Cant.) Crack (Cant.) error in hardness, 41, 94 development summary, 168-169 Cleavage direction of magnesia, 264-265 in P-Al20 3, 281 of V20S crystals, 90 equation, 199 Coesite, 237 in polycrystalline ceramic, 199 Composite geometry factor, 181 of Al20 3-TiC, 261 growth of Al20 3-Zr02, 275 estimation, 202 hardness, 261 prevention, 202 toughness, 261 regions, 202 modulus, 261 velocity equation, 203 of a-p-SiC, 213 length body armor, 228 in glass, 195 of MgO-spinel load relationship, 161 hardness, 266 and temperature, 162 microstructure, 265 and stress corrosion, 201 of SiC-TiB2' hardness, 217 parameter of Si3N4-SiC, hardness, 227 equation, 157-158 Cone crack, 164, 166 and indenter half angle, 158 mechanism of development, 166-168 variables, 156-158 and ring crack, 166 resistance parameter, 187 and strain energy release rate, 167 stable growth, 201 Confidence ellipse, 122-123 subcritical growth, 201 Constraint factor, 11-19,99, 170 systems, 150-154, 159 for Berkovich indenter, 174 tip energies, 133 calculation for blunt punch, 12-13 velocity, 133 development of, 110-111 Cracked indents, 146 equation, 11 and dislocations, 69 of glass, 13-19 and gas release, 133 and indenter angle, 131 in MgO, 69, 267 of perspex, 13 in Na,. W03, 66 of single crystals, 13, 99 in ScsSi3, 146 and toughness, 171 in Si3N4, 219 values of, 12-13 CrB2, Vickers hardness, 93, 302 Copper slider Cr3C2, hardness, 302 and work hardening, 266 Creep Cordierite hardness, 242 activation energy, 141, 214 Corrision of carbides, 293 of cracks, 177 cortventional, 141 of dislocations, 68 of cubic BN, 233-234 of indents, 139 hardness anisotropy of MgO, 142, 266 stress effects, 201-206 Christobalite, 235-237 Corundum, 255; see also Alumina density, 237 Covariance, 122 Critical current density, 281 Crack and flaw length equation, 281 analysis, 70-71, 149-156, 159-161, 169 Critical flaw size, 153, 154, 192 critical loads, 154 in Al20 3, 154 depth in Ge, 154 and crack parameter, 156-158 in glass, 193 and fracture toughness, 187 in MgO, 153 in Ge, 163 in Si, 153-154 and load equation, 155 in SiC, 154-217 Index 311 Critical flaw size (Cont.) Daniels and Dunn equation, 99 in SiO:z, 153 Densification Critical load aids in Si3N4 , 223 for crack formation, 147, 153, 154, factor, 18 192-193 Dental cement, 46 in Al:z03, 154 Depth of penetration, 10 in Ge, 154 of aluminium, 46 in glass, 147, 154, 197 equation of, 35-36, 239 in MgO, 153, 197 equipment, 49 in Si, 153, 251 and load application, 35 in SiC, 153, 154,217 model, 49, 240 in Si3N4, 153-154 work of, 49 in SiO:z, 153, 197 Diamond, 246 in WC-Co, 153 Berkovich, 11, 94 and fracture toughness, 174 bonding and structure, 246-247 and ring cracks, 165 from beta-graphite, 247 and strength, 185 CVDfllms,247 for surface flaw generation, 196-197 hardness anisotropy, 76-77, Ill, 116 and toughened glass, 196 impurities in, 76-77 Critical resolved shear stress, 88 Knoop hardness, 83, 252 and work hardening in MgO, 266 ISE value, 130 Cross slip, 70-71 Reciprocal mean effective resolved shear Cubic BN, 231 stress curves, 102 hardness, 233 shapes for indenters, 38-42, 94, 97 from hexagonal BN, 232-233 shear modulus-hardness equation, 143 Cubic crystals slip systems, 97, 116 Knoop hardness, 82-83 structure of quartz, 236 plastic zone model, III types of, 76, 94 scratch hardness anisotropy, 106-108 Vickers hardness, 252 Vickers hardness, 90-94 Dilatational strain energy, 273 CuO:z, chains in superconductors, 290 Directional solidifcation of MgO, 256-266 Cutting tests, 1 Dislocations and surface charge, 138 around indents, 67, 113,265 and work hardening,
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