Description: 1. Introduction.- 1.1 Definition and History of Tribology.- 1.1.1 Definition.- 1.1.2 History.- 1.2 Industrial Significance of Tribology.- 1.3 Physics of Magnetic Recording.- 1.3.1 Basic Principle.- 1.3.2 Vertical Recording.- 1.3.3 Methods of Encoding Binary Information.- 1.3.4 Design Considerations.- Recording Density.- Reproduced Signal Amplitude.- Signal-to-Noise Ratio.- 1.4 Magnetic Data-Storage Systems.- 1.4.1 History of Magnetic Recording.- Storage Hierarchy.- 1.4.2 Examples of Modern Data-Storage Systems.- Tape Drives.- Floppy Disk (Diskette) Drives.- Rigid Disk Drives.- 1.4.3 Head Materials.- Permalloys.- Mu-Metal and Hy-Mu 800B.- Sendust Alloys.- Alfenol Alloys.- Amorphous Magnetic Alloys.- Ferrites.- Some Examples of Head Constructions.- 1.4.4 Media Materials.- Flexible Media.- Rigid Disks.- Functional Requirements.- 1.4.5 Manufacturing Processes of Magnetic Media.- Particulate Tapes.- Particulate Floppy Disks.- Rigid Disks.- References.- 2. Solid Surface Characterization.- 2.1 The Nature of Surfaces.- 2.2 Statistical Analysis of Surface Roughness.- 2.2.1 Average Roughness Parameters.- 2.2.2 Probability Distribution and Density Functions.- 2.2.3 Surface Height Distribution Function.- 2.2.4 Texture Descriptors.- 2.2.5 Distribution and Statistics of the Asperities and Valleys.- 2.2.6 Practical Considerations in Measurement of Roughness Parameters.- Long- and Short-Wavelength Filtering.- Measuring Length.- 2.3 Measurement of Surface Roughness.- 2.3.1 Mechanical Stylus Method.- Surface Mapping.- Measurement of Circular Surfaces.- Relocation.- Replication.- Sources of Errors.- 2.3.2 Optical Methods.- Taper-Sectioning Method.- Light-Sectioning Method.- Specular Reflection Methods.- Diffuse Reflection (Scattering) Methods.- Speckle Pattern.- Optical Interference Methods.- Digital Optical Profiler.- 2.3.3 Fluid Methods.- 2.3.4 Electrical Methods.- 2.3.5 Electron Microscopy Methods.- Reflection Electron Microscopy.- Integration of Backscattered Signal.- Stereomicroscopy.- 2.3.6 Scanning Tunneling Microscopy.- 2.3.7 Atomic Force Microscopy.- 2.3.8 Comparison of Measurement Methods.- 2.4 Measurement of Isolated Asperities.- 2.4.1 Optical Methods.- 2.4.2 Glide Test Methods.- 2.5 Physico-Chemical Characteristics of Surface Layers.- 2.5.1 Deformed Layer.- 2.5.2 Bielby Layer.- 2.5.3 Chemically-Reacted Layer.- 2.5.4 Physisorbed Layer.- 2.5.5 Chemisorbed Layer.- 2.5.6 Surface Tension, Surface Energy, and Wetting.- 2.5.7 Methods of Surface Characterization.- References.- 3. Contact between Solid Surfaces.- 3.1 Physical Properties of Polymers.- 3.1.1 Physical States of Polymers.- 3.1.2 Complex Modulus and Compliance.- 3.1.3 Creep and Relaxation Behavior.- 3.1.4 Temperature and Frequency Effects.- 3.2 Apparent and Real Area of Contact.- 3.3 Analysis of the Real Area of Contact.- 3.3.1 Elastic Contact.- 3.3.2 Limit of Elastic Deformation.- 3.3.3 Optimization of Mechanical Properties and Surface Roughness Parameters of Magnetic Media.- 3.3.4 Calculations of the Real Areas of Contact of Typical Particulate Magnetic Tapes.- Experimental Evidence of Elastic Contacts in Magnetic Tapes.- Changes in Contact Area Because of Tape-Surface Wear.- 3.3.5 Calculations of the Real Area of Contact of Typical Magnetic Rigid Disks.- Optimization of Relative Young''s Moduli of Thin-Film Composite Structure.- 3.4 Measurement of the Real Area of Contact.- 3.4.1 Review of Measurement Techniques.- Electrical-Contact Resistance.- Optical Techniques.- Ultrasonic Technique.- Neutrographic Technique.- Paints and Radioactive Traces.- 3.4.2 Comparison of Different Measurement Techniques.- Calculation for Overestimation of the Contact Area by Various Optical Techniques.- Feasibility of Phase-Contrast Microscopy.- Selection of Optimum Measurement Technique.- 3.4.3 Measurement of Typical Magnetic Tapes.- Test Apparatus and Procedure.- Results and Discussion.- References.- 4. Friction.- 4.1 Introduction.- 4.2 Need for Controlled Friction.- 4.3 Friction Theories.- 4.3.1 The Deformation (Hysteresis) Friction.- 4.3.2 The Adhesional Friction.- Real Area of Contact.- Adhesion Strength of Contacts.- Experimental Evidence of Tabor''s Classical Theory of Adhesion.- Chemical Effects in Adhesion.- Surface Free Energy Theory of Adhesion.- Grain Boundary Effects on Adhesion.- 4.3.3 Macroscopic Theory of Adhesion for Polymers in the Rubbery State.- 4.3.4 Sources of Stiction.- Meniscus/Viscous Effects.- Microcapillary-Evacuation Effect.- Changes in Surface Chemistry.- 4.3.5 Summary.- 4.4 Role of Physical Properties in Magnetic Tapes.- 4.4.1 Description of Reciprocating Friction Test Apparatus and Test Procedure.- Data Analysis.- 4.4.2 Description of Portable Reciprocating Friction Test Apparatus and Test Procedure.- 4.4.3 Effect of Temperature.- Tape-Drive Tests.- 4.4.4 Effect of Curing.- 4.4.5 Effect of Particle Loading.- 4.4.6 Effect of Magnetic-Particle Distribution.- 4.4.7 Effect of Surface Roughness.- 4.4.8 Effect of Humidity.- 4.4.9 Effect of Sliding Velocity.- 4.4.10 Friction Reduction by High-Frequency Oscillations.- 4.4.11 Summary.- 4.5 Role of Interlayer Pressure in Magnetic Tapes.- 4.5.1 Measurement of Creep Compliance and its Relationship to Friction.- Description of Creep Apparatus.- Test Procedure.- Results and Discussions.- Relationship between Creep Compliance and Friction.- 4.5.2 Friction of Tapes with and without Rough Backside.- 4.5.3 Effect of Tape Relaxation.- 4.5.4 Summary.- 4.6 Role of Chemical Properties in Magnetic Tapes.- 4.6.1 Polyurethane Chemistry.- 4.6.2 Thermomechanical Performance of Coatings.- 4.6.3 Chemical Changes of Coatings.- Experimental Procedure.- Results and Discussions.- 4.6.4 Effect of Binder Hydrolysis on the Drive Performance.- Measurement of Stiction.- 4.6.5 Summary.- 4.7 Role of Physical and Chemical Properties in Rigid Disks.- 4.7.1 Description of Various Techniques to Measure Friction/Stiction in Disk Drives.- 4.7.2 Effect of Disk and Head Slider Material Properties.- 4.7.3 Effect of Surface Roughness of Disk and Head Slider.- 4.7.4 Effect of Contact Start-Stops.- 4.7.5 Effect of Liquid Lubricant Film.- 4.7.6 Effect of Organic Adsorbants.- 4.7.7 Effect of Humidity and Temperature.- 4.7.8 Effect of Rest Period.- 4.7.9 Effect of Head Slider Area.- 4.7.10 Effect of Head Slider Load.- 4.7.11 Effect of Drive Acceleration/Velocity.- 4.7.12 Methods to Reduce Friction/Stiction.- 4.7.13 Summary.- References.- 5. Interface Temperature of Sliding Surfaces.- 5.1 Introduction.- 5.2 Thermal Analysis.- 5.2.1 Sliding of Equally Rough Surfaces (Low Stress).- Independent (Flash) Temperature Rise (?f) of an Asperity Contact.- Steady-State Interaction Temperature Rise (?i).- Partition of Heat.- Average Transient Temperature of an Interface.- 5.2.2 Sliding of a Rough Surface on a Smooth Surface (Low Stress).- Steady-State, Independent (Flash) Asperity-Contact Temperature Rise(?f).- Steady-State Interaction Temperature Rise (?i).- Partition of Heat.- Average Transient Temperature of an Interface.- 5.2.3 Transient Conditions.- 5.2.4 Temperature Variation Perpendicular to the Sliding Surface.- 5.2.5 Summary.- 5.3 Application of Analysis to Particulate Magnetic Media.- 5.3.1 Measurement of Thermophysical Properties of Heads and Medium Materials.- Magnetic-Head Materials.- Magnetic Medium Materials.- 5.3.2 Analytical Predictions for Particulate Magnetic Tapes.- Rough-Rough Surface Condition.- Rough-Smooth Surface Condition.- Magnetic Particle (with no Coating of Polymeric Binder) in Contact with the Head Surface.- Transient Conditions.- Temperature Variation Perpendicular to the Sliding Surface.- 5.3.3 Summary.- 5.4 Temperature Measurement of Particulate Magnetic Tapes.- 5.4.1 Tape Transport System.- 5.4.2 Infrared Measurement System.- Operating Equations for the Infrared Microscope.- Spot Size, Detector Response Time, and Temperature Error Interval of the Infrared Microscope.- AGA Thermovision 750.- 5.4.3 Determination of the Tape Radiative Properties.- 5.4.4 Friction Force Measurements.- 5.4.5 Temperature Measurements.- 5.4.6 Correlation of Predicted and Measured Asperity-Contact Temperatures.- 5.4.7 Summary.- References.- 6. Wear Mechanisms.- 6.1 Types of Wear Mechanics.- 6.1.1 Adhesive Wear.- 6.1.2 Abrasive Wear.- 6.1.3 Fatigue Wear.- Rolling Contact Fatigue.- Rolling/Sliding Contact Fatigue.- Sliding Contact Fatigue.- Static Fatigue.- 6.1.4 Impact Wear.- Erosion.- Percussion.- 6.1.5 Corrosive Wear.- 6.1.6 Electrical-Arc-Induced Wear.- 6.1.7 Fretting and Fretting Corrosion.- 6.2 Head Wear.- 6.2.1 Head Body Wear.- Wear Mechanisms of Tape Heads.- Rigid Disk Head Sliders.- Magnetically Dead Layer in Ferrites.- Friction Polymers.- 6.2.2 Thin-Film Read-Write Gap Wear.- 6.2.3 Effect of Head/Tape Properties and Operating Parameters on Tape-Head Wear.- Head Material Hardness.- Head Material Grain Size.- Magnetic Particles.- Tape-Surface Roughness.- Isolated Asperities on Tape Surface.- Multiple Passes.- Tape Tension.- Tape Stiffness.- Sliding Speed.- Humidity.- 6.3 Medium Wear.- 6.3.1 Tape Wear.- Effect of Number of File Passes.- Effect of PVC.- Effect of Environment.- Summary.- 6.3.2 Rigid Disk Wear.- Particulate Disks.- Thin-Film Disks.- 6.4 Head-Medium Wear Studies using Autoradiographic Techniques.- 6.4.1 Head-Tape Interface.- Details of the Tape Drive and Neutron Activation of Ferrite Heads.- Preparation of Radioactive-Ferrite Standards.- Exposures of Tapes on X-Ray Films.- Optical Densitometer Measurements of X-Ray Films.- Measurement of the Average Mass of Radioactive Material on Tape and Drive-Component Surfaces.- Results and Discussions.- 6.4.2 Head-Disk Interface.- 6.5 Head-Tape Wear Studies In-Situ SEM.- 6.5.1 Description of Miniwear Test Apparatus.- 6.5.2 Results and Discussions.- 6.5.3 Summary.- 6.6 Tape-Path Component Wear.- 6.6.1 Description of Accelerated Flange Wear and Friction Test Apparatuses.- 6.6.2 Wear and Friction Data Using Different Flange Materials.- 6.6.3 Wear Data using Different Magnetic Tapes.- 6.6.4 Correlation of A

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