Principles of Tribology, 2nd Edition

Updated to include the timely and important topics of MEMS and rolling friction, Principles of Tribology is a compilation of current developments from tribology research, coupled with tribology fundamentals and applications. Essential topics include lubrication theory, lubrication design, friction mechanism, wear mechanism, friction control, and their applications. Besides classical tribology content, the book also covers intersecting research areas of tribology, as well as the regularities and characteristics of the tribological phenomena in practice. Furthermore, it presents the basic theory, numerical analysis methods and experimental measuring techniques of tribology as well as their application in engineering.

• Newly expanded and updated to include new tribological material on MEMS and green tribology, its key concepts and applications
• Systematically brings the reader through fundamental theories, basic mechanisms through to the latest research
• Emphasizes practical tribological phenomena, supported by numerical analysis and experimental measurement techniques
• Discusses nano-tribology, thin film lubrication and its applications, topics which are growing in importance

A comprehensive look at the fundamentals and latest research, this second edition of Principles of Tribology is an essential textbook for graduate and senior undergraduate students specializing in tribology and related mechanical engineering fields.

Auteur
SHIZHU WEN, Tsinghua University, China PING HUANG, South China University of Technology, China

Contenu
About the Authors xxi Second Edition Preface xxiii Preface xxv Introduction xxvii Part I Lubrication Theory 1 1 Properties of Lubricants 3 1.1 Lubrication States 3 1.2 Density of Lubricant 5 1.3 Viscosity of Lubricant 7 1.3.1 Dynamic Viscosity and Kinematic Viscosity 7 1.3.2 Relationship between Viscosity and Temperature 9 1.3.3 Relationship between Viscosity and Pressure 10 1.4 Non-Newtonian Behaviors 12 1.4.1 Ree-Eyring Constitutive Equation 12 1.4.2 Visco-Plastic Constitutive Equation 13 1.4.3 Circular Constitutive Equation 13 1.4.4 Temperature-Dependent Constitutive Equation 13 1.4.5 Visco-Elastic Constitutive Equation 14 1.4.6 Nonlinear Visco-Elastic Constitutive Equation 14 1.4.7 A Simple Visco-Elastic Constitutive Equation 15 1.5 Wettability of Lubricants 16 1.5.1 Wetting and Contact Angle 17 1.5.2 Surface Tension 17 1.6 Measurement and Conversion of Viscosity 19 1.6.1 Rotary Viscometer 19 1.6.2 Off-Body Viscometer 19 1.6.3 Capillary Viscometer 19 References 21 2 Basic Theories of Hydrodynamic Lubrication 22 2.1 Reynolds Equation 22 2.1.1 Basic Assumptions 22 2.1.2 Derivation of the Reynolds Equation 23 2.2 Hydrodynamic Lubrication 26 2.2.1 Mechanism of Hydrodynamic Lubrication 26 2.2.2 Boundary Conditions and Initial Conditions of the Reynolds Equation 27 2.2.3 Calculation of Hydrodynamic Lubrication 28 2.3 Elastic Contact Problems 29 2.3.1 Line Contact 29 2.3.2 Point Contact 31 2.4 Entrance Analysis of EHL 34 2.4.1 Elastic Deformation of Line Contacts 35 2.4.2 Reynolds Equation Considering the Effect of Pressure-Viscosity 35 2.4.3 Discussion 36 2.4.4 Grubin FilmThickness Formula 37 2.5 Grease Lubrication 38 References 40 3 Numerical Methods of Lubrication Calculation 41 3.1 Numerical Methods of Lubrication 42 3.1.1 Finite Difference Method 42 3.1.2 Finite Element Method and Boundary Element Method 48 3.1.3 Numerical Techniques 51 3.2 Numerical Solution of the Energy Equation 54 3.2.1 Conduction and Convection of Heat 55 3.2.2 Energy Equation 56 3.2.3 Numerical Solution of Energy Equation 59 3.3 Numerical Solution of Elastohydrodynamic Lubrication 60 3.3.1 EHL Numerical Solution of Line Contacts 60 3.3.2 EHL Numerical Solution of Point Contacts 64 3.4 Multi-Grid Method for Solving EHL Problems 68 3.4.1 Basic Principles of Multi-Grid Method 68 3.4.2 Nonlinear Full Approximation Scheme for the Multi-Grid Method 69 3.4.3 V andWIterations 71 3.4.4 Multi-Grid Solution of EHL Problems 71 3.4.5 Multi-Grid Integration Method 73 References 76 4 Lubrication Design of Typical Mechanical Elements 78 4.1 Slider and Thrust Bearings 78 4.1.1 Basic Equations 78 4.1.2 Solutions of Slider Lubrication 79 4.2 Journal Bearings 81 4.2.1 Axis Position and Clearance Shape 81 4.2.2 Infinitely Narrow Bearings 82 4.2.3 InfinitelyWide Bearings 85 4.3 Hydrostatic Bearings 88 4.3.1 Hydrostatic Thrust Plate 89 4.3.2 Hydrostatic Journal Bearings 90 4.3.3 Bearing Stiffness andThrottle 90 4.4 Squeeze Bearings 92 4.4.1 Rectangular Plate Squeeze 93 4.4.2 Disc Squeeze 94 4.4.3 Journal Bearing Squeeze 94 4.5 Dynamic Bearings 96 4.5.1 Reynolds Equation of Dynamic Journal Bearings 96 4.5.2 Simple Dynamic Bearing Calculation 98 4.5.3 General Dynamic Bearings 100 4.6 Gas Lubrication Bearings 102 4.6.1 Basic Equations of Gas Lubrication 102 4.6.2 Types of Gas Lubrication Bearings 103 4.7 Rolling Contact Bearings 106 4.7.1 Equivalent Radius R 107 4.7.2 Average Velocity U 107 4.7.3 Carrying Load PerWidthW/b 107 4.8 Gear Lubrication 108 4.8.1 Involute Gear Transmission 109 4.8.2 Arc Gear Transmission EHL 112 4.9 Cam Lubrication 114 References 116 5 Special Fluid Medium Lubrication 118 5.1 Magnetic Hydrodynamic Lubrication 118 5.1.1 Composition and Classification of Magnetic Fluids 118 5.1.2 Properties of Magnetic Fluids 119 5.1.3 Basic Equations of Magnetic Hydrodynamic Lubrication 121 5.1.4 Influence Factors on Magnetic EHL 123 5.2 Micro-Polar Hydrodynamic Lubrication 124 5.2.1 Basic Equations of Micro-Polar Fluid Lubrication 124 5.2.2 Influence Factors on Micro-Polar Fluid Lubrication 128 5.3 Liquid Crystal Lubrication 130 5.3.1 Types of Liquid Crystal 130 5.3.2 Deformation Analysis of Liquid Crystal Lubrication 132 5.3.3 Friction Mechanism of Liquid Crystal as a Lubricant Additive 136 5.4 Electric Double Layer Effect inWater Lubrication 137 5.4.1 Electric Double Layer Hydrodynamic Lubrication Theory 138 5.4.2 Influence of Electric Double Layer on Lubrication Properties 142 References 145 6 Lubrication Transformation and Nanoscale Thin Film Lubrication 147 6.1 Transformations of Lubrication States 147 6.1.1 Thickness-Roughness Ratio 147 6.1.2 Transformation from Hydrodynamic Lubrication to EHL 148 6.1.3 Transformation from EHL to Thin Film Lubrication 149 6.2 Thin Film Lubrication 152 6.2.1 Phenomenon ofThin Film Lubrication 153 6.2.2 Time Effect of Thin Film Lubrication 154 6.2.3 Shear Strain Rate Effect onThin Film Lubrication 157 6.3 Analysis ofThin Film Lubrication 158 6.3.1 Difficulties in Numerical Analysis of Thin Film Lubrication 158 6.3.2 Tichy's Thin Film Lubrication Models 160 6.4 Nano-Gas Film Lubrication 161 6.4.1 Rarefied Gas Effect 162 6.4.2 Boundary Slip 163 6.4.3 Reynolds Equation Considering the Rarefied Gas Effect 165 6.4.4 Calculation of Magnetic Head/Disk of UltraThin Gas Lubrication 166 References 169 7 Boundary Lubrication and Additives 171 7.1 Types of Boundary Lubrication 171 7.1.1 Stribeck Curve 171 7.1.2 Adsorption Films and Their Lubrication Mechanisms 172 7.1.3 Chemical Reaction Film and its Lubrication Mechanism 177 7.1.4 Other Boundary Films and their Lubrication Mechanisms 179 7.2 Theory of Boundary Lubrication 179 7.2.1 Boundary Lubrication Model 179 7.2.2 Factors Influencing Performance of Boundary Films 181 7.2.3 Strength of Boundary Film 184 7.3 Lubricant Additives 185 7.3.1 Oily Additives 185 7.3.2 Tackifier 186 7.3.3 Extreme Pressure Additives (EP Additives) 187 7.3.4 Anti-Wear Additives 187 7.3.5 Other Additives 187 References 189 8 Lubrication Failure and Mixed Lubrication 190 8.1 Roughness and Viscoelastic Material Effects on Lubrication 190 8.1.1 Modifications of Micro-EHL 190 8.1.2 Viscoelastic Model 191 8.1.3 LubricatedWear 192 8.2 Influence of Limit Shear Stress on Lubrication Failure 195 8.2.1 Visco-Plastic Constitutive Equation 195 8.2.2 Slip of Fluid-Solid Interface 196 8.2.3 Influence of Slip on Lubrication Properties 196 8.3 Influence of Temperature on Lubrication Fai…