Micro-electrical Discharge Machining Processes (eBook)

Dr. Golam Kibria is an Assistant Professor at the Department of Mechanical Engineering, Aliah University, Kolkata. He graduated in Mechanical Engineering from Kalyani Government Engineering College, West Bengal. He completed his M.Tech. in Production Engineering at Jadavpur University, Kolkata in 2008, followed by his Ph.D. at the same university in 2014. After working at Sikkim Manipal University for a year he joined Aliah University, Kolkata. His research interests include non-conventional machining processes, micromachining and advanced manufacturing and forming technology. He is a life member of The Institution of Engineers (IEI), India. He has published more than 20 research articles in peer-reviewed international and national journals, and about 40 papers in conference proceedings. He has authored 5 book chapters and is also an editorial board member and reviewer for a number of respected journals. Dr. Muhammad Pervej Jahan an Assistant Professor at the Department of Mechanical and Manufacturing Engineering at Miami University. His research and teaching interests include advanced manufacturing, non-conventional manufacturing processes, and micro- and nano-machining. He received his B.S. and Ph.D. in Mechanical Engineering from Bangladesh University of Engineering and Technology (BUET) and National University of Singapore (NUS), respectively. He has published over 50 research articles in peer-reviewed journals and international conferences, and also contributed several book chapters. Dr. B. Bhattacharyya is a Professor and former Head of the Production Engineering Department, Jadavpur University. He is also the coordinator of the Center of Advanced Study Program at the University Grants Commission (UGC) and the AICTE Quality Improvement Programme at Jadavpur University. His major research areas include non-traditional machining, micromachining, and advanced manufacturing systems. He has published more than 100 research articles in national and international journals, and around 270 papers in conference proceedings. He has guided several doctoral students and also successfully completed a number of research projects. In addition to authoring several book chapters, Dr. Bhattacharyya has recently published a book titled Electrochemical Micromachining for Nanofabrication, MEMS and Nanotechnology. He is also a recipient of the Career Award of UGC, New Delhi.  

Preface 6
Acknowledgements 9
Contents 10
About the Editors 12
1 Micro-EDM Drilling 14
1.1 Introduction 14
1.2 Necessity for Micro-EDM Drilling 15
1.3 Working Principle 16
1.4 Process Parameters and Performance Criteria 18
1.5 Micro-EDM Drilling of Hard-to-Cut Materials 21
1.5.1 Stainless Steel 22
1.5.2 Ni Alloys 25
1.5.3 Ti Alloys 29
1.6 Challenges and Future Trends of Micro-EDM Drilling 31
1.7 Summary 32
References 32
2 Micro-electrical Discharge Milling Operation 35
2.1 Introduction 36
2.2 Approaches to Generate Depth in Micro-ED-Milling Operation 39
2.2.1 Layer-by-Layer Machining Approach 39
2.2.2 Bulk Machining Approach 41
2.3 Micro- Versus Macro-ED-Milling Operation: Possible Modifications 43
2.3.1 Discharge Energy Per Pulse 43
2.3.2 Tool Electrode 44
2.3.3 Inter-Electrode Gap 44
2.3.4 Resolution of the Machine Tool Axes 44
2.3.5 Short-Circuit Detection 45
2.4 Process Variables and Responses Pertaining to the µED-Milling Operation 45
2.5 Various Micro-fabrication Techniques 46
2.6 Tool Fabrication Techniques for Micro-ED-Milling Operation 48
2.7 Physical Behavior of the Micro-ED-Milling Operation 49
2.8 Micro-ED-Milling Operation with Different Variants 50
2.8.1 Insulating Ceramics 50
2.8.2 Modifications in the Dielectric Fluid 51
2.9 Allied EDM Processes for 3D Fabrication 52
2.10 Tool Wear Analysis in ED-Milling Operation 53
2.10.1 Tool Wear Compensation Techniques in Layer-by-Layer Machining 53
2.10.2 Tool Wear in Bulk Machining Approach 56
2.11 Potential Applications 59
2.12 Advantages 60
2.13 Disadvantages 60
2.14 Summary 60
References 61
3 Micro-EDM with Translational Tool Motion: The Concept of Micro-Electro-Discharge-Slotting 64
3.1 Feature Generation Using Micro-EDM with Tool Actuation: A Comparative Assessment 64
3.2 Concept of Micro-Electro-Discharge-Slotting 66
3.3 Micro-electrode Fabrication: Concept of FAST 67
3.4 Case Study: Generation of Linear Micro-slots with Conventional EDM Tool 70
3.4.1 Effect of Process Parameters on Overcut and Slot Quality 71
3.4.2 Effect of Process Parameters on Tool Wear Conditions 73
3.5 Application of Micro-ED Slotting in Micro-feature Generation 75
3.6 Summary 76
References 76
4 Micro-Wire-EDM 77
4.1 Introduction 77
4.2 Process Mechanism of Macro- and Micro-WEDM 79
4.3 Micro-wire-EDM System Components 81
4.3.1 Wire Running System 81
4.3.2 Computerized Numerical Control System (CNC System) 82
4.3.3 Power System 83
4.3.4 Dielectric Flushing System 84
4.3.5 Filtering Systems and Deionizing Subsystem 85
4.4 Micro-WEDM Parameters and Wire Materials 85
4.4.1 Electrical Parameters 85
4.4.2 Non-electrical Parameters 86
4.4.3 Wire Materials 87
4.5 Variants of Micro-wire-EDM 88
4.5.1 Cylindrical Micro-WEDM 88
4.5.2 Micro-WEDG 89
4.5.3 Rotary Disc Micro-EDG and Micro-EDM 90
4.6 Applications of Micro-wire-EDM 91
4.6.1 In Situ Microelectrode Fabrication for Micro-EDM 91
4.6.2 Microelectrode Fabrication for MEMS Application 92
4.6.3 Micro-gear Fabrication 92
4.6.4 Fabrication of PCD Planarization Tool for Polishing Silicon for Semiconductor Industries 93
4.6.5 Microstructuring of Complex 3D Parts 95
4.7 Advanced Research on Micro-wire-EDM 96
4.7.1 Applications of Micro-WEDM in Hybrid Micromachining 96
4.7.2 Modelling of the Spark Erosion and Process Mechanism 97
4.7.3 Enhancing the Performance of Micro-WEDM by Assistance of Vibration 97
4.7.4 Enhancing the Performance of Micro-WEDM of Silicon Using Conductive Coating 98
4.7.5 Development of Dry Micro-WEDM 99
4.8 Challenges in Micro-WEDM and Future Research Opportunities 99
References 100
5 Reverse Micro-EDM 103
5.1 Introduction 103
5.2 High Aspect Ratio Arrayed Features: Manufacturing Processes and Applications 104
5.3 Textured Surfaces: Manufacturing Processes and Applications 106
5.4 Basics of Reverse Micro-Electrical Discharge Machining (R-MEDM) 106
5.5 Machining of High Aspect Ratio Features Via R-MEDM 112
5.5.1 Reverse Micro-EDM of Easy-to-Erode (Brass) Material 113
5.5.2 Reverse Micro-EDM of Difficult-to-Erode (Tungsten Carbide) Material 114
5.6 Process Mechanics Comparison of R-MEDM and Micro-EDM 116
5.7 Vibration-Assisted Reverse Micro-EDM for Texturing Applications 121
5.8 Debris Modeling in Vibration-Assisted Reverse Micro-EDM 127
5.9 Summary 132
References 132
6 Micro-EDM Performance Using Different Dielectrics 135
6.1 Introduction 135
6.2 Role of Dielectric 136
6.3 Water-Based Dielectric 136
6.4 Micro-EDM with Water-Based Organic Compounds 137
6.5 Powder-Mixed Micro-EDM 138
6.6 Gas-Assisted Micro-EDM 141
6.7 Micro-EDM with Less Viscous Dielectric Oils 144
6.8 Summary 144
References 144
7 Powder-Mixed Microelectric Discharge Machining 146
7.1 Introduction 146
7.2 Working Principle 147
7.3 Pulse Generator 149
7.4 PMµEDM Process Parameters 152
7.4.1 Electrical Parameters 152
7.4.2 Non-electrical Parameters 156
7.5 Effect of Powder on IEG 157
7.6 Effect of Powder on MRR 157
7.7 Effect of Powder on Tool Wear Rate 159
7.8 Effect of Powder on Machining Time 160
7.9 Effect of Powder on Surface Roughness 161
7.10 Effect of Powder on Machined Surface 162
7.11 Research on PMµEDM 164
7.12 Summary 166
References 167
8 Vibration-Assisted Micro-EDM Process 169
8.1 Introduction 169
8.2 Challenges in Micro-EDM 170
8.3 Improvement of Machining Performances of ?-EDM with Aid of Vibration 171
8.3.1 Effects of High-Frequency Vibration 171
8.3.2 Effects of Low-Frequency Vibration 178
8.3.3 Effects of Inclined Feeding with Low-Frequency Vibration 187
8.3.4 Self-adaptive Control in Micro-EDM 189
8.4 Summary 191
References 192
9 Tool Wear Compensation in Micro-EDM 193
9.1 Introduction 194
9.1.1 ?-EDM Drilling 194
9.1.2 ?-EDM Milling 196
9.1.3 Reverse ?-EDM Method 197
9.2 Tool Wear Compensation Methodologies 199
9.2.1 Offline Tool Wear Compensation 200
9.2.2 Online Tool Wear Compensation 200
9.3 Authentication of Proposed Method 210
9.3.1 Proposed Process 210
9.3.2 Uniform Wear Method 211
9.4 Results and Discussion 212
9.5 Summary 214
References 215
10 Sequential Micro-EDM 217
10.1 Introduction 218
10.2 Advantages and Properties of Sequential Micro-EDM 219
10.3 Prerequisites of Sequential Micromachining 220
10.4 Sequential Micro-EDM and Its Applications 220
10.4.1 Sequential Micro-EDM and Micro-grinding 220
10.4.2 Sequential Micro-EDM and Micro-milling 222
10.4.3 Sequential Micro-EDM and Micro-ECM 224
10.4.4 Sequential Micro-EDM and Laser Micromachining 227
10.4.5 Sequential Micro-EDM and LIGA 230
10.4.6 Sequential Micro-EDM and Micro-turning 233
10.4.7 Sequential Micro-EDM, Micro-drilling and Electropolishing 234
10.5 Summary 235
References 236
11 Near Net Shape Machining by Micro-EDM and Micro-WEDM 238
11.1 Introduction 238
11.2 ?EDM as a Near Net Shape (NNS) Process 240
11.2.1 ?EDM for Fabricating Micro-holes and Micro-hole Array 240
11.2.2 Batch Mode Fabrication by ?EDM 247
11.2.3 3D Fabrication by Scanning/Milling ?EDM 251
11.3 ?WEDM as a Near Net Shape (NNS) Process 257
11.3.1 Wire EDM Parameters and Their Effect on Surface Roughness 259
11.3.2 Application of Wire EDM for Different Metal Composites for Near Net Shape Machining 261
11.3.3 Wire EDM for Special Geometry Design in Near Net Shape Machining 265
11.4 Summary 268
References 268
12 Micro-electrochemical Discharge Machining 272
12.1 Introduction 273
12.2 Micro-electrochemical Discharge Machining 273
12.3 Machining System and Equipments for ?-ECDM 274
12.3.1 Machining Chamber 275
12.3.2 Power Supply System 276
12.3.3 Electrolyte Feeding System 276
12.3.4 Gap Control Unit 277
12.3.5 Vision (Monitoring) System 279
12.3.6 Exhaust System 280
12.4 Electrochemical Discharge Phenomenon 280
12.4.1 Electrochemical Reactions 281
12.4.2 Coalescence of H2 Bubbles 283
12.4.3 Ionization 284
12.4.4 Electrical Discharge/Spark Formation 284
12.4.5 Cavitation 285
12.5 Mechanism of Machining 285
12.6 Configurations of ?-ECDM Process 286
12.6.1 Sinking ?-ECDM 287
12.6.2 Drilling ?-ECDM 287
12.6.3 Milling ?-ECDM 287
12.6.4 TW ?-ECDM 288
12.6.5 Grinding ?-ECDM 289
12.6.6 Turning ?-ECDM 289
12.7 Process Variables and Responses 290
12.7.1 Electrical Parameters 290
12.7.2 Tool Parameters 291
12.7.3 Electrolyte Parameters 292
12.7.4 Flushing Parameters 292
12.7.5 Process Responses 292
12.8 Process Capabilities 293
12.8.1 Merits 293
12.8.2 Demerits 293
12.8.3 Applications 294
12.9 Micro-ECDM at a Glance 295
12.10 Summary 297
References 297
13 Multi-response Optimization of Micro-EDM Processes: A State-of-the-Art Review 299
13.1 Introduction 300
13.2 Overview of µ-EDM Process 301
13.2.1 Principle of µ-EDM 301
13.2.2 A Short Review of Experimental Investigation on µ-EDM Process 302
13.3 Applications of Multi-Criteria Decision-Making (MCDM) Methods for Multi-Response Optimization of µ-EDM Processes 306
13.4 Methods for Optimization of Performance Characteristic of µ-EDM Processes 307
13.5 Summary and Future Scopes 308
References 312
Index 317