Admin مدير المنتدى
عدد المساهمات : 19001 التقييم : 35505 تاريخ التسجيل : 01/07/2009 الدولة : مصر العمل : مدير منتدى هندسة الإنتاج والتصميم الميكانيكى
| موضوع: كتاب Engineering Tribology الأربعاء 05 فبراير 2014, 7:58 pm | |
|
أخوانى فى الله أحضرت لكم كتاب
Engineering Tribology 2E Gwidon W. Stachowiak Department of Mechanical and Materials Engineering, University of Western Australia, Australia Andrew W. Batchelor Department of Mechanical and Materials Engineering, University of Western Australia, Australia
ويتناول الموضوعات الأتية :
1 INTRODUCTION 1 1.1 Background 1 1.2 Meaning of tribology 2 Lubrication 3 Wear 5 1.3 Cost of friction and wear 5 1.4 Summary 7 References 8 2 PHYSICAL PROPERTIES OF LUBRICANTS 11 2.1 Introduction 11 2.2 Oil viscosity 11 Dynamic viscosity 12 Kinematic viscosity 13 2.3 Viscosity temperature relationship 13 Viscosity-temperature equations 14 Viscosity-temperature chart 14 2.4 Viscosity index 15 2.5 Viscosity pressure relationship 16 2.6 Viscosity-shear rate relationship 22 Pseudoplastic behaviour 22 Thixotropic behaviour 24 2.7 Viscosity measurements 24 Capillary viscometers 24 Rotational viscometers 26 · Rotating cylinder viscometer 27 · Cone on plate viscometer 28 Other viscometers 29 2.8 Viscosity of mixtures 30 2.9 Oil viscosity classification 31 VIIIENGINEERING TRIBOLOGY SAE viscosity classification 31 ISO viscosity classification 33 2.10 Lubricant density and specific gravity 33 2.11 Thermal properties of lubricants 34 Specific heat 34 Thermal conductivity 35 Thermal diffusivity 35 2.12 Temperature characteristics of lubricants 35 Pour point and cloud point 36 Flash point and fire point 37 Volatility and evaporation 37 Oxidation stability 38 Thermal stability 39 Surface tension 40 Neutralization number 42 Carbon residue 43 2.13 Optical properties of lubricants 43 Refractive index 43 2.14 Additive compatibility and solubility 44 Additive compatibility 44 Additive solubility 44 2.15 Lubricant impurities and contaminants 44 Water content 44 Sulphur content 45 Ash content 45 Chlorine content 45 2.16 Solubility of gases in oils 45 2.17 Summary 48 References 48 3 LUBRICANTS AND THEIR COMPOSITION 51 3.1 Introduction 51 3.2 Mineral oils 52 Sources of mineral oils 52 Manufacture of mineral oils 54 Types of mineral oils 56 · Chemical forms 56 · Sulphur content 57 · Viscosity 57 CONTENTS IX 3.3 Synthetic oils 57 Manufacturing of synthetic oils 58 Hydrocarbon synthetic lubricants 60 · Polyalphaolefins 60 · Polyphenyl ethers 60 · Esters 60 · Cycloaliphatics 61 · Polyglycols 61 Silicon analogues of hydrocarbons 62 · Silicones 62 · Silahydrocarbons 62 Organohalogens 62 · Perfluoropolyethers 63 · Chlorofluorocarbons 63 · Chlorotrifluoroethylenes 63 · Perfluoropolyalkylethers 63 3.4 Emulsions and aqueous lubricants 65 Manufacturing of emulsions 65 Characteristics 65 Applications 66 3.5 Greases 66 Manufacturing of greases 66 Composition 67 · Base oils 67 · Thickener 67 · Additives 68 · Fillers 69 Lubrication mechanism of greases 69 Grease characteristics 72 · Consistency of greases 72 · Mechanical stability 73 · Drop point 74 · Oxidation stability 75 · Thermal stability 75 · Evaporation loss 76 · Grease viscosity characteristics 76 Classification of greases 78 Grease compatibility 80 Degradation of greases 80 X ENGINEERING TRIBOLOGY 3.6 Lubricant additives 81 Wear and friction improvers 82 · Adsorption or boundary additives 82 · Anti-wear additives 83 · Extreme pressure additives 85 Anti-oxidants 86 · Oil oxidation 86 · Oxidation inhibitors 88 Corrosion control additives 91 Contamination control additives 92 Viscosity improvers 93 Pour point depressants 95 Foam inhibitors 95 Interference between additives 95 3.7 Summary 96 References 97 4 HYDRODYNAMIC LUBRICATION 101 4.1 Introduction 101 4.2 Reynolds equation 101 Simplifying assumptions 103 Equilibrium of an element 103 Continuity of flow in a column 107 Simplifications to the Reynolds equation 109 · Unidirectional velocity approximation 109 · Steady film thickness approximation 109 · Isoviscous approximation 110 · Infinitely long bearing approximation 110 · Narrow bearing approximation 111 Bearing parameters predicted from Reynolds equation 113 · Pressure distribution 113 · Load capacity 113 · Friction force 114 · Coefficient of friction 115 · Lubricant flow 115 Summary 115 4.3 Pad bearings 116 Infinite linear pad bearing 116 · Bearing geometry 116 CONTENTS XI · Pressure distribution 117 · Load capacity 119 · Friction force 120 · Coefficient of friction 123 · Lubricant flow rate 124 Infinite Rayleigh step bearing 125 Other wedge geometries of infinite pad bearings 128 · Tapered land wedge 128 · Parabolic wedge 129 · Parallel surface bearings 130 · Spiral groove bearing 131 Finite pad bearings 132 Pivoted pad bearing 133 Inlet boundary conditions in pad bearing analysis 135 4.4 Converging-diverging wedges 137 Bearing geometry 138 Pressure distribution 138 · Full-Sommerfeld boundary condition 140 · Half-Sommerfeld boundary condition 141 · Reynolds boundary condition 143 Load capacity 144 4.5 Journal bearings 146 Evaluation of the main parameters 146 · Bearing geometry 146 · Pressure distribution 148 · Load capacity 149 · Friction force 154 · Coefficient of friction 155 · Lubricant flow rate 156 Practical and operational aspects of journal bearings 158 · Lubricant supply 159 · Cavitation 163 · Journal bearings with movable pads 164 · Journal bearings incorporating a Rayleigh step 164 · Oil whirl or lubricant caused vibration 165 · Rotating load 167 · Tilted shafts 169 · Partial bearings 170 · Elastic deformation of the bearing 171 XII ENGINEERING TRIBOLOGY · Infinitely long approximation in journal bearings 172 4.6 Thermal effects in bearings 172 Heat transfer mechanisms in bearings 173 · Conduction 174 · Convection 174 · Conducted/convected heat ratio 175 Isoviscous thermal analysis of bearings 176 · Iterative method 176 · Constant flow method 178 Non-isoviscous thermal analysis of bearings with locally varying viscosity 178 Multiple regression in bearing analysis 179 Bearing inlet temperature and thermal interaction between pads of a Michell bearing 181 4.7 Limits of hydrodynamic lubrication 182 4.8 Hydrodynamic lubrication with non-Newtonian fluids 184 Turbulence and hydrodynamic lubrication 184 Hydrodynamic lubrication with non-Newtonian lubricants 185 Inertial effects in hydrodynamics 186 Compressible fluids 187 Compressible hydrodynamic lubrication in gas bearings 189 4.9 Reynolds equation for squeeze films 191 Pressure distribution 192 Load capacity 193 Squeeze time 194 Cavitation and squeeze films 195 Microscopic squeeze film effects between rough sliding surfaces 196 4.10 Porous bearings 196 4.11 Summary 197 References 198 5 COMPUTATIONAL HYDRODYNAMICS 201 5.1 Introduction 201 5.2 Non-dimensionalization of the Reynolds equation 201 5.3 The Vogelpohl parameter 202 5.4 Finite difference equivalent of the Reynolds equation 204 Definition of solution domain and boundary conditions 206 Calculation of pressure field 207 Calculation of dimensionless friction force and friction coefficient 207 Numerical solution technique for Vogelpohl equation 210 CONTENTS XIII 5.5 Numerical analysis of hydrodynamic lubrication in idealized journal and partial arc bearings 210 Example of data from numerical analysis, the effect of shaft misalignment 211 5.6 Numerical analysis of hydrodynamic lubrication in a real bearing 216 5.6.1 Thermohydrodynamic lubrication 216 Governing equations and boundary conditions in thermohydrodynamic lubrication 217 · Governing equations in thermohydrodynamic lubrication for a one-dimensional bearing 218 · Thermohydrodynamic equations for the finite pad bearing 221 · Boundary conditions 222 Finite difference equations for thermohydrodynamic lubrication 223 Treatment of boundary conditions in thermohydrodynamic lubrication 226 Computer program for the analysis of an infinitely long pad bearing in the case of thermohydrodynamic lubrication 227 Example of the analysis of an infinitely long pad bearing in the case of thermohydrodynamic lubrication 228 5.6.2 Elastic deformations in a pad bearing 231 Computer program for the analysis of an elastically deforming onedimensional pivoted Michell pad bearing 233 Effect of elastic deformation of the pad on load capacity and film thickness 233 5.6.3 Cavitation and film reformation in grooved journal bearings 236 Computer program for the analysis of grooved 360° journal bearings 240 Example of the analysis of a grooved 360° journal bearing 240 5.6.4 Vibrational stability in journal bearings 246 Determination of stiffness and damping coefficients 246 Computer program for the analysis of vibrational stability in a partial arc journal bearing 251 Example of the analysis of vibrational stability in a partial arc journal bearing 251 5.7 Summary 254 References 254 6 HYDROSTATIC LUBRICATION 257 6.1 Introduction 257 6.2 Hydrostatic bearing analysis 258 Flat circular hydrostatic pad bearing 258 · Pressure distribution 258 · Lubricant flow 259 · Load capacity 259 · Friction torque 260 XIVENGINEERING TRIBOLOGY · Friction power loss 262 Non-flat circular hydrostatic pad bearings 262 · Pressure distribution 263 · Lubricant flow 264 · Load capacity 265 · Friction torque 265 · Friction power loss 265 6.3 Generalized approach to hydrostatic bearing analysis 266 Flat circular pad bearings 266 Flat square pad bearings 266 6.4 Optimization of hydrostatic bearing design 267 Minimization of power 267 · Low speed recessed bearings 269 · High speed recessed bearings 269 Control of lubricant film thickness and bearing stiffness 270 · Stiffness with constant flow method 271 · Stiffness with capillary restrictors 271 · Stiffness with an orifice 273 · Stiffness with pressure sensors 274 6.5 Aerostatic bearings 275 Pressure distribution 276 Gas flow 276 Load capacity 277 Friction torque 277 Power loss 278 6.6 Hybrid bearings 278 6.7 Stability of hydrostatic and aerostatic bearings 278 6.8 Summary 279 References 279 7 ELASTOHYDRODYNAMIC LUBRICATION 281 7.1 Introduction 281 7. 2 Contact stresses 282 Simplifying assumptions to Hertz's theory 282 Stress status in static contact 283 Stress status in lubricated rolling and sliding contacts 283 7.3 Contact between two elastic spherical or spheroidal bodies 284 Geometry of contacting elastic bodies 285 · Two elastic bodies with convex surfaces in contact 286 CONTENTS XV · Two elastic bodies with one convex and one flat surface in contact 287 · Two elastic bodies with one convex and one concave surface in contact 288 Contact area, pressure, maximum deflection and position of the maximum shear stress 289 · Contact between two spheres 289 · Contact between a sphere and a plane surface 292 · Contact between two parallel cylinders 294 · Contact between two crossed cylinders with equal diameters 297 · Elliptical contact between two elastic bodies, general case 299 Total deflection 304 7.4 Elastohydrodynamic lubricating films 305 Effects contributing to the generation of elastohydrodynamic films 306 · Hydrodynamic film formation 306 · Modification of film geometry by elastic deformation 306 · Transformation of lubricant viscosity and rheology under pressure 307 Approximate solution of Reynolds equation with simultaneous elastic deformation and viscosity rise 307 Pressure distribution in elastohydrodynamic films 311 Elastohydrodynamic film thickness formulae 312 Effects of the non-dimensional parameters on EHL contact pressures and film profiles 313 · Effect of the speed parameter 313 · Effect of the materials parameter 314 · Effect of load parameter 314 · Effect of ellipticity parameter 315 Lubrication regimes in EHL - film thickness formulae 316 · Isoviscous-rigid 317 · Piezoviscous-rigid 318 · Isoviscous-elastic 318 · Piezoviscous-elastic 318 Identification of the lubrication regime 319 Elastohydrodynamic film thickness measurements 319 7.5 Micro-elastohydrodynamic lubrication and mixed or partial EHL 322 Partial or mixed EHL 323 Micro-elastohydrodynamic lubrication 325 7.6 Surface temperature at the conjunction between contacting solids and its effect on EHL 327 Calculation of surface conjunction temperature 328 · Flash temperature in circular contacts 331 XVIENGINEERING TRIBOLOGY · Flash temperature in square contacts 331 · Flash temperature in line contacts 334 True flash temperature rise 335 Frictional temperature rise of lubricated contacts 339 Mechanism of heat transfer within the EHL film 341 Effect of surface films on conjunction temperatures 342 Measurements of surface temperature in the EHL contacts 342 7.7 Traction and EHL 343 A simplified analysis of traction in the EHL contact 346 Non-Newtonian lubricant rheology and EHL 348 EHL between meshing gear wheels 350 7.8 Summary 352 References 352 8 BOUNDARY AND EXTREME PRESSURE LUBRICATION 357 8.1 Introduction 357 8.2 Low temperature - low load lubrication mechanisms 359 8.3 Low temperature - high load lubrication mechanisms 360 Model of adsorption on sliding surfaces 361 · Physisorption 362 · Chemisorption 364 · Influence of the molecular structure of the lubricant on adsorption lubrication 365 · Influence of oxygen and water 369 · Dynamic nature of adsorption under sliding conditions 371 · Mixed lubrication and scuffing 372 · Metallurgical effects 379 · Interaction between surfactant and carrier fluid 380 8.4 High temperature - medium load lubrication mechanisms 381 Chain matching 381 Thick films of soapy or amorphous material 384 · Soap layers 384 · Amorphous layers 385 8.5 High temperature - high load lubrication mechanisms 388 Model of lubrication by sacrificial films 389 Additive reactivity and its effect on lubrication 390 Nascent metallic surfaces and accelerated film formation 393 Influence of oxygen and water on the lubrication mechanism by sacrificial films 395 CONTENTS XVII Mechanism of lubrication by milder E.P. Additives 398 Function of active elements other than sulphur 398 Lubrication with two active elements 399 Temperature distress 401 Speed limitations of sacrificial film mechanism 403 Tribo-emission from worn surfaces 403 8.6 Boundary and E.P. lubrication of non-metallic surfaces 404 8.7 Summary 404 References 405 9 SOLID LUBRICATION AND SURFACE TREATMENTS 411 9.1 Introduction 411 9.2 Lubrication by solids 411 9.2.1 Lubrication by lamellar solids 412 Friction and wear characteristics of lamellar solids 415 · Graphite and molybdenum disulphide 415 · Carbon-based materials other than graphite 419 · Minor solid lubricants 420 9.2.2 Reduction of friction by soft metallic films 421 Reduction of friction by metal oxides at high temperatures 422 9.2.3 Deposition methods of solid lubricants 422 Traditional methods of solid lubricant deposition 423 Modern methods of solid lubricant deposition 423 Solid lubricants as additives to oils and polymers 424 9.3 Wear resistant coatings and surface treatments 426 9.3.1 Techniques of producing wear resistant coatings 427 Coating techniques dependent on vacuum or gas at very low pressure 427 · Physical vapour deposition 427 · Chemical vapour deposition 430 · Physical-chemical vapour deposition 430 · Ion implantation 431 Coating processes requiring localized sources of intense heat 432 · Surface welding 432 · Thermal spraying 433 · Laser surface hardening and alloying 436 Coating processes based on deposition in the solid state 436 Miscellaneous coating processes 438 Application of coatings and surface treatments in wear and friction control 438 Characteristics of wear resistant coatings 439 XVIIIENGINEERING TRIBOLOGY 9.4 Summary 442 References 442 10 FUNDAMENTALS OF CONTACT BETWEEN SOLIDS 447 10.1 Introduction 447 10.2 Surfaces of solids 447 Surfaces at a nano scale 448 Surface topography 449 Characterization of surface topography 452 · Characterization of surface topography by statistical parameters 452 Multi-scale characterization of surface topography 455 · Characterization of surface topography by Fourier transform 455 · Characterization of surface topography by wavelets 456 · Characterization of surface topography by fractals 457 Optimum surface roughness 460 10.3 Contact between solids 461 Model of contact between solids based on statistical parameters of rough surfaces 462 Model of contact between solids based on the fractal geometry of rough surfaces 465 Effect of sliding on contact between solid surfaces 467 10.4 Friction and wear 468 Onset of sliding and mechanism of stick-slip 469 Structural differences between static and sliding contacts 471 Friction and other contact phenomena in rolling 473 Concentration of frictional heat at the asperity contacts 476 Wear between surfaces of solids 477 10.5 Summary 478 References 478 11 ABRASIVE, EROSIVE AND CAVITATION WEAR 483 11.1 Introduction 483 11.2 Abrasive wear 483 Mechanisms of abrasive wear 484 Modes of abrasive wear 486 Analytical models of abrasive wear 487 Abrasivity of particles 494 Abrasive wear resistance of materials 499 · Abrasive wear resistance of steels 502 · Abrasive wear resistance of polymers and rubbers 504 CONTENTS XIX · Abrasive wear resistance of ceramics 505 Effect of temperature on abrasive wear 506 Effect of moisture on abrasive wear 507 Control of abrasive wear 507 11.3 Erosive wear 509 Mechanisms of erosive wear 509 Effect of impingement angle and impact speed on erosive wear rate 511 Effect of particle shape, hardness, size and flux rates on erosive wear rate 512 Erosive wear by liquid 513 Effect of temperature on erosive wear 515 Effect of erosion media on erosive wear 516 Erosive wear resistance of materials 518 · Erosive wear resistance of steels 520 · Erosive wear resistance of polymers 521 · Erosive wear of ceramics and cermets 523 11.4 Cavitation wear 524 Mechanism of cavitation wear 524 Cavitation wear resistance of materials 525 11.5 Summary 526 References 527 12 ADHESION AND ADHESIVE WEAR 533 12.1 Introduction 533 12.2 Mechanism of adhesion 533 Metal-metal adhesion 533 Metal-polymer adhesion 536 Metal-ceramic adhesion 537 Polymer-polymer and ceramic-ceramic adhesion 537 Effects of adhesion between wearing surfaces 538 · Friction due to adhesion 538 · Junction growth between contacting asperities as a cause of extreme friction 539 · Seizure and scuffing 542 · Asperity deformation and formation of wear particles 542 · Transfer films 544 12.3 Control of the adhesive wear 548 Contaminant layers formed due to surface oxidation and bulk impurities 549 Lubricants 549 Favourable combinations of sliding materials 550 XX ENGINEERING TRIBOLOGY 12.4 Summary 550 References 550 13 CORROSIVE AND OXIDATIVE WEAR 553 13.1 Introduction 553 13.2 Corrosive wear 553 Transition between corrosive and adhesive wear 557 Synergism between corrosive and abrasive wear 559 Tribochemical polishing 560 13.3 Oxidative wear 560 Kinetics of oxide film growth on metals at high and low temperatures 561 · Oxidative wear at high sliding speeds 562 · Oxidative wear at low sliding speeds 563 · Oxidative wear at high temperature and stress 564 · Oxidative wear at low temperature applications 565 · Transition between oxidative and adhesive wear 566 · Oxidative wear under lubricated conditions 566 Means of controlling corrosive and oxidative wear 567 13.4 Summary 567 References 568 14 FATIGUE WEAR 571 14.1 Introduction 571 14.2 Fatigue wear during sliding 572 Surface crack initiated fatigue wear 573 Subsurface crack initiated fatigue wear 575 Effect of lubrication on fatigue wear during sliding 577 Plastic ratchetting 578 14.3 Fatigue wear during rolling 579 Causes of contact fatigue 580 · Asperity contact during EHL and the role of debris in the lubricant in contact fatigue 580 · Material imperfections 581 Self-propagating nature of contact fatigue cracks 581 Subsurface and surface modes of contact fatigue 581 Effect of lubricant on contact fatigue 585 Hydraulic pressure crack propagation 585 Chemical effects of lubricant additives, oxygen and water on contact fatigue 586 Materials effect on contact fatigue 587 CONTENTS XXI Influence of operating conditions on rolling wear and contact fatigue 588 14.4 Means of controlling fatigue wear 589 14.5 Summary 589 References 590 15 FRETTING AND MINOR WEAR MECHANISMS 593 15.1 Introduction 593 15.2 Fretting wear 594 Microscopic movements within the contact under applied loads 594 · Elastic model for fretting contacts 594 · Elasto-plastic model for fretting contacts 596 Effect of amplitude and debris retention on fretting wear 597 Environmental effects on fretting wear 599 Effects of temperature and lubricants on fretting 602 Effect of materials properties and surface finish on fretting 604 Fretting fatigue 604 Practical examples of fretting 607 Means of controlling fretting 608 15.3 Melting wear 609 15.4 Wear due to electrical discharges 611 15.5 Diffusive wear 612 15.6 Impact wear 613 15.7 Summary 615 References 616 16 WEAR OF NON-METALLIC MATERIALS 619 16.1 Introduction 619 16.2 Tribology of polymers 619 Sliding wear of polymers, transfer layers on a harder counterface 621 Influence of counterface roughness, hardness and material type on transfer films and associated wear and friction of polymers 622 · Counterface hardness 623 · Counterface roughness 623 · Counterface surface energy 626 Influence of temperature on polymer wear and friction 626 · Limit on frictional temperature rise imposed by surface melting 627 · Effect of high frictional temperatures and sliding speeds on wear 630 · Combined effect of high surface roughness and elevated contact temperature on wear 631 Fatigue wear of polymers and long term wear kinetics 633 XXII ENGINEERING TRIBOLOGY Visco-elasticity and the rubbery state 634 Friction and wear in the rubbery state 635 · Schallamach waves 635 · Visco-elasticity and friction of rubbers 636 · Wear mechanisms particular to rubbery solids 637 Effect of lubricant, corrosive agents and microstructure on wear and friction of polymers 638 · Effects of lubricants 638 · Effects of corrosive agents 639 · Effect of oxidizing and biochemical reagents 640 · Effects of polymer microstructure 641 16.3 Tribology of polymer composites 643 Polymer blends 643 Fibre reinforced polymers 643 · Chopped fibre reinforced polymers 644 · Unidirectional and woven fibre reinforcements 644 · Modelling of wear of fibre reinforced polymers 646 Powder composites 647 16.4 Wear and friction of ceramics 648 Unlubricated wear and friction of ceramic-ceramic contacts 650 · Dry friction and wear of ceramics at room temperature 650 · Dry friction and wear of ceramics at elevated temperatures 652 · Friction and wear of ceramics in the presence of water or humid air 652 · Quantitative wear model of ceramics 653 · Dry wear and friction characteristics of individual ceramics 655 Lubricated wear and friction of ceramic-ceramic contacts 656 · Liquid lubrication 656 · Solid lubricants 658 Wear and friction of ceramics against metallic materials 659 Wear and friction of ceramics against polymers 662 Wear and friction of ceramic matrix composites 662 16.5 Summary 663 References 663 APPENDIX 669 Introduction 669 A.1 User friendly interface 669 A.2 Program ‘VISCOSITY 671 CONTENTS XXIII Program description 673 List of variables 674 A.3 Program ‘SIMPLE 674 Program description 676 List of variables 677 A.4 Program ‘PARTIAL 678 Program description 681 List of variables 684 A.5 Program ‘THERMAL 686 Program description 690 List of variables 693 A.6 Program ‘DEFLECTION 696 Program description 698 List of variables 701 A.7 Program ‘GROOVE 702 Program description 708 List of variables 714 A.8 Program ‘STABILITY 716 Program description 719 List of variables 721 INDEX 723
كلمة سر فك الضغط : books-world.net The Unzip Password : books-world.net أتمنى أن تستفيدوا منه وأن ينال إعجابكم رابط مباشر لتنزيل كتاب Engineering Tribology رابط من موقع عالم الكتب لتنزيل كتاب Engineering Tribology
|
|