1 Introduction ................................................. 1
1.1 Self-Healing in Materials Science and Engineering ....... 1
1.2 Surface Science and Tribology ........................... 4
1.3 Nonequilibrium Thermodynamics and Self-Organization ..... 8
1.3.1 Classical Thermodynamic Potentials ............... 8
1.3.2 Nonequilibrium Thermodynamics ................... 11
1.3.3 Self-Organization ............................... 13
1.4 Self-Organization During Friction ...................... 14
1.4.1 Frictional Dynamic Effects ...................... 16
1.5 Composite Materials for Tribological Applications ...... 17
1.6 Biomimetics ............................................ 18
1.7 Summary ................................................ 22
Part I Self-Healing Materials
2 Thermodynamic Principles of Self-Healing Metallic
Materials ................................................... 25
2.1 Introduction ........................................... 25
2.2 Thermodynamics of Self-Healing ......................... 28
2.2.1 Entropy of a Hierarchical System ................ 28
2.2.2 Thermodynamic Forces that Drive Healing ......... 30
2.2.3 Friction-Induced Degradation .................... 32
2.2.4 Optimization of Healing ......................... 34
2.3 Self-Healing Metallic Systems .......................... 35
2.3.1 Damage Prevention by Precipitation in Under-
Aged Alloys ..................................... 36
2.3.2 Composite Materials Reinforced with Shape-
Memory Alloys ................................... 40
2.3.3 Composite Materials Reinforced with a Healing
Agent ........................................... 44
2.4 Future Approaches ...................................... 48
2.5 Summary ................................................ 50
3 Case Study of Self-Healing in Metallic Composite with
Embedded Low Melting Temperature Solders .................... 53
3.1 Introduction ........................................... 53
3.2 Modeling Self-Healing .................................. 55
3.2.1 Multiscale Effects of Crystal Grain Growth ...... 55
3.2.2 Multiscale Nature of Degradation and Healing .... 61
3.2.3 Healing Agent Release by Fracture ............... 66
3.2.4 Healing Agent Release by Heating and Melting .... 67
3.3 Entropy, Degradation, and Healing Rates During Self-
Healing ................................................ 68
3.3.1 Entropy and Degradation ......................... 68
3.3.2 Degradation and Healing ......................... 69
3.4 Validation of the Model for Self-Healing Al Alloy ...... 71
3.5 Summary ................................................ 73
4 Surface Healing: A Case Study ............................... 75
4.1 Introduction ........................................... 75
4.2 Self-Organization at the Sliding Interface ............. 76
4.3 Self-Healing at the Interface .......................... 78
4.4 Self-Healing of Voids in Plant Surfaces ................ 83
4.5 Summary ................................................ 84
5 Development of Metallic and Metal Matrix Composite Self-
Healing Materials ........................................... 87
5.1 Self-Healing Solders ................................... 87
5.1.1 Composition of Solders .......................... 87
5.1.2 Partial Melting and Solidification .............. 89
5.1.3 Shape Memory Alloy-Based Healing of a Solder .... 90
5.1.4 Eutectic-Based Healing .......................... 91
5.1.5 Low Melting Point Alloy in Hollow
Reinforcement ................................... 93
5.2 Off-Eutectic Healing System ............................ 94
5.3 Tests of Mechanical Properties ......................... 96
5.4 Shape Memory Alloy-Based Healing System ................ 98
5.5 Healing by Low Melting Point Alloy Contained in
Hollow Reinforcement .................................. 101
5.6 Precipitations of Supersaturated Solid Solution ....... 103
5.7 Experimental Studies and Simulation with Account
for the Effects of Gravity and Capillarity ............ 105
5.8 Summary ............................................... 122
Part II Self-Lubricating Materials
6 Friction, Wear, and Self-Lubrication ....................... 125
6.1 Friction and Wear as Manifestations of the Second
Law of Thermodynamics ................................. 125
6.2 Contact of Rough Solid Surfaces ....................... 127
6.3 Dry Friction and Its Laws ............................. 131
6.4 Theories Explaining Dry Friction ...................... 133
6.4.1 Adhesive Friction .............................. 134
6.4.2 Deformation of Asperities ...................... 136
6.4.3 Plastic Yield .................................. 137
6.4.4 Fracture ....................................... 138
6.4.5 Ratchet and Cobblestone Mechanisms ............. 138
6.4.6 "Third-Body" Mechanism ......................... 138
6.4.7 Origins of the Linearity of Friction ........... 139
6.5 Wear .................................................. 144
6.6 Lubrication ........................................... 145
6.7 Self-Lubrication ...................................... 146
6.8 Summary ............................................... 151
7 Thermodynamic Methods in Tribology and Friction-Induced
Self-Organization .......................................... 153
7.1 Introduction .......................................... 154
7.2 Entropic Methods of Study of Self-Organized
Tribological Systems .................................. 157
7.2.1 Qualitative Studies ............................ 158
7.2.2 Entropy During Friction and Dissipation ........ 160
7.2.3 Thermally Activated Self-Organization .......... 162
7.2.4 The Concept of "Selective Transfer" ............ 166
7.2.5 The Concept of "Tribofatigue" .................. 167
7.3 Friction-Induced Self-Organization .................... 169
7.3.1 Running-In ..................................... 169
7.3.2 Feedback Loop Model for the Running-In ......... 173
7.3.3 Self-Organized Elastic Structures .............. 178
7.3.4 The Problems of Combining Friction with
Dynamics and Linear Elasticity ................. 181
7.3.5 SOC and Avalanche Dynamics ..................... 182
7.3.6 Pattern Formation and Turing systems ........... 184
7.4 Summary ............................................... 193
8 Tribological Properties of Metal Matrix Composites ......... 195
8.1 Introduction .......................................... 195
8.2 Manufacturing Methods of MMC .......................... 199
8.2.1 Powder Metallurgy .............................. 199
8.2.2 Casting ........................................ 200
8.2.3 Spray Deposition ............................... 200
8.3 Theoretical Basis for Understanding Friction
and Wear Behavior in Composites ....................... 201
8.3.1 Friction and Thin Film Lubrication in Metal
Matrix-Graphite Particle Composites ............ 201
8.3.2 Wear in Composites Containing Solid
Lubricants ..................................... 203
8.4 Friction, Wear, and Seizure Behavior of Graphite
Bearing Composites .................................... 205
8.4.1 Friction Characteristics ....................... 205
8.4.2 Wear Characteristics ........................... 209
8.4.3 Seizure Characteristics ........................ 215
8.5 Effect of Environmental Factors on Friction and Wear .. 216
8.5.1 Environmental Conditions and Lubrication ....... 216
8.5.2 Wear in Electrical Contacts .................... 218
8.5.3 Film Formation ................................. 221
8.6 Industrial Applications ............................... 224
8.7 Development of New Graphite Reinforced MMC Materials .. 227
8.8 The Role of Solid Lubricants .......................... 232
8.8.1 General Considerations ......................... 232
8.8.2 Nanoparticle and Microparticle Lubricants ...... 232
8.8.3 Graphene and Diamond Carbon Additives .......... 233
8.9 Summary ............................................... 234
Part III Self-Cleaning Materials
9 Thermodynamic Foundations of Wetting and Capillary
Phenomena .................................................. 239
9.1 The Solid, Liquid, and Vapor Phases of Matter ......... 240
9.2 Phase Equilibrium ..................................... 241
9.3 Negative Pressure and Disjoining Pressure in
Nanoscale Capillary Bridges ........................... 244
9.4 Water-Phase Diagram at the Nanoscale .................. 249
9.5 Laplace Equation ...................................... 252
9.6 Young Equation ........................................ 254
9.7 Kelvin's Equation ..................................... 258
9.8 Osmosis and Osmotic Pressure .......................... 260
9.9 Capillary Effects During Contacts of Rough Surfaces
and Stability Issues .................................. 262
9.9.1 Shape of the Meniscus .......................... 264
9.9.2 Capillary Force ................................ 266
9.10 Summary ............................................... 273
10 Superhydrophobicity ........................................ 275
10.1 Contact Angle with a Rough or Heterogeneous Surface ... 275
10.1.1 The Wenzel and Cassie Equations ................ 276
10.1.2 Limits of Applicability of the Wenzel and
Cassie Equations ............................... 278
10.2 Contact Angle Hysteresis .............................. 284
10.2.1 Causes of the Contact Angle Hysteresis ......... 284
10.2.2 Pinning of the Triple Line ..................... 285
10.2.3 Contact angle Hysteresis and the Adhesion
Hysteresis ..................................... 286
10.2.4 Simulation and Semiempirical Models ............ 289
10.3 The Cassie-Wenzel Transition .......................... 290
10.4 Effect of the Hierarchical Roughness .................. 296
10.4.1 Wetting as a Multiscale Phenomenon ............. 296
10.4.2 Hierarchical Roughness ......................... 298
10.4.3 Stability of a Composite Interface and
Hierarchical Roughness ......................... 300
10.5 Reversible Superhydrophobicity ........................ 308
10.6 A Droplet on an Inclined Surface ...................... 311
10.7 Bouncing-Off Droplets ................................. 312
10.8 Summary ............................................... 317
11 Lotus Effect and Self-Cleaning ............................. 319
11.1 Superhydrophobicity in Natural and Biomimetic
Surfaces .............................................. 319
11.2 Superhydrophobic Plant Leaves ......................... 325
11.3 Rose Petal Effect ..................................... 326
11.4 Insect and Bird Wings ................................. 332
11.5 Lotus-Effect-Based Self-Cleaning ...................... 334
11.6 Titania-Based Superhydrophilic Self-Cleaning .......... 335
11.7 Applications of Self-Cleaning Surfaces ................ 336
11.8 Deicing and Icephobicity .............................. 338
11.9 Summary ............................................... 341
12 Self-Cleaning in the Water Flow ............................ 343
12.1 Liquid Flow Near a Superhydrophobic Surface ........... 344
12.2 Nanobubbles and Hydrophobic Interaction ............... 346
12.3 Antifouling ........................................... 347
12.4 Underwater Oleophobicity .............................. 348
12.5 Polymeric Materials, Filters, and Desalination ........ 351
12.6 Summary ............................................... 353
13 Artificial Self-Cleaning Surfaces .......................... 355
13.1 Techniques to Make a Superhydrophobic Surface ......... 355
13.1.1 Roughening to Create One-level Structure ....... 356
13.1.2 Coating to Create Hydrophobic Structures ....... 359
13.2 Methods to Create Hierarchical Superhydrophobic
Structures ............................................ 360
13.3 MMC-Based Sustainable Superhydrophobic Surfaces ....... 361
13.3.1 Modeling of Wetting of Composite Materials ..... 362
13.3.2 Experimental ................................... 364
13.4 Polymeric Superhydrophobic Surfaces ................... 368
13.5 Summary ............................................... 370
14 Outlook .................................................... 375
About the Authors ............................................. 379
References .................................................... 381
Index ......................................................... 409
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