Machining Difficult-to-Cut Materials (eBook)

Preface 6
Contents 8
1 Introduction 14
Abstract 14
1.1 Historical Background 14
1.1.1 Stone Age 14
1.1.2 Bronze Age 15
1.1.3 Iron Age 16
1.2 Modern Engineering Materials 17
1.2.1 Steels 18
1.2.2 Titanium and Its Alloys 18
1.2.3 Superalloys 19
1.2.4 Metal Matrix Composites (MMCs) 19
1.2.5 Ceramics 19
1.3 Superior Characteristics, Major Challenges 20
Reference 20
2 Hardened Steels 21
Abstract 21
2.1 Introduction 21
2.1.1 Heat Treatment 22
2.1.2 Cryogenic Treatment 23
2.1.3 Case Hardening 24
2.1.3.1 Carburizing 24
2.1.3.2 Gas Nitriding 25
2.1.3.3 Induction Hardening 25
2.1.3.4 Flame Hardening 25
2.2 Historical Background and Evolution of Hardened Steels 26
2.3 Metallurgy of Hardened Steels 28
2.4 Characteristics of Hardened Steels 31
2.4.1 High Indentation Hardness 31
2.4.2 Low Ductility (Brittleness) 31
2.4.3 High Hardness/E-modulus Ratio 31
2.4.4 Corrosion Sensitivity 32
2.5 Industrial Applications of Hardened Steels 32
2.5.1 Applications of Case-Hardened Steels 33
2.5.2 Applications of Induction Hardened Steels 33
2.5.3 Applications of Carburized Steels 34
2.6 Challenges in the Machining of Hardened Steels 35
2.7 Hard Turning 37
2.7.1 Hard Turning as an Alternative for Grinding 38
2.7.2 Special Features of Hard Turning 39
2.7.3 Rigidity Imposed Limitations in Hard Turning 41
2.7.4 Surface Quality and Integrity 41
2.7.4.1 Formation of White Layer 41
2.7.4.2 Residual Stresses 44
2.7.4.3 Material Side Flow 45
2.8 Mechanics of Chip Formation During Hard Turning 46
2.9 Influential Factors on Chip Formation During Hard Turning 50
2.9.1 Nose Radius 50
2.9.2 Edge Preparation and Tool Condition 50
2.9.3 Feed 51
2.10 Dynamics of Chip Formation 54
2.11 Cutting Forces During Hard Turning 55
2.12 Appropriate Tool Materials for Hard Turning 56
2.12.1 CBN and PCBN Tools 57
2.12.2 Ceramic Tools 60
2.12.3 Cermet (Solid Titanium Carbide) Tools 61
2.13 Surface Finish in Hard Turning 62
2.14 Environmentally Friendly Hard Turning 63
2.15 Hard Milling 63
2.16 Concluding Remarks 64
References 64
3 Titanium and Titanium Alloys 67
Abstract 67
3.1 Introduction 67
3.2 Historical Background and Evolution of Titanium 69
3.3 Metallurgy of Titanium 71
3.3.1 Alpha (?) Alloys 73
3.3.2 Near-Alpha (?) Alloys 73
3.3.3 Alpha-Beta (??+??) Alloys 74
3.3.4 Metastable Beta (?) Alloys 74
3.3.5 Beta (?) Alloys 75
3.3.6 Titanium Aluminides 75
3.4 Characteristics of Titanium and Its Alloys 76
3.5 Industrial Applications of Titanium and Its Alloys 80
3.5.1 Aerospace Applications 80
3.5.2 Chemical and Petrochemical Applications 83
3.5.3 Automotive Applications 84
3.6 Challenges in the Machining of Titanium and Its Alloys 86
3.6.1 Poor Thermal Conductivity 87
3.6.2 Chemical Reactivity 89
3.6.3 Low Modulus of Elasticity 89
3.6.4 Hardening Effect 90
3.7 Mechanics of Chip Formation 90
3.7.1 Chip Segmentation Under Adiabatic Shear 92
3.8 Appropriate Tool Materials and Modes of Tool Wear 97
3.8.1 HSS Tools 98
3.8.2 Carbide Tools 99
3.8.3 Ceramic Tools 101
3.8.4 CBN and PCBN Tools 101
3.8.5 Diamond Tools 102
3.9 Application of Coolant in the Machining of Titanium 103
3.9.1 Utilization of Nano-cutting Fluids 104
3.10 Concluding Remarks 105
References 106
4 Superalloys 109
Abstract 109
4.1 Introduction 109
4.2 Historical Background and Evolution of Superalloys 111
4.3 Metallurgy of Superalloys 115
4.3.1 Phases of Superalloys 117
4.3.1.1 Gamma (?) Phase 117
4.3.1.2 Gamma Prime (??) Phase 117
4.3.1.3 Gamma Double Prime (??) Phase 118
4.3.1.4 Carbides 118
4.3.2 Strengthening Mechanisms 118
4.4 Detailed Classification of Superalloys 120
4.4.1 Iron-Based Superalloys 121
4.4.2 Nickel-Based Superalloys 123
4.4.3 Cobalt-Based Superalloys 125
4.5 Characteristics of Superalloys 127
4.5.1 Tensile and Yield Properties 127
4.5.2 Creep Resistance 127
4.5.3 Fatigue Resistance 127
4.5.4 Corrosion Resistance 127
4.6 Industrial Applications of Superalloys 128
4.6.1 Application of Superalloys in Gas Turbines and Jet Engines 128
4.7 Challenges in the Machining of Superalloys 131
4.7.1 High Hot Hardness and Strength 133
4.7.2 High Dynamic Shear Strength 133
4.7.3 Low Thermal Conductivity 134
4.7.4 Formation of Built-up Edge 135
4.7.5 Austenitic Matrix and Work Hardening During Machining 135
4.7.6 Abrasiveness 136
4.8 Mechanics of Chip Formation in Machining of Superalloys 136
4.9 Tool Materials for Conventional Machining of Superalloys 139
4.9.1 Appropriate Cutting Tools for Turning of Superalloys 141
4.9.2 Appropriate Cutting Tools for Milling of Superalloys 143
4.9.3 Modes of Tool Wear When Machining Superalloys 143
4.10 Application of Coolant in the Machining of Superalloys 145
4.11 Concluding Remarks 146
References 147
5 Metal Matrix Composites 150
Abstract 150
5.1 Introduction 150
5.2 Historical Background and Evolution of MMCs 152
5.2.1 First Generation 153
5.2.2 Second Generation 153
5.2.3 Third Generation 154
5.2.4 Fourth Generation 155
5.3 Characteristics of Metal Matrix Composites 156
5.3.1 High-Strength and Improved Transverse Properties 156
5.3.2 High Stiffness and Toughness 157
5.3.3 High Operational Temperature 157
5.3.4 Low Sensitivity to Surface Defects 157
5.3.5 Good Thermal and Electrical Conductivity 157
5.4 Classifications of Metal Matrix Composites 158
5.4.1 Classification of MMCs Based on Matrix Materials 158
5.4.1.1 Aluminum Alloys 158
5.4.1.2 Titanium Alloys 158
5.4.1.3 Magnesium Alloys 159
5.4.1.4 Cobalt 159
5.4.1.5 Copper 159
5.4.1.6 Silver 159
5.4.1.7 Nickel 159
5.4.1.8 Niobium 160
5.4.1.9 Intermetallic Compounds 160
5.4.2 Classification of MMCs Based on the Type of Reinforcement 160
5.4.2.1 Particle-Reinforced MMCs 161
5.4.2.2 Discontinuous Fiber-Reinforced MMCs 161
5.4.2.3 Continuous Fiber and Sheet-Reinforced MMCs 162
5.5 Industrial Applications of Metal Matrix Composites 163
5.5.1 Aerospace Applications 164
5.5.2 Automotive and Transportation Applications 165
5.6 Challenges in the Machining of Metal Matrix Composites 165
5.6.1 Machining of Particulate-Reinforced MMCs 166
5.6.1.1 Chip Formation in the Machining of Particulate-Reinforced MMCs 170
5.6.1.2 Cutting Forces in the Machining of Particulate-Reinforced MMCs 172
5.6.2 Machining of Fiber-Reinforced MMCs 176
5.6.2.1 Chip Formation When {{/varvec /uptheta}} = {/bf 0^/circ} 177
5.6.2.2 Chip Formation When {{/bf 0}}^/circ /le{/varvec /theta}/le {{/bf 90}}^/circ 178
5.6.2.3 Chip Formation When {/bf 90^/circ} /le{/varvec /theta}/le {/bf 180^/circ} 179
5.7 Appropriate Tools Materials and Modes of Tool Wear 179
5.7.1 Analytical Modeling of Wear Progression 183
5.8 Concluding Remarks 185
References 186
6 Ceramics 189
Abstract 189
6.1 Introduction 189
6.2 Historical Background and Evolution of Ceramics 190
6.3 Material Structure of Ceramics 193
6.3.1 Polycrystalline Ceramics Made by Sintering 194
6.3.2 Glass 194
6.3.3 Glass Ceramics 194
6.3.4 Single Crystals of Ceramic Compositions 194
6.3.5 Chemical Synthesis or Bonding 195
6.3.6 Natural Ceramics 195
6.4 Characteristics of Ceramic Materials 195
6.4.1 Brittleness 195
6.4.2 Poor Electrical and Thermal Conductivity 195
6.4.3 Compressive Strength 196
6.4.4 Chemical Insensitivity 196
6.5 Industrial Applications of Ceramics 196
6.5.1 Structural Applications 196
6.5.2 Electronic Applications 197
6.5.3 Bio-Applications 197
6.5.4 Coating Applications 198
6.5.5 Composites Applications 198
6.6 Challenges in the Machining of Ceramics 199
6.7 Mechanism of Chip Formation 200
6.8 Turning of Ceramic Materials 201
6.9 Grinding of Ceramic Materials 203
6.10 Ultrasonic Machining of Ceramic Materials 204
6.11 Abrasive Water Jet Machining of Ceramic Materials 206
6.12 Electrical Discharge Machining of Ceramic Materials 209
6.13 Laser Machining of Ceramic Materials 211
6.14 Application of Coolant in the Machining of Ceramics 212
6.15 Concluding Remarks 212
References 213
7 Environmentally Conscious Machining 215
Abstract 215
7.1 Introduction 216
7.2 Traditional Cutting Fluids 218
7.2.1 Non-Water-Miscible Cutting Fluids 219
7.2.2 Water-Miscible and Water-Based Cutting Fluids 220
7.2.3 Gaseous, Air, and Air–Oil Mists (Aerosols) Cutting Fluids 223
7.2.4 Cryogenic Cutting Fluids 223
7.3 Advanced Nano-Cutting Fluids 223
7.3.1 Characterization and Performance of Nano-Cutting Fluids 225
7.3.2 Challenges in the Application of Nano-Cutting Fluids 225
7.4 Delivery Methods of Cutting Fluids 226
7.4.1 Low-Pressure Flood Cooling 226
7.4.2 High-Pressure Flood Cooling 227
7.4.3 High-Pressure Through-Tool Cooling 228
7.4.4 Mist Cooling 228
7.5 Cutting Fluids and Their Consequent Health Hazards 228
7.5.1 Toxicity 229
7.5.2 Dermatitis 229
7.5.3 Respiratory Disorders 230
7.5.4 Microbial Disorders 230
7.5.5 Cancer 231
7.6 Environmental Considerations in Machining 231
7.6.1 Machining with Minimum Quantity Lubrication (MQL) 233
7.6.2 Dry Machining 234
7.7 Special Cutting Tools 236
7.7.1 Self-propelled Rotary Tools 237
7.7.1.1 Self-Cooling Feature of Rotary Tools 240
7.8 Machining Titanium and Superalloys Using Rotary Tools 241
7.9 Machining Hardened Steels Using Rotary Tools 243
7.10 Concluding Remarks 244
References 245
Index 249