Front Cover 1
Anti-Abrasive Nanocoatings 4
Copyright Page 5
Contents 6
List of figures 12
List of tables 24
About the editor 26
About the contributors 28
Preface 42
Part One 46
1 Wear, friction and prevention of tribo-surfaces by coatings/nanocoatings 48
1.1 Introduction 48
1.2 Friction of materials 49
1.2.1 Friction of metals, alloys and composites 53
1.2.1.1 Effect of operating parameters 54
1.3 Wear in metals, alloys and composites 55
1.3.1 Effect of operating parameters 55
1.4 Materials and their selection for wear and friction applications 57
1.4.1 Cast irons 57
1.4.2 Steels 57
1.4.3 Other bearing alloys 58
1.4.4 Metal-matrix composites and nanocomposites 58
1.4.5 Selection 60
1.5 Coatings/nanocoatings and surface treatments 60
1.5.1 Thermal spray coatings 61
1.5.2 Electroplated coatings 61
1.5.3 Ion implantation 63
1.5.4 PVD and CVD 63
1.5.5 Carburizing 63
1.5.6 Nitriding and nitro-carburizing 63
1.5.7 Laser surface processing 63
1.6 Conclusion 64
Acknowledgements 64
References 64
2 An investigation into the tribological property of coatings on micro- and nanoscale 68
2.1 Drivers of studying the origin of tribology behavior 68
2.2 Contact at nanometer scale 72
2.2.1 Methodology 75
2.2.2 Results and discussion 76
2.2.3 Conclusion 81
2.3 Atomic friction with zero separation 82
2.3.1 Methodology 83
2.3.2 Results and discussion 84
2.3.3 Conclusion 91
2.4 Scratching wear at atomic scale 92
2.4.1 Methodology 92
2.4.2 Results and discussion 94
2.4.3 Concluding remarks 98
2.5 Conclusion 99
References 99
3 Stress on anti-abrasive performance of sol-gel derived nanocoatings 102
3.1 Classical curvature stress for thin films on plate substrates 103
3.2 Thermal stress of thin films 106
3.3 Why do drying films crack? 106
3.4 Cracks by stress come from constraint of shrinkage by the substrate 108
3.5 Rapid sol-gel fabrication to confront tensile trailing cracks 111
3.6 Anti-abrasive SiO2 film in application: self-assembling covalently bonded nanocoating 113
3.7 Abrasive test 114
3.8 Anti-abrasive performance of sol-gel nanocoatings 117
3.8.1 The process of obtaining sol-gel nanocoatings 117
3.8.2 Cross-sectional morphology 118
3.8.3 Surface morphology 119
3.8.4 Mechanical performance 120
3.9 Conclusion 121
Acknowledgments 122
References 122
4 Self-cleaning glass 126
4.1 Introduction 126
4.2 History of glass 128
4.3 Self-cleaning glass 129
4.4 Hydrophilic coating 130
4.5 Anti-reflective coating 131
4.6 Porous materials 131
4.7 Photocatalytic activity of TiO2 133
4.8 Hydrophobic coatings 134
4.9 Fabrication of self-cleaning glass 135
4.9.1 Top-down approach 136
4.9.1.1 Lithography 136
4.9.2 Bottom-up approach 136
4.9.2.1 Chemical vapour deposition 136
4.9.2.2 Plasma arc evaporation 137
4.9.2.3 Sol-gel process 138
4.9.2.3.1 Spin coating 139
4.9.2.3.2 Dip coating 139
4.9.2.3.3 Spray coating 140
4.9.2.4 Self-assembly 141
4.9.2.5 SiO2-TiO2 coating 141
4.9.2.6 Visible light 143
4.10 Application of self-cleaning glasses 144
4.10.1 Advantages 144
4.10.2 Disadvantages 144
Acknowledgements 144
References 144
5 Sol-gel nanocomposite hard coatings 150
5.1 Introduction 150
5.2 Sol-gel nanocomposite hard coatings 151
5.3 Mechanical property studies of sol-gel hard coatings on various substrates 155
5.3.1 Adhesion 155
5.3.1.1 Indentation technique 155
5.3.1.2 Scratch testing 156
5.3.1.3 Cross-hatch cut and scotch tape test 159
5.3.1.4 Pull-off adhesion test 161
5.3.2 Pencil hardness 164
5.3.3 Nanoindentation hardness 166
5.3.4 Abrasion resistance 171
5.3.4.1 Crockmeter method 171
5.3.4.2 Taber test method 172
5.4 Possible applications of hard coatings 174
5.5 Summary 177
Acknowledgments 177
References 177
6 Process considerations for nanostructured coatings 182
6.1 Overview 182
6.2 Anti-reflection coatings 185
6.3 Fluidized bed method 188
6.4 Electroplating 189
6.5 Nanografting 190
6.6 Plasma spray coating 190
6.7 Nanostructuring in thin films 191
6.8 Electrochemical deposition 192
6.9 Anti-corrosion coating 194
6.10 Infrared transparent electromagnetic shielding 194
6.11 Underlying science – self-assembly 195
6.12 Conclusions 196
References 197
Part Two 200
7 Nanostructured electroless nickel-boron coatings for wear resistance 202
7.1 Introduction 202
7.2 Synthesis of electroless nickel-boron coatings 202
7.2.1 General principle of electroless deposition 203
7.2.2 Thermodynamic and kinetic conditions for electroless deposition of metals 203
7.2.3 Possible reducing agents for electroless nickel deposition 206
7.2.4 Components of an electroless nickel-boron bath and their role 207
7.2.5 Reactions in nickel-boron deposition baths, control parameters 208
7.2.6 Importance of substrate preparation 212
7.2.7 Preparation methods for the most common alloys 214
7.3 Morphology and structure of electroless nickel-boron coatings 216
7.3.1 General aspect and plating rate 216
7.3.2 Morphology, microstructure and chemistry 216
7.3.3 Structure 220
7.3.3.1 Structure of as-deposited electroless nickel-boron 220
7.3.3.2 Structure of heat treated electroless nickel-boron 222
7.4 Mechanical and wear properties of nanocrystalline electroless nickel-boron coatings 223
7.4.1 Hardness 224
7.4.2 Roughness 228
7.4.3 Adhesion and scratch testing behaviour 230
7.4.4 Wear resistance 233
7.4.4.1 Friction coefficient 234
7.4.4.2 Abrasive wear resistance 234
7.4.4.3 Sliding wear resistance 236
7.5 Corrosion resistance 236
7.6 Conclusion 237
References 240
8 Wear resistance of nanocomposite coatings 246
8.1 Introduction 246
8.1.1 The importance of coatings in the wood industry 246
8.1.1.1 Water-based coatings 247
8.1.1.2 Reinforcing fillers 247
8.1.2 The special case of nanosize fillers 248
8.1.2.1 Cellulose nanocrystals: a potential reinforcing filler for coatings 250
8.2 Materials and methods 251
8.2.1 Cellulose nanocrystals 251
8.2.2 CNC particle size measurement by light scattering 253
8.2.3 Coating formulations preparation: dispersion method 253
8.2.4 Preparation of the formulations 253
8.2.5 Wood samples preparation 254
8.2.6 Atomic force microscopy 255
8.2.7 Scanning electron microscopy and elemental analysis 256
8.2.8 Abrasion resistance 256
8.2.9 Scratch resistance 256
8.3 Results and discussion 256
8.3.1 CNC samples characterization 256
8.3.2 Polymerized coating formulations characterization 257
8.3.3 Influence of the sonication on the CNC dispersion 261
8.3.4 Abrasion resistance 262
8.3.5 Scratch resistance 263
8.3.6 Multilayer coatings 263
8.4 Conclusions 265
Acknowledgments 265
References 266
9 Machining medical grade titanium alloys using nonabrasive nanolayered cutting tools 270
9.1 Metallurgical Aspects 270
9.1.1 Introduction 270
9.1.2 Basic aspects of titanium metallurgy 270
9.1.3 Mechanical behavior 275
9.2 Machining of titanium alloys 278
9.3 Machining with coated cutting tools: a case study 279
9.3.1 Material analysis 280
9.3.2 Coating analysis 280
9.3.3 Experimental parameters and procedure 281
9.3.4 Experimental data 281
9.3.4.1 Surface roughness 281
9.3.4.2 Flank wear of tool inserts 284
9.3.4.3 Wear images of tool inserts 284
9.3.4.4 Economic analysis 286
9.4 Conclusions 291
Acknowledgments 291
References 291
10 Functional nanostructured coatings via layer-by-layer self-assembly 294
10.1 Introduction 294
10.2 LbL process 295
10.2.1 Spin-assisted LbL nanoassembly 297
10.2.2 Spray-assisted LbL assembly 298
10.2.3 Substrates, polyelectrolytes, nanoparticles 298
10.2.4 Parameters 299
10.2.4.1 Ionic strength and pH 299
10.2.4.2 Media, concentration, immersion time 301
10.3 LbL-deposited nanostructured coatings with different functions 303
10.3.1 Hard, anti-abrasive, and anti-scratching coatings via LbL 303
10.3.2 Self-healing, anti-corrosive coatings 310
10.3.3 Flame-retardant nanocoatings 311
10.3.4 Barrier coatings 315
10.3.5 Antimicrobial coatings 319
10.4 Conclusions 322
Acknowledgment 322
References 322
11 Theoretical study on an influence of fabrication parameters on the quality of smart nanomaterials 328
11.1 Introduction 328
11.2 Literature survey on VO2 329
11.3 Synthesis techniques description 333
11.3.1 Comparative discussion 333
11.4 Conclusion 336
References 336
12 Formation of dense nanostructured coatings by microarc oxidation method 338
12.1 Introduction 338
12.2 Phenomena of MAO-coating formation 338
12.3 Voltage–current characteristics 340
12.4 Discussion about growth mechanism of MAO coating 342
12.5 Model of fractal growth of the dense wear-resistant layer 346
12.5.1 Algorithm for generating densely structured MAO coating 349
12.5.2 Algorithm 350
12.5.2.1 Initialization 350
12.5.2.2 Running the program 350
12.6 Macro- and microstructure of MAO coatings 354
12.7 Wear-resistant properties 360
12.8 Conclusion 372
References 372
13 Current trends in molecular functional monolayers 376
13.1 Introduction 376
13.2 Steps for self-assembly 377
13.3 Mechanism 380
13.4 Characterization of SAMs 381
13.5 Use of SAMs for various applications 382
13.5.1 Antistiction coatings and MEMS devices 382
13.5.2 Anti-reflection coatings 384
13.5.3 Injection molding industry 385
13.5.4 Organic monolayers and transistors 385
13.5.5 Monolayers on silicon with controlled levels of functionality 385
13.5.6 Modification of electronic properties of carbon nanotube 386
13.6 Self-assembled monolayers on gold substrates 386
13.7 Si-C monolayer formation and C-C bonding 387
13.8 Supramolecular assembly on surface–host-guest interactions and other non-covalent bonding 389
13.9 Self-assembled monolayers on other surfaces such as titania nanotubes 389
13.10 Chemical and electrical biosensors 390
13.11 Quality improvement 390
13.12 Conclusions 391
References 392
14 Surface engineered nanostructures on metallic biomedical materials for anti-abrasion 394
14.1 Introduction 394
14.2 Surface technologies on metallic biomedical materials for anti-abrasion 398
14.2.1 Chemical/electrochemical action 401
14.2.2 Sandblasting 406
14.2.3 Shot peening and laser shock peening 409
14.2.4 Physical vapor deposition 411
14.2.5 Chemical vapor deposition 414
14.2.6 Plasma spraying 416
14.3 Future prospects 420
References 421
15 Theoretical modeling of friction and wear processes at atomic level 430
15.1 Introduction 430
15.2 MD method 432
15.3 Quantum chemistry methods 434
15.3.1 Basic ideas of DFT 434
15.3.2 Cluster model 436
15.4 Basic types of problems 436
15.4.1 Calculation of coefficient of friction 436
15.4.2 Interaction of grease molecules with a metal surface 438
15.4.3 Solid coverings 439
15.4.4 Tribochemical reactions 443
15.4.5 Influence of grain boundary segregation on wear resistance of polycrystalline materials 444
15.5 Lubrication and one-electron transfers 445
15.6 Conclusion 447
References 448
16 Mechanical characterization of thin films by depth-sensing indentation 452
16.1 Introduction 452
16.2 Hardness 453
16.3 Young’s modulus 459
16.4 Conclusion 467
Acknowledgements 467
References 468
Part Three 472
17 Advanced bulk and thin film materials for harsh environment MEMS applications 474
17.1 Introduction 474
17.2 Piezoelectric substrates 476
17.3 Non-piezoelectric substrates 481
17.4 Thin piezoelectric films 482
17.4.1 High coupling efficiency 483
17.4.2 TCD 484
17.4.3 High operation frequency 486
17.4.4 High temperature measurements 487
17.5 Metal electrodes 489
17.6 Conclusion 492
References 492
18 Plasma-assisted techniques for growing hard nanostructured coatings: an overview 500
18.1 Introduction 500
18.2 Hard nanocoatings: from history to designs and properties 502
18.2.1 Classifications of hard nanocoatings 504
18.2.2 Hardness mechanisms of crystalline nanostructured materials 506
18.3 Main plasma-based techniques for synthesis of hard nanocoatings 507
18.3.1 Physical vapor deposition 508
18.3.2 Chemical vapor deposition 511
18.3.2.1 Advantages 516
18.3.2.2 Disadvantages 516
18.3.3 Atomic layer deposition 516
18.3.3.1 Deposition technique 516
18.3.3.2 Applications of ALD hard coatings 518
18.4 Conclusion 519
Acknowledgments 519
References 520
19 Thermal spray nanostructured ceramic and metal-matrix composite coatings 526
19.1 Introduction 526
19.1.1 Wear resistance and nanostructured materials 526
19.1.2 Thermal and cold spray 527
19.2 Nanostructured feedstock 529
19.3 Nanostructured coatings 535
19.3.1 Ceramic 535
19.3.2 MMC 540
19.4 Proven applications 542
19.4.1 Nanostructured alumina-titania coating for US Navy applications 542
19.4.2 Nanostructured titania coating for hydrometallurgical applications 543
19.5 Possible future applications 545
19.5.1 Ceramics 545
19.5.2 MMCs 547
19.6 Summary 550
Acknowledgements 551
References 551
20 Thermally sprayed nanostructured coatings for anti-wear and TBC applications: state-of-the-art and future perspectives 558
20.1 Introduction 558
20.2 Thermal spraying processes 559
20.2.1 HVOF spraying 560
20.2.2 Plasma spraying 560
20.3 Typical nanostructured coatings for technological applications 561
20.3.1 Cermet coatings for anti-wear applications 562
20.3.2 Alumina-titania composite coatings for anti-wear applications 570
20.3.3 Ceramic thermal barrier coatings 575
20.4 Conclusion 582
References 582
21 Hard thin films: applications and challenges 588
21.1 Introduction 588
21.2 Characterization of thin films 590
21.2.1 Diamond and diamond-related films 590
21.2.1.1 Properties and productions 590
21.2.1.2 Applications 592
21.2.1.2.1 Cutting tools and wear components 592
21.2.1.2.2 Optical windows 593
21.2.1.2.3 Biomedical components 593
21.2.1.2.4 Thermal management and electronic devices 594
21.2.2 Semiconductor hard thin films 595
21.2.2.1 AlN film 595
21.2.2.1.1 Properties and productions 595
21.2.2.1.2 Applications 596
21.2.2.2 GaAs film 598
21.2.2.2.1 Properties and production 598
21.2.3 Metallic glass thin film 600
21.2.3.1 Properties and production 601
21.2.3.2 Applications 603
21.2.3.2.1 MEMS/NEMS 603
21.2.3.2.2 Thermal replication 604
21.2.3.2.3 Biomedical tools 604
21.2.3.2.4 Protective coatings 605
21.3 Challenges 605
21.3.1 Residual stress 605
21.3.2 Surface roughness 607
21.4 Summary 607
References 608
Index 614