Page 6 - Tribology in Machine Design

Contents

Preface xi

1. Introduction to the concept of tribodesign 1
1.1. Specific principles of tribodesign 4
1.2. Tribological problems in machine design 6
1.2.1. Plain sliding bearings 6
1.2.2. Rolling contact bearings 7
1.2.3. Piston, piston rings and cylinder liners 8
1.2.4. Cam and cam followers 9
1.2.5. Friction drives 10
1.2.6. Involute gears 10
1.2.7. Hypoid gears 11
1.2.8. Worm gears 12
2. Basic principles of tribology 13
2.1. Origins of sliding friction 13
2.2 Contact between bodies in relative motion 14
2.3 Friction due to adhesion 15
2.4. Friction due to ploughing 16
2.5. Friction due to deformation 17
2.6 Energy dissipation during friction 18
2.7 Friction under complex motion conditions 18
2.8. Types of wear and their mechanisms 19
2.8.1. Adhesive wear 19
2.8.2. Abrasive wear 20
2.8.3. Wear due to surface fatigue 21
2.8.4. Wear due to chemical reactions 22
2.9. Sliding contact between surface asperities 23
2.10. The probability of surface asperity contact 26
2.11. Wear in lubricated contacts 31
2.11.1. Rheological lubrication regime 33
2.11.2. Functional lubrication regime 33
2.11.3. Fractional film defect 34
2.11.4. Load sharing in lubricated contacts 37
2.11.5. Adhesive wear equation 39
2.11.6. Fatigue wear equation 40
2.11.7. Numerical example 41