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| Introduction | |
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| Why is it called tribology? | |
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| Economic and technological importance of tribology | |
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| Some tribology success stories | |
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| Reducing automotive friction | |
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| MEMS and solving adhesion in Digital Micro-mirror Devices | |
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| Slider-disk interfaces in disk drives | |
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| A brief history of modern tribology | |
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| Scientific advances enabling nanoscale tribology | |
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| Breakthrough technologies relying on tribology at the small scale | |
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| Nanoimprinting | |
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| IBM's millipede for high density storage | |
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| Nanotechnology | |
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| References | |
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| Characterizing surface roughness | |
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| Types of surface roughness | |
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| Roughness parameters | |
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| Variations in Z-height | |
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| Asperity summits roughness parameters | |
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| Surface height distributions | |
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| Measuring surface roughness | |
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| Atomic force microscopy (AFM) | |
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| Example: Disk surfaces in disk drives | |
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| References | |
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| Mechanical properties of solids and real area of contact | |
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| Atomic origins of deformation | |
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| Elastic deformation | |
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| Basic relations | |
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| Elastic deformation of a single asperity | |
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| Approximating a single asperity contact | |
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| Elastic contact area for a sphere on a flat | |
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| Example: Spherical steel particle sandwiched between two flat surfaces | |
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| Plastic deformation | |
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| Basic relations | |
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| Hardness | |
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| Real area of contact | |
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| Greenwood and Williamson model | |
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| Example: TiN contacts | |
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| Real area of contact using the Greenwood and Williamson model | |
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| Example: Recording head on a laser textured disk surface | |
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| Inelastic impacts | |
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| References | |
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| Friction | |
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| Amontons' and Coulomb's laws of friction | |
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| Adhesion and plowing in friction | |
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| Adhesive friction | |
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| Plowing friction | |
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| Work hardening | |
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| Junction growth | |
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| Static friction | |
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| Stick-slip | |
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| Velocity-controlled stick-slip | |
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| Time-controlled stick-slip | |
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| Displacement-controlled stick-slip | |
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| References | |
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| Surface energy and capillary pressure | |
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| Liquid surface tension | |
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| Capillary pressure | |
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| Capillary pressure in confined places | |
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| The Kelvin equation and capillary condensation | |
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| Example: Capillary condensation of water in a nanosized pore | |
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| Example: Capillary condensation of an organic vapor at a sphere-on-flat geometry | |
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| Interfacial energy and work of adhesion | |
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| Surface Energy of Solids | |
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| Why solids are not like liquids | |
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| Experimental determination of a solid's surface energy | |
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| Contact angles | |
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| Estimating interfacial energies | |
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| Zisman method for estimating surface energy for a solid | |
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| Types of wetting | |
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| Contact angle measurements | |
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| Contact angle hysteresis | |
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| Adhesion hysteresis | |
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| References | |
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| Surface forces derived from surface energies | |
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| The Derjaguin approximation | |
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| Dry environment | |
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| Force between a sphere and a flat | |
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| Example: Adhesion force between two polystyrene spheres | |
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| Example: Adhesion force between a polystyrene sphere and a PTFE Flat | |
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| Example: Adhesion force for an atomically sharp asperity | |
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| Adhesion-induced deformation at a sphere-on-flat contact | |
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| The Johnson-Kendall-Roberts (JKR) theory | |
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| The Derjaguin-Muller-Toporov (DMT) theory | |
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| Adhesion deformation in nanoscale contacts | |
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| Wet environment | |
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| Force for a sphere-on-flat in a wet environment | |
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| Example: Lubricant meniscus force on an AFM tip | |
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| Solid-solid adhesion in the presence of a liquid meniscus | |
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| Water menisci in sand | |
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| Meniscus force for different wetting regimes at contacting interfaces | |
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| Toe dipping regime | |
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| Example: Toe dipping adhesion with exponential distribution of summit heights | |
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| Pillbox and flooded regimes | |
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| Immersed regime | |
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| Example: Liquid adhesion of a microfabricated cantilever beam | |
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| References | |
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| Physical origins of surface forces | |
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| Normal force sign convention | |
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| Repulsive atomic potentials | |
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| Van der Waals forces | |
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| Van der Waals forces between molecules | |
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| Retardation effects for dispersion forces | |
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| Van der Waals forces between macroscopic objects | |
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| Molecule-flat surface interaction | |
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| Flat-Flat interaction | |
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| Sphere-flat interaction | |
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| The Hamaker constant | |
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| Determining Hamaker constants from Lifshitz's theory | |
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| Example: Van der Waals force on a polystyrene sphere above a Teflon flat | |
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| Surface energies arising from van der Waals interactions | |
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| Van der Waals adhesive pressure | |
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| Van der Waals interaction between contacting rough surfaces | |
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| Example: Stuck microcantilevers | |
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| Example: Gecko adhesion | |
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| Van der Waals contribution to the disjoining pressure of a liquid film | |
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| Liquid-mediated forces between solids | |
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| Solvation forces | |
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| Example: Squalane between smooth mica surfaces | |
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| Oscillatory solvation forces at sharp AFM contacts | |
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| Forces in aqueous medium | |
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| Electrostatic double-layer force | |
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| Hydration repulsion and hydrophobic attraction | |
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| Contact electrification | |
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| Mechanisms of contact electrification | |
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| Conductor-conductor contact | |
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| Example: Recording head slider flying over a disk in a disk drive | |
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| Metal-insulator and insulator-insulator Contacts | |
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| AFM studies of contact electrification | |
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| References | |
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| Measuring surface forces | |
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| Surface force apparatus | |
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| Atomic force microscope | |
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| Examples of forces acting on AFM tips | |
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| Van der Waals forces under vacuum conditions | |
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| Capillary condensation of contaminants and water vapor | |
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| Bonded and unbonded perfluoropolyether polymer films | |
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| Electrostatic double-layer force | |
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| References | |
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| Lubrication | |
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| Lubrication regimes | |
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| Viscosity | |
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| Definition and units | |
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| Non-Newtonian behavior and shear degradation | |
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| Temperature dependence | |
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| Fluid film flow in confined geometries | |
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| Slippage at liquid-solid interfaces | |
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| Definition of slip length | |
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| Measuring slip at liquid-solid interfaces | |
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| Pressure drop versus flow rate method | |
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| Drainage versus viscous force | |
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| Mechanisms for slip at liquid-solid interfaces | |
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| Molecular slip | |
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| Molecular slip at low energy surfaces | |
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| Slippage of polymers melts | |
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| Apparent slip | |
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| Example: Shear stress in the presence of slip | |
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| Why does the no-slip boundary condition work so well? | |
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| Fluid film lubrication | |
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| Hydrodynamic lubrication | |
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| Inclined plane bearing | |
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| Rayleigh step bearing | |
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| Journal bearings | |
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| Gas bearings | |
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| Slip flow in gas bearings | |
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| Elastohydrodynamic lubrication | |
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| Pressure dependence of viscosity | |
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| Pressure-induced elastic deformation | |
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| Example: Minimum film thickness between sliding gear teeth | |
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| Experimental measurements of elastohydrodynamic lubrication | |
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| Important physical and chemical properties of lubricants | |
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| Surface tension | |
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| Thermal properties | |
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| References | |
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| Lubrication in tight spots | |
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| Confined liquids | |
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| Boundary lubrication | |
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| Molecular mechanisms of boundary lubrication | |
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| Molecularly thin liquid boundary lubricant layers | |
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| Example of the importance of end-groups in a liquid lubricant film | |
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| Capillary and disjoining pressures | |
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| Disjoining pressure | |
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| Distribution of a liquid film around a pore opening | |
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| Example: Measurement of the disjoining pressure of a perfluoropolyether lubricant | |
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| Lubricant distribution between contacting surfaces | |
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| Meniscus force | |
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| Example: Stiction of a recording head slider | |
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| Calculating meniscus force | |
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| Example: Calculation of stiction force of disk drive sliders in the pillbox regime | |
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| Padded or stiction-free slider | |
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| Liquid menisci at high speeds | |
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| References | |
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| Atomistic origins of friction | |
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| Simple models for adhesive friction | |
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| Atomistic models for static friction | |
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| Frenkel-Kontorova model | |
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| Experimental realizations of ultra-low friction in incommensurate sliding systems | |
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| Tomlinson model | |
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| Example: An AFM tip sliding across an NaCl crystal at ultra-low loads | |
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| Molecular dynamic simulations | |
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| Example: Cold welding | |
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| Why static friction occurs in real-life situations | |
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| Atomic origins of kinetic friction | |
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| Sliding isolated molecules and monolayers across surfaces | |
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| Quartz crystal microbalance | |
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| Example: Xe on Ag(111) | |
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| Movement of a liquid film on a surface with the blow-off technique | |
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| Example: Wind-driven flow of perfluoropolyether lubricants on silicon wafers | |
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| Pinning of an absorbed layer | |
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| References | |
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| Wear | |
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| Simple model for sliding wear | |
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| Major influences on wear rates | |
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| Wear maps | |
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| Mechanisms of wear | |
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| Wear from plastic deformation | |
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| Adhesive wear | |
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| Example: An atomic level simulation of adhesive wear | |
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| Abrasive wear | |
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| Oxidative wear | |
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| Metals | |
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| Carbon overcoats | |
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| Ceramics | |
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| Plasticity at the nanoscale | |
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| References | |
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| Index | |