Chemistry and Physics of Mechanical Hardness

<p>Preface xi</p>
<p>1 Introduction 1</p>
<p>1.1 Why Hardness Matters (A Short History) 1</p>
<p>1.2 Purpose of This Book 5</p>
<p>1.3 The Nature of Hardness 7</p>
<p>2 Indentation 11</p>
<p>2.1 Introduction 11</p>
<p>2.2 The Chin–Gilman Parameter 14</p>
<p>2.3 What Does Indentation Hardness Measure? 14</p>
<p>2.4 Indentation Size Effect 20</p>
<p>2.5 Indentation Size (From Macro to Nano) 22</p>
<p>2.6 Indentation vs. Scratch Hardness 23</p>
<p>2.7 Blunt or Soft Indenters 24</p>
<p>2.8 Anisotropy 24</p>
<p>2.9 Indenter and Specimen Surfaces 25</p>
<p>3 Chemical Bonding 27</p>
<p>3.1 Forms of Bonding 27</p>
<p>3.2 Atoms 28</p>
<p>3.3 State Symmetries 29</p>
<p>3.4 Molecular Bonding (Hydrogen) 31</p>
<p>3.5 Covalent Bonds 36</p>
<p>3.6 Bonding in Solids 41</p>
<p>3.7 Electrodynamic Bonding 45</p>
<p>3.8 Polarizability 47</p>
<p>4 Plastic Deformation 51</p>
<p>4.1 Introduction 51</p>
<p>4.2 Dislocation Movement 52</p>
<p>4.3 Importance of Symmetry 55</p>
<p>4.4 Local Inelastic Shearing of Atoms 56</p>
<p>4.5 Dislocation Multiplication 57</p>
<p>4.6 Individual Dislocation Velocities (Microscopic Distances) 59</p>
<p>4.7 Viscous Drag 60</p>
<p>4.8 Deformation–Softening and Elastic Relaxation 62</p>
<p>4.9 Macroscopic Plastic Deformation 63</p>
<p>5 Covalent Semiconductors 67</p>
<p>5.1 Introduction 67</p>
<p>5.2 Octahedral Shear Stiffness 69</p>
<p>5.3 Chemical Bonds and Dislocation Mobility 71</p>
<p>5.4 Behavior of Kinks 75</p>
<p>5.5 Effect of Polarity 77</p>
<p>5.6 Photoplasticity 79</p>
<p>5.7 Surface Environments 80</p>
<p>5.8 Effect of Temperature 80</p>
<p>5.9 Doping Effects 80</p>
<p>6 Simple Metals and Alloys 83</p>
<p>6.1 Intrinsic Behavior 83</p>
<p>6.2 Extrinsic Sources of Plastic Resistance 85</p>
<p>7 Transition Metals 99</p>
<p>7.1 Introduction 99</p>
<p>7.2 Rare Earth Metals 101</p>
<p>8 Intermetallic Compounds 103</p>
<p>8.1 Introduction 103</p>
<p>8.2 Crystal Structures 104</p>
<p>8.3 Calculated Hardness of NiAl 112</p>
<p>8.4 Superconducting Intermetallic Compounds 113</p>
<p>8.5 Transition Metal Compounds 115</p>
<p>9 Ionic Crystals 119</p>
<p>9.1 Alkali Halides 119</p>
<p>9.2 Glide in the NaCl Structure 120</p>
<p>9.3 Alkali Halide Alloys 123</p>
<p>9.4 Glide in CsCl Structure 124</p>
<p>9.5 Effect of Imputities 124</p>
<p>9.6 Alkaline Earth Fluorides 126</p>
<p>9.7 Alkaline Earth Sulfi des 128</p>
<p>9.8 Photomechanical Effects 128</p>
<p>9.9 Effects of Applied Electric Fields 129</p>
<p>9.10 Magneto–Plasticity 129</p>
<p>10 Metal–Metalloids (Hard Metals) 131</p>
<p>10.1 Introduction 131</p>
<p>10.2 Carbides 132</p>
<p>10.3 Tungsten Carbide 134</p>
<p>10.4 Borides 136</p>
<p>10.5 Titanium Diboride 137</p>
<p>10.6 Rare Metal Diborides 138</p>
<p>10.7 Hexaborides 138</p>
<p>10.8 Boron Carbide (Carbon Quasi–Hexaboride) 140</p>
<p>10.9 Nitrides 141</p>
<p>11 Oxides 143</p>
<p>11.1 Introduction 143</p>
<p>11.2 Silicates 143</p>
<p>11.3 Cubic Oxides 147</p>
<p>11.4 Hexagonal (Rhombohedral) Oxides 152</p>
<p>11.5 Comparison of Transition Metal Oxides with "Hard Metals" 155</p>
<p>12 Molecular Crystals 157</p>
<p>12.1 Introduction 157</p>
<p>12.2 Anthracene 158</p>
<p>12.3 Sucrose 159</p>
<p>12.4 Amino Acids 159</p>
<p>12.5 Protein Crystals 160</p>
<p>12.6 Energetic Crystals (Explosives) 161</p>
<p>12.7 Commentary 161</p>
<p>13 Polymers 163</p>
<p>13.1 Introduction 163</p>
<p>13.2 Thermosetting Resins (Phenolic and Epoxide) 164</p>
<p>13.3 Thermoplastic Polymers 165</p>
<p>13.4 Mechanisms of Inelastic Plasticity 166</p>
<p>13.5 "Natural" Polymers (Plants) 166</p>
<p>13.6 "Natural" Polymers (Animals) 168</p>
<p>14 Glasses 171</p>
<p>14.1 Introduction 171</p>
<p>14.2 Inorganic Glasses 172</p>
<p>14.3 Metallic Glasses 176</p>
<p>14.3.1 Hardness Shear Modulus Relationship 177</p>
<p>14.3.2 Stable Compositions 180</p>
<p>15 Hot Hardness 183</p>
<p>15.1 Introduction 183</p>
<p>15.2 Nickel Aluminide versus Oxides 184</p>
<p>15.3 Other Hard Compounds 184</p>
<p>15.4 Metals 185</p>
<p>15.5 Intermetallic Compounds 187</p>
<p>16 Chemical Hardness 189</p>
<p>16.1 Introduction 189</p>
<p>16.2 Defi nition of Chemical Hardness 190</p>
<p>16.3 Physical (Mechanical) Hardness 192</p>
<p>16.4 Hardness and Electronic Stability 193</p>
<p>16.5 Chemical and Elastic Hardness (Stiffness) 194</p>
<p>16.6 Band Gap Density and Polarizability 194</p>
<p>16.7 Compression Induced Structure Changes 195</p>
<p>16.8 Summary 196</p>
<p>17 "Superhard" Materials 197</p>
<p>17.1 Introduction 197</p>
<p>17.2 Principles for High Hardness 197</p>
<p>17.3 Friction at High Loads 198</p>
<p>17.4 Superhard Materials 199</p>
<p>References 200</p>
<p>Index 203</p>