Chapter 1 Introduction: Tribology of Polymers 1.1 Macrotribology and Microtribology 1.2 Polymer Materials 1.2.1 Amorphous Polymers 1.2.2 Semi-crystalline Polymers 1.2.3 Surface Morphology 1.3 Polymer Wear in Orthopaedical Prostheses 1.4 Microscratching of Polymers 1.4.1 Principle of Microscratching 1.4.2 Characterisation of Microscratches 1.4.3 Debris Generation in Microscratching 1.4.4 Microscratching and Macroscopic Wear Rate 1.5 Aims of This Thesis Chapter 2 Materials and Experimental Techniques 2.1 Material Samples and Their Properties 2.2 Sample Preparation 2.3 Scanning Electron Microscope 2.3.1 Principles of SEM 2.3.2 Specifications of the Hitachi TM3000 SEM 2.3.3 Conductive Coating of Polymer Samples 2.4 Atomic Force Microscopy 2.4.1 Principles of AFM 2.4.2 NT MDT Atomic Force Microscope 2.5 Macroscopic Wear Testing 2.6 Summary Chapter 3 Development of Novel Microscratching Instrumentation 3.1 Scratching Tips 3.1.1 Conical Geometry 3.1.2 Cubic Corner Geometry 3.2 Microscratching Apparatus 3.2.1 Manual Microscratcher 3.2.2 Semi-automated Microscratcher 3.3 Summary Chapter 4 Microscratching of Polyethylene Terephthalate 4.1 Single-pass Unidirectional Microscratching 4.2 Microscratching with Directional Change 4.2.1 Single-pass Microscratching 4.2.2 Multiple-pass Microscratching 4.3 Summary Chapter 5 Microscratching of PMMA, PTFE, PEEK and UHMWPE 5.1 Experimental Details 5.2 Unidirectional Microscratching 5.3 Multiple-pass Microscratching with Directional Change 5.3.1 Bidirectional Microscratching 5.3.2 Square Pattern with 90° Directional Changes 5.3.3 Multi-pass Orthogonal Intersecting Microscratching 5.4 Scratch Deformation Mechanisms 5.5 Summary Chapter 6 Wear Debris Generation: Geometry Effects and Scaling 6.1 Macroscopic Visualization
6.1.1 Experimental Setup and Materials 6.1.2 Visualization of the Macroscopic Scratches 6.2 Microscratching Using a Conical Tip 6.2.1 Characterisation of the Unidirectional Microscratch 6.2.2 Bidirectional Conical Scratch 6.2.3 Square Conical Microscratching 6.2.4 Orthogonal Microscratching 6.3 Effect of the Attack Geometry of the Scratching Tip 6.4 Correlation of the Microtribology with Macroscopic Wear 6.4.1 Pin-on-disk Macroscopic Wear 6.4.2 Microscopic and Macroscopic Wear Rate 6.5 Summary Chapter 7 Microscratching Characterization of the Wear-in of UHMW Polyethylene in Prostheses 7.1 Rotating Platform Knee Prostheses 7.2 Aims of This Study 7.3 Experimental Details 7.3.1 Microscratching Depth Markers 7.3.2 Static Loading Experiments 7.3.3 Fitting the Microscratched Plugs 7.3.4 Wear Experiment 7.3.5 Radioisotope Tracing 7.4 Results and Discussion 7.4.1 Microscratches Before the Wear Experiment 7.4.2 Microscratches Under Static Load 7.4.3 Surface Characterisation After the Wear Experiment 7.5 Modelling the Wear Process 7.6 Summary Chapter 8 Conclusions and Outlook Bibliography
[