Multiscale Dissipative Mechanisms and Hierarchical Surfaces - Friction, Superhydrophobicity, and Biomimetics

Preface

Contents

Nomenclature

Glossary

Abbreviations

Part I Surface Roughness and Hierarchical Friction Mechanisms

1 Introduction

1.1 Surfaces and Surface Free Energy

1.2 Mesoscale

1.3 Hierarchy

1.4 Dissipation

1.5 Tribology

1.6 Biomimetics: From Engineering to Biology and Back

2 Rough Surface Topography

2.1 Rough Surface Characterization

2.2 Statistical Analysis of Random Surface Roughness

2.3 Fractal Surface Roughness

2.4 Contact of Rough Solid Surfaces

2.5 Surface Modi.cation

2.6 Summary

3 Mechanisms of Dry Friction, Their Scaling and Linear Properties

3.1 Approaches to the Multiscale Nature of Friction

3.2 Mechanisms of Dry Friction

3.3 Friction as a Linear Phenomenon

3.4 Summary

4 Friction as a Nonlinear Hierarchical Phenomenon

4.1 Nonlinear Effects in Dry Friction

4.2 Nonlinearity and Hierarchy

4.3 Heterogeneity, Hierarchy and Energy Dissipation

4.4 Mapping of Friction at Various Hierarchy Levels

4.5 Summary

Part II Solid–Liquid Friction and Superhydrophobicity

5 Solid–Liquid Interaction and Capillary Effects

5.1 Three Phase States of Matter

5.2 Phase Equilibrium and Stability

5.3 Water Phase Diagram at the Nanoscale

5.4 Surface Free Energy and the Laplace Equation

5.5 Contact Angle and the Young Equation

5.6 Kelvin’s Equation

5.7 Capillary Effects and Stability Issues

5.8 Summary

6 Roughness-Induced Superhydrophobicity

6.1 The Phenomenon of Superhydrophobicity

6.2 Contact Angle Analysis

6.3 Heterogeneous Surfaces and Wenzel and Cassie Equations

6.4 Calculation of the Contact Angle for Selected Surfaces

6.5 Contact Angle Hysteresis

6.6 Summary

7 Stability of the Composite Interface, Roughness Optimization and Meniscus Force

7.1 Destabilization of the Composite Interface

7.2 Contact Angle with Three-Dimensional Solid Harmonic Surface

7.3 Capillary Adhesion Force Due to the Meniscus

7.4 Roughness Optimization

7.5 Effect of the Hierarchical Roughness

7.6 Summary

8 Cassie–Wenzel Wetting Regime Transition

8.1 The Cassie–Wenzel Transition and the Contact Angle Hysteresis

8.2 Experimental Study of the Cassie–Wenzel Transition

8.3 Wetting as a Multiscale Phenomenon

8.4 Investigation ofWetting as a Phase Transition

8.5 Reversible Superhydrophobicity

8.6 Summary

9 Underwater Superhydrophobicity and Dynamic Effects

9.1 Superhydrophobicity for the Liquid Flow

9.2 Nanobubbles and Hydrophobic Interaction

9.3 Bouncing Droplets

9.4 A Droplet on a Hot Surface: the Leidenfrost Effect

9.5 A Droplet on an Inclined Surface

9.6 Summary

Part III Biological and Biomimetic Surfaces

10 Lotus-Effect and Water-Repellent Surfaces in Nature

10.1 Water-Repellent Plants

10.2 Characterization of Hydrophobic and Hydrophilic Leaf Surfaces

10.3 Other Biological Superhydrophobic Surfaces

10.4 Summary

11 Artificial (Biomimetic) Superhydrophobic Surfaces

11.1 How to Make a Superhydrophobic Surface

11.2 Experimental Techniques

11.3 Wetting of Micro- and Nanopatterned Surfaces

11.4 Self-cleaning

11.5 Commercially Available Lotus-Effect Products

11.6 Summary

12 Gecko-Effect and Smart Adhesion

12.1 Gecko

12.2 Hierarchical Structure of the Attachment Pads

12.3 Model of Hierarchical Attachment Pads

12.4 Biomimetic Fibrillar Structures

12.5 Self-cleaning

12.6 Biomimetic Tape Made of Arti.cial Gecko Skin

12.7 Summary

13 Other Biomimetic Surfaces

13.1 Hierarchical Organization in Biomaterials

13.2 Moth-Eye-Effect

13.3 Shark Skin

13.4 Darkling Beetle

13.5 Water Strider

13.6 Spider Web

13.7 Other Biomimetic Examples

13.8 Summary

14 Outlook

References

Index