Engineering Tribology, Second Edition

The field of tribology encompasses knowledge drawn from the disciplines of mechanical engineering, materials science, chemistry and physics. The control of friction and wear, the aim of the subject, is comprehensively and accessibly addressed in this 2nd edition of Engineering Tribology. This interdisciplinary approach has proven to be a very successful way of analyzing friction and wear problems. In conjunction with this 2nd Edition, MATLAB computer programs will be accessible for practical applications via the Butterworth-Heinemann website. A basic feature of Engineering Tribology 2nd Edition is the emphasis on describing various concepts in an accessible manner for the benefit of non-specialists. This principle is applied from the beginning of the book, where the reader is introduced to the fundamental concept of tribology. This concept is then used to show how the various topics in tribology are interrelated to form one coherent subject. A direct graphical illustration of the mechanisms controlling tribological phenomena is presented. Carefully prepared diagrams allow rapid appreciation of the basic ideas and facts in tribology. The numerical analysis of hydrodynamic lubrication is supported by a number of computer programs which are included in the book. The control of wear is given extensive treatment with a thorough discussion of lubricant additives, solid lubricants and surface coatings. The effectiveness of coatings in suppressing specific forms of wear is analyzed together with the methods of coatings deposition. More than 1000 references are provided to give the reader access to more specialized information if required. An essential aspect of all engineering industry Highly illustrated, comprehensive subject coverage Practical applications used as examples where appropriate Contents 7 Preface 24 Acknowledgements 25 1 Introduction 26 1.1 BACKGROUND 26 1.2 MEANING OF TRIBOLOGY 27 1.3 COST OF FRICTION AND WEAR 30 2 Physical properties of Lubricants 36 2.1 INTRODUCTION 36 2.2 OIL VISCOSITY 36 2.3 VISCOSITY TEMPERATURE RELATIONSHIP 38 2.4 VISCOSITY INDEX 40 2.5 VISCOSITY PRESSURE RELATIONSHIP 41 2.6 VISCOSITY-SHEAR RATE RELATIONSHIP 47 2.7 VISCOSITY MEASUREMENTS 49 2.8 VISCOSITY OF MIXTURES 55 2.9 OIL VISCOSITY CLASSIFICATION 56 2.10 LUBRICANT DENSITY AND SPECIFIC GRAVITY 58 2.11 THERMAL PROPERTIES OF LUBRICANTS 59 2.12 TEMPERATURE CHARACTERISTICS OF LUBRICANTS 60 2.13 OPTICAL PROPERTIES OF LUBRICANTS 68 2.14 ADDITIVE COMPATIBILITY AND SOLUBILITY 69 2.15 LUBRICANT IMPURITIES AND CONTAMINANTS 69 2.16 SOLUBILITY OF GASES IN OILS 70 2.17 SUMMARY 73 3 Lubricants and their Composition 76 3.1 INTRODUCTION 76 3.2 MINERAL OILS 77 3.3 SYNTHETIC OILS 82 3.4 EMULSIONS AND AQUEOUS LUBRICANTS 90 3.5 GREASES 91 3.6 LUBRICANT ADDITIVES 106 3.7 SUMMARY 121 4 Hydrodynamic Lubricantion 126 4.1 INTRODUCTION 126 4.2 REYNOLDS EQUATION 126 4.3 PAD BEARINGS 141 4.4 CONVERGING-DIVERGING WEDGES 162 4.5 JOURNAL BEARINGS 171 4.6 THERMAL EFFECTS IN BEARINGS 197 4.7 LIMITS OF HYDRODYNAMIC LUBRICATION 207 4.8 HYDRODYNAMIC LUBRICATION WITH NON-NEWTONIAN FLUIDS 209 4.9 REYNOLDS EQUATION FOR SQUEEZE FILMS 216 4.10 POROUS BEARINGS 221 4.11 SUMMARY 222 5 Computation Hydrodynamics 226 5.1 INTRODUCTION 226 5.2 NON-DIMENSIONALIZATION OF THE REYNOLDS EQUATION 226 5.3 THE VOGELPOHL PARAMETER 227 5.4 FINITE DIFFERENCE EQUIVALENT OF THE REYNOLDS EQUATION 229 5.5 NUMERICAL ANALYSIS OF HYDRODYNAMIC LUBRICATION IN IDEALIZED JOURNAL AND PARTIAL ARC BEARINGS 235 5.6 NUMERICAL ANALYSIS OF HYDRODYNAMIC LUBRICATION IN A REAL BEARING 241 5.7 SUMMARY 279 6 Hydrostatic Lubrication 282 6.1 INTRODUCTION 282 6.2 HYDROSTATIC BEARING ANALYSIS 283 6.3 GENERALIZED APPROACH TO HYDROSTATIC BEARING ANALYSIS 291 6.4 OPTIMIZATION OF HYDROSTATIC BEARING DESIGN 292 6.5 AEROSTATIC BEARINGS 300 6.6 HYBRID BEARINGS 303 6.7 STABILITY OF HYDROSTATIC AND AEROSTATIC BEARINGS 303 6.8 SUMMARY 304 7 Elastohydrodynamic Lubrication 306 7.1 INTRODUCTION 306 7. 2 CONTACT STRESSES 307 7.3 CONTACT BETWEEN TWO ELASTIC SPHERICAL OR SPHEROIDAL BODIES 309 7.4 ELASTOHYDRODYNAMIC LUBRICATING FILMS 330 7.5 MICRO-ELASTOHYDRODYNAMIC LUBRICATION AND MIXED OR PARTIAL EHL 347 7.6 SURFACE TEMPERATURE AT THE CONJUNCTION BETWEEN CONTACTING SOLIDS AND ITS EFFECT ON EHL 352 7.7 TRACTION AND EHL 368 7.8 SUMMARY 377 8 Boundary and Extreme Pressure Lubrication 382 8.1 INTRODUCTION 382 8.2 LOW TEMPERATURE - LOW LOAD LUBRICATION MECHANISMS 384 8.3 LOW TEMPERATURE - HIGH LOAD LUBRICATION MECHANISMS 385 8.4 HIGH TEMPERATURE - MEDIUM LOAD LUBRICATION MECHANISMS 406 8.5 HIGH TEMPERATURE - HIGH LOAD LUBRICATION MECHANISMS 413 8.6 BOUNDARY AND E.P. LUBRICATION OF NON-METALLIC SURFACES 429 8.7 SUMMARY 429 9 Solid Lubrication and Surface Treatments 436 9.1 INTRODUCTION 436 9.2 LUBRICATION BY SOLIDS 436 9.3 WEAR RESISTANT COATINGS AND SURFACE TREATMENTS 451 9.4 SUMMARY 467 10 Fundamentals of Contact Between Solids 472 10.1 INTRODUCTION 472 10.2 SURFACES OF SOLIDS 472 10.3 CONTACT BETWEEN SOLIDS 486 10.4 FRICTION AND WEAR 493 10.5 SUMMARY 503 REFERENCES 503 11 Abrasiv, Erosive and Cavitation Wear 508 11.1 INTRODUCTION 508 11.2 ABRASIVE WEAR 508 11.3 EROSIVE WEAR 534 11.4 CAVITATION WEAR 549 11.5 SUMMARY 551 12 Adhesion and Adhesive Wear 558 12.1 INTRODUCTION 558 12.2 MECHANISM OF ADHESION 558 12.3 CONTROL OF THE ADHESIVE WEAR 573 12.4 SUMMARY 575 13 Corrosive and Oxidative Wear 578 13.1 INTRODUCTION 578 13.2 CORROSIVE WEAR 578 13.3 OXIDATIVE WEAR 585 13.4 SUMMARY 592 14 Fatigue Wear 596 14.1 INTRODUCTION 596 14.2 FATIGUE WEAR DURING SLIDING 597 14.3 FATIGUE WEAR DURING ROLLING 604 14.4 MEANS OF CONTROLLING FATIGUE WEAR 614 14.5 SUMMARY 614 15 Fretting and Minor Wear Mechanisms 618 15.1 INTRODUCTION 618 15.2 FRETTING WEAR 619 15.3 MELTING WEAR 634 15.4 WEAR DUE TO ELECTRICAL DISCHARGES 636 15.5 DIFFUSIVE WEAR 637 15.6 IMPACT WEAR 638 15.7 SUMMARY 640 16 Wear of Non-Metallic Materials 644 16.1 INTRODUCTION 644 16.2 TRIBOLOGY OF POLYMERS 644 16.3 TRIBOLOGY OF POLYMER COMPOSITES 668 16.4 WEAR AND FRICTION OF CERAMICS 673 16.5 SUMMARY 688 Appendix 694 A1 USER FRIENDLY INTERFACE 695 A2 PROGRAM ‘VISCOSITY’ 0 A3 PROGRAM ‘SIMPLE’ 0 A4 PROGRAM ‘PARTIAL’ 0 A5 PROGRAM ‘THERMAL’ 0 A6 PROGRAM ‘DEFLECTION’ 0 A7 PROGRAM ‘GROOVE’ 0 A8 PROGRAM ‘STABILITY’ 0 Index 748 Referex Contents......Page 7 Preface......Page 24 Acknowledgements......Page 25 1.1 BACKGROUND......Page 26 1.2 MEANING OF TRIBOLOGY......Page 27 1.3 COST OF FRICTION AND WEAR......Page 30 2.2 OIL VISCOSITY......Page 36 2.3 VISCOSITY TEMPERATURE RELATIONSHIP......Page 38 2.4 VISCOSITY INDEX......Page 40 2.5 VISCOSITY PRESSURE RELATIONSHIP......Page 41 2.6 VISCOSITY-SHEAR RATE RELATIONSHIP......Page 47 2.7 VISCOSITY MEASUREMENTS......Page 49 2.8 VISCOSITY OF MIXTURES......Page 55 2.9 OIL VISCOSITY CLASSIFICATION......Page 56 2.10 LUBRICANT DENSITY AND SPECIFIC GRAVITY......Page 58 2.11 THERMAL PROPERTIES OF LUBRICANTS......Page 59 2.12 TEMPERATURE CHARACTERISTICS OF LUBRICANTS......Page 60 2.13 OPTICAL PROPERTIES OF LUBRICANTS......Page 68 2.15 LUBRICANT IMPURITIES AND CONTAMINANTS......Page 69 2.16 SOLUBILITY OF GASES IN OILS......Page 70 2.17 SUMMARY......Page 73 3.1 INTRODUCTION......Page 76 3.2 MINERAL OILS......Page 77 3.3 SYNTHETIC OILS......Page 82 3.4 EMULSIONS AND AQUEOUS LUBRICANTS......Page 90 3.5 GREASES......Page 91 3.6 LUBRICANT ADDITIVES......Page 106 3.7 SUMMARY......Page 121 4.2 REYNOLDS EQUATION......Page 126 4.3 PAD BEARINGS......Page 141 4.4 CONVERGING-DIVERGING WEDGES......Page 162 4.5 JOURNAL BEARINGS......Page 171 4.6 THERMAL EFFECTS IN BEARINGS......Page 197 4.7 LIMITS OF HYDRODYNAMIC LUBRICATION......Page 207 4.8 HYDRODYNAMIC LUBRICATION WITH NON-NEWTONIAN FLUIDS......Page 209 4.9 REYNOLDS EQUATION FOR SQUEEZE FILMS......Page 216 4.10 POROUS BEARINGS......Page 221 4.11 SUMMARY......Page 222 5.2 NON-DIMENSIONALIZATION OF THE REYNOLDS EQUATION......Page 226 5.3 THE VOGELPOHL PARAMETER......Page 227 5.4 FINITE DIFFERENCE EQUIVALENT OF THE REYNOLDS EQUATION......Page 229 5.5 NUMERICAL ANALYSIS OF HYDRODYNAMIC LUBRICATION IN IDEALIZED JOURNAL AND PARTIAL ARC BEARINGS......Page 235 5.6 NUMERICAL ANALYSIS OF HYDRODYNAMIC LUBRICATION IN A REAL BEARING......Page 241 5.7 SUMMARY......Page 279 6.1 INTRODUCTION......Page 282 6.2 HYDROSTATIC BEARING ANALYSIS......Page 283 6.3 GENERALIZED APPROACH TO HYDROSTATIC BEARING ANALYSIS......Page 291 6.4 OPTIMIZATION OF HYDROSTATIC BEARING DESIGN......Page 292 6.5 AEROSTATIC BEARINGS......Page 300 6.7 STABILITY OF HYDROSTATIC AND AEROSTATIC BEARINGS......Page 303 6.8 SUMMARY......Page 304 7.1 INTRODUCTION......Page 306 7. 2 CONTACT STRESSES......Page 307 7.3 CONTACT BETWEEN TWO ELASTIC SPHERICAL OR SPHEROIDAL BODIES......Page 309 7.4 ELASTOHYDRODYNAMIC LUBRICATING FILMS......Page 330 7.5 MICRO-ELASTOHYDRODYNAMIC LUBRICATION AND MIXED OR PARTIAL EHL......Page 347 7.6 SURFACE TEMPERATURE AT THE CONJUNCTION BETWEEN CONTACTING SOLIDS AND ITS EFFECT ON EHL......Page 352 7.7 TRACTION AND EHL......Page 368 7.8 SUMMARY......Page 377 8.1 INTRODUCTION......Page 382 8.2 LOW TEMPERATURE - LOW LOAD LUBRICATION MECHANISMS......Page 384 8.3 LOW TEMPERATURE - HIGH LOAD LUBRICATION MECHANISMS......Page 385 8.4 HIGH TEMPERATURE - MEDIUM LOAD LUBRICATION MECHANISMS......Page 406 8.5 HIGH TEMPERATURE - HIGH LOAD LUBRICATION MECHANISMS......Page 413 8.7 SUMMARY......Page 429 9.2 LUBRICATION BY SOLIDS......Page 436 9.3 WEAR RESISTANT COATINGS AND SURFACE TREATMENTS......Page 451 9.4 SUMMARY......Page 467 10.2 SURFACES OF SOLIDS......Page 472 10.3 CONTACT BETWEEN SOLIDS......Page 486 10.4 FRICTION AND WEAR......Page 493 REFERENCES......Page 503 11.2 ABRASIVE WEAR......Page 508 11.3 EROSIVE WEAR......Page 534 11.4 CAVITATION WEAR......Page 549 11.5 SUMMARY......Page 551 12.2 MECHANISM OF ADHESION......Page 558 12.3 CONTROL OF THE ADHESIVE WEAR......Page 573 12.4 SUMMARY......Page 575 13.2 CORROSIVE WEAR......Page 578 13.3 OXIDATIVE WEAR......Page 585 13.4 SUMMARY......Page 592 14.1 INTRODUCTION......Page 596 14.2 FATIGUE WEAR DURING SLIDING......Page 597 14.3 FATIGUE WEAR DURING ROLLING......Page 604 14.5 SUMMARY......Page 614 15.1 INTRODUCTION......Page 618 15.2 FRETTING WEAR......Page 619 15.3 MELTING WEAR......Page 634 15.4 WEAR DUE TO ELECTRICAL DISCHARGES......Page 636 15.5 DIFFUSIVE WEAR......Page 637 15.6 IMPACT WEAR......Page 638 15.7 SUMMARY......Page 640 16.2 TRIBOLOGY OF POLYMERS......Page 644 16.3 TRIBOLOGY OF POLYMER COMPOSITES......Page 668 16.4 WEAR AND FRICTION OF CERAMICS......Page 673 16.5 SUMMARY......Page 688 Appendix......Page 694 A1 USER FRIENDLY INTERFACE......Page 695 A8 PROGRAM ‘STABILITY’......Page 0 Index......Page 748 "This book provides a valuable insight into an important yet obscure subject where there are few available guides. The reader is first introduced to the fundamental concept of tribology. This concept is then used to show how the various topics in tribology are interrelated to form one coherent subject. Illustrations are widely used throughout the book to assist readers in grasping the fundamental tribological concepts. Mechanisms of wear, friction and lubrication are comprehensively described in an accessible manner that is designed to be helpful to non-specialists. The control of wear is given extensive treatment with a thorough discussion of lubricant additives, solid lubricants and surface coatings. The effectiveness of coatings in suppressing specific forms of wear is described together with the methods of coating deposition. More than 1000 references are provided to give the reader access to more specialized information if required. The numerical analysis of hydrodynamic lubrication is supported by a number of computer programs, written in Matlab, which enable the readers to quantitatively analyze lubrication problems. A careful study of the book will not only enable the readers to understand what tribology is, but also to comprehend how it can be applied to solve problems of mechanical failure, reduce maintenance costs and lower the energy consumption."--BOOK JACKET. The field of tribology encompasses knowledge drawn from the disciplines of mechanical engineering, materials science, chemistry and physics. This book addresses the control of friction and wear; and places emphasis on describing various concepts for the benefit of non-specialists.