Machining with Abrasives (eBook)

Preface 6
About the Editors 8
Contents 12
Contributors 14
Chapter 1: Abrasive Tools and Bonding Systems 16
1.1 Abrasive Grain Characteristics 16
1.1.1 Grain Shape 1
1.1.2 Attritious Wear Factors 23
1.1.3 Grain Fracture Toughness 26
1.2 Silicon Carbide 33
1.3 Fused Alumina 36
1.3.1 Grain Types 42
1.4 Alumina Zirconia 45
1.5 ``Ceramic´´ Sol Gel Alumina Abrasives 49
1.6 Superabrasives 53
1.6.1 Diamond 54
1.7 Vitrified Bonding Systems 58
1.7.1 Wear of Vitrified Grinding Wheels 60
1.7.1.1 Attritious Wear 61
1.7.1.2 Fracture Wear 62
1.7.1.3 Wheel Wear Mechanisms 64
1.7.2 Wheel Wear and Grinding Forces 65
1.7.3 Assessment of Grinding Forces and Wear 66
1.7.4 Effect of Workpiece Material on Wheel Wear 67
1.7.5 Effect of Abrasive and Bond Composition on Wheel Performance 69
1.7.6 Vitrified Bonding Materials 69
1.7.6.1 Effect of Particle Size of Constituent Materials 72
1.7.6.2 Effect of Mullite and Glass Content 73
1.7.6.3 Effect of Quartz Content 74
1.7.6.4 Ceramic Bonding Materials and Bond Strength 77
1.7.6.5 Effect of Interfacial Cohesion on Bond Strength and Wheel Wear 79
1.7.7 Reactions in Ceramic Bonds 81
1.7.7.1 Densification and Phase Analysis 82
Theoretical Phase Analysis: Use of Equilibrium Diagrams 82
Formation of Mullite in Kaolinite Clays 84
Effect of Heat on Feldspar and Quartz 84
Effect of Heat on Clay-Based Materials 85
Effects of Cooling 86
1.8 Conclusions 86
References 87
Chapter 2: Heat Treatment and Performance of Vitrified Grinding Wheels 93
2.1 Introduction 93
2.2 Grinding Wheel Structure Formation During Heat Treatment 94
2.2.1 Physico-Chemical Processes that Occur During Firing 97
2.2.2 Ceramic Bond Minerals that Form During Firing 99
2.3 Case Study I: Interfacial Compounds and Their Effect on Grinding Wheel Wear 106
2.3.1 Wear Mechanisms 108
2.3.1.1 Abrasive Wear 108
2.3.1.2 Fracture Wear 109
2.3.2 Microstructure of Abrasive Grains 111
2.3.2.1 High Purity Aluminum Oxide 111
2.3.2.2 Titanium-Doped Aluminum Oxide 113
2.3.2.3 Cubic Boron Nitride 113
2.3.3 Experimental Procedure 114
2.3.3.1 Measurement of Mechanical Properties 114
2.3.3.2 Manufacture of Grinding Wheels 116
2.3.3.3 Measurement of Wear 116
2.3.4 Experimental Results 116
2.3.4.1 Mechanical Properties 116
2.3.4.2 Wear of Grinding Wheels 117
2.3.5 Discussion of Interfacial Compounds on Grinding Wheel Wear 122
2.4 Case Study II: Dissolution of Quartz and Its Effect on Grinding Wheel Wear 124
2.4.1 Dissolution Models for Vitrified Grinding Wheel Bonds 127
2.4.2 Experimental Procedures 128
2.4.2.1 Raw Materials and Preparation 128
2.4.2.2 X-Ray Diffraction of Vitrified Bonding Systems 129
2.4.2.3 Grinding Wheel Performance 130
2.4.3 Experimental Results 132
2.4.3.1 Silicon Carbide Bonding Systems: Verification and Comparison of Dissolution Models for Quartz 132
2.4.3.2 Aluminum Oxide Bonding Systems: Verification and Comparison of Dissolution Models for Quartz 136
2.4.3.3 Grinding Wheel Experiments 138
2.5 Discussion 140
2.6 Conclusions 142
References 143
Chapter 3: Grinding Wheel Safety and Design 145
3.1 Introduction 145
3.2 Rotational Stresses 146
3.3 Factor of Safety 148
3.4 Segmented Grinding Wheels 149
3.5 High Speed Segmented Grinding Wheels 151
3.5.1 Grinding Wheels Capable of Being Dressed 151
3.5.2 Electroplated Grinding Wheels 152
3.6 Safety of Grinding Wheels 156
3.7 Slotted Grinding Wheels 158
3.8 Recessed Grinding Wheels 160
3.8.1 Small Cup Recessed Grinding Wheels 160
3.8.1.1 Computational Analysis 163
3.8.1.2 Experimental Methods 170
Computational Stress Analysis 170
Determination of Bursting Speed 172
Determination of Mechanical Properties of Grinding Wheels 173
3.8.1.3 Experimental Results 174
Computational Stress Analysis 174
Parallel-Sided Grinding Wheels 174
Small Cup Recessed Grinding Wheels 176
3.8.2 Large Cup Recessed Grinding Wheels 179
3.8.2.1 Computational Stress Analysis 179
3.9 Conclusions 189
References 194
Chapter 4: Dressing of Grinding Wheels 195
4.1 Introduction 195
4.2 Grinding Wheel Conditioning 196
4.2.1 Profiling 197
4.2.1.1 Stationary Dressers 197
4.2.1.2 Rotary Dressers 199
4.2.2 Sharpening 200
4.2.3 Cleaning 203
4.3 Diamond Dressing Tools 203
4.3.1 Diamond Coating 205
4.3.2 Manufacture of Diamond Dressing Tools 207
4.4 Dressing with Stationary Diamond Dressing Tools 211
4.5 Dressing with Rotary Diamond Dressing Tools 213
4.5.1 Diamond Profile Rollers 214
4.5.2 Diamond form Rollers 220
4.5.3 Diamond Cup Wheels 224
4.5.4 Crushing 225
4.5.5 Touch Dressing 226
4.5.6 Continous Dressing 228
4.6 Ultrasonic Assisted Dressing 228
4.6.1 Ultrasonic Vibration Systems 229
4.6.2 Kinematics of Ultrasonic Assisted Dressing 229
4.6.3 Ultrasonic Assisted Dressing with Stationary Dressers 231
4.6.4 Ultrasonic Assisted Dressing with Rotary Dressers 233
4.7 Laser Dressing 239
4.7.1 Principle of Laser Conditioning 240
4.7.2 Thermal Consideration of Laser Conditioning 241
4.7.3 Laser Conditioning of Conventional Grinding Wheels 242
4.7.4 Laser Conditioning of Superabrasive Grinding Wheels 244
4.8 Electro-Assisted Conditioning Methods 248
4.8.1 Electrolytic In-process Dressing 249
4.8.2 Electro-Discharge Dressing and Electrocontact Discharge Dressing 250
4.9 Conclusions 252
4.10 Nomenclature 253
References 255
Chapter 5: Surface Integrity of Materials Induced by Grinding 259
5.1 Introduction 259
5.2 Residual Stresses and Subsurface Microstructures 260
5.2.1 Grinding of Metals 260
5.2.2 Grinding of Ceramics 266
5.2.2.1 Surface Topography After Grinding 266
5.2.2.2 Subsurface Structure 268
5.2.3 Grinding of Composites 269
5.2.3.1 Influence of Fiber Orientation 271
5.2.3.2 Influence of Grinding Depth 273
5.2.3.3 Influence of Grinding Wheel Speed and Table Speed 275
5.2.4 Grinding of Monocrystalline Silicon 275
5.3 Summary 277
References 278
Chapter 6: Traditional and Non-traditional Control Techniques for Grinding Processes 282
6.1 Introduction 282
6.2 Conventional Control Techniques 283
6.2.1 Fixed-Parameter Control Technique 283
6.2.2 Adaptive Control Technique 285
6.3 Adaptive Force Control Application 288
6.4 Non-linear Adaptive Control with Self-tuning Ability 292
6.5 Adaptive Control Constraint and Adaptive Control Optimization 297
6.6 Intelligent Control Techniques 302
6.7 Hybrid Control Schemes 310
6.8 Conclusions 312
References 313
Chapter 7: Nanogrinding 316
7.1 Introduction 317
7.2 Analysis of Microstructural Deformation 317
7.3 Cutting Forces, Stress and Temperature 319
7.4 Three-Dimensional Machining Simulations 322
7.5 Experimental Nanogrinding 323
7.5.1 Analysis of Nanogrinding Grains 325
7.5.2 Fracture Dominated Wear Model 331
7.5.3 Nanogrinding Procedure 332
7.5.4 Stress Analysis 335
7.5.5 Porous Nanogrinding Tools 339
7.5.5.1 Dissolution Models for Quartz in Bonding Bridges 342
7.5.5.2 Preparation of Nanogrinding Wheel Structure 343
7.5.5.3 X-Ray Diffraction of Bonding Systems 346
7.5.5.4 Refractory Bonding Systems 347
7.5.5.5 Fusible Bonding Systems 352
7.6 Conclusions 355
References 355
Chapter 8: Polishing Using Flexible Abrasive Tools and Loose Abrasives 357
8.1 Introduction 357
8.2 Polishing with Flexible Abrasive Tools 358
8.2.1 Robotic Polishing of Aerospace Components Using Abrasive Belts 358
8.2.1.1 Work Materials and Polishing Requirements 360
8.2.1.2 Systems for Robotic Polishing 361
8.2.1.3 Part Gripper and Polishing Head 362
8.2.1.4 Robotic Polishing Processes 363
Process Parameters 363
Material Removal and Surface Finish 365
Tool Wear and Compensation 366
8.2.1.5 Process Optimization and Quality Assurance 369
8.2.2 Polishing of Fibre Optic end Faces Using Abrasive Films 371
8.2.2.1 Fibre Optic Connector and Polishing Set-Up 371
8.2.2.2 Effects of Abrasive and Polishing Protocol 372
8.2.2.3 Effect of Suspensions on Surface Quality and Optic Performance 374
8.3 Polishing with Free Abrasives 378
8.3.1 Polishing of Microbores Using Liquid Suspended Abrasive Flow 378
8.3.1.1 Experimental Apparatus and Working Principle 379
8.3.1.2 Surface Characteristics and Roughness of Polished Bores 380
8.3.2 Polishing of Free-Form Component with Free Abrasives 385
8.3.2.1 Tumbling Method and Apparatus 385
8.3.2.2 Polishing Media 387
8.3.2.3 Effects of Polishing Conditions 387
8.3.2.4 Effect of Tumbling on Buffing Cycle Time 390
8.3.2.5 Barrel Polishing 391
8.4 Concluding Remarks 392
References 394
Chapter 9: Impact Abrasive Machining 397
9.1 Introduction 397
9.2 Generation of Abrasive Jet 399
9.2.1 Pure Fluid Jet 400
9.2.2 Abrasive Jet 403
9.2.3 Design Rules 405
9.2.4 Research Directions 407
9.3 Material Removal by Impact 408
9.3.1 Ductile Erosion 410
9.3.2 Brittle Erosion 412
9.3.3 Unified Erosion Model 413
9.3.4 Material Removal by Abrasive Jet 414
9.3.5 Design Rules 417
9.4 Process Improvement 418
9.4.1 Nozzle Planar Tilting 419
9.4.2 Nozzle Lateral Tilting 420
9.4.3 Controlled Nozzle Oscillation 421
9.4.4 Multi-pass Cutting 421
9.5 Machining Operations 422
9.5.1 Milling and Its Siblings 423
9.5.2 Turning 425
9.5.3 Micro-machining 426
References 427
Index 432