Principles of Tribology

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.

Autorentext

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

Inhalt
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

1.3.1.1 Dynamic Viscosity 7

1.3.1.2 Kinematic Viscosity 8

1.3.2 Relationship between Viscosity and Temperature 9

1.3.2.1 ViscosityTemperature Equations 9

1.3.2.2 ASTM ViscosityTemperature Diagram 9

1.3.2.3 Viscosity Index 10

1.3.3 Relationship between Viscosity and Pressure 10

1.3.3.1 Relationships between Viscosity, Temperature and Pressure 11

1.4 Non-Newtonian Behaviors 12

1.4.1 ReeEyring 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

1.4.7.1 Pseudoplasticity 16

1.4.7.2 Thixotropy 16

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

2.1.2.1 Force Balance 23

2.1.2.2 General Reynolds Equation 25

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

2.2.2.1 Boundary Conditions 27

2.2.2.2 Initial Conditions 28

2.2.3 Calculation of Hydrodynamic Lubrication 28

2.2.3.1 Load-Carrying CapacityW 28

2.2.3.2 Friction ForceF 28

2.2.3.3 Lubricant FlowQ 29

2.3 Elastic Contact Problems 29

2.3.1 Line Contact 29

2.3.1.1 Geometry and Elasticity Simulations 29

2.3.1.2 Contact Area and Stress 30

2.3.2 Point Contact 31

2.3.2.1 Geometric Relationship 31

2.3.2.2 Contact Area and Stress 32

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

3.1.1.1 Hydrostatic Lubrication 44

3.1.1.2 Hydrodynamic Lubrication 44

3.1.2 Finite Element Method and Boundary Element Method 48

3.1.2.1 Finite Element Method (FEM) 48

3.1.2.2 Boundary Element Method 49

3.1.3 Numerical Techniques 51

3.1.3.1 Parameter Transformation 51

3.1.3.2 Numerical Integration 51

3.1.3.3 Empirical Formula 53

3.1.3.4 SuddenThickness Change 53

3.2 Numerical Solution of the Energy Equation 54

3.2.1 Conduction and Convection of Heat 55

3.2.1.1 Conduction Heat Hd 55

3.2.1.2 Convection Heat Hv 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

3.3.1.1 Basic Equations 60

3.3.1.2 Solution of the Reynolds Equation 62 3.3.1.3 Calculation of Elastic De...