| 摘要 | 第9-11页 |
| Abstract | 第11-12页 |
| Chapter 1 Introduction | 第17-34页 |
| 1.1 Research background and significance | 第17页 |
| 1.2 Wheel materials | 第17-19页 |
| 1.2.1 Strengthening mechanism of ferrite-pearlite steel | 第17-18页 |
| 1.2.2 Wheel steels used on Chinese high-speed train | 第18-19页 |
| 1.3 Review of railway wheel damages | 第19-32页 |
| 1.3.1 Wear | 第19-22页 |
| 1.3.2 Mechanically induced RCF | 第22-29页 |
| 1.3.3 Thermally induced RCF | 第29-30页 |
| 1.3.4 Relationship between wear and RCF | 第30-32页 |
| 1.4 The contents of this dissertation | 第32页 |
| 1.5 Research object and plan | 第32-34页 |
| Chapter 2 Optimization of strength and toughness of railway wheel steel by alloy design | 第34-50页 |
| 2.1 Alloy design | 第35页 |
| 2.2 Experimental | 第35-37页 |
| 2.2.1 Materials | 第35-36页 |
| 2.2.2 Microstructural characterization | 第36页 |
| 2.2.3 Mechanical properties | 第36-37页 |
| 2.3 Results and discussions | 第37-48页 |
| 2.3.1 Microstructure | 第37-42页 |
| 2.3.2 Mechanical properties | 第42-48页 |
| 2.4 Conclusions | 第48-50页 |
| Chapter 3 Effect of different strengthening methods on rolling/sliding wear of ferrite-pearlite steel | 第50-68页 |
| 3.1 Materials and experiment | 第51-53页 |
| 3.1.1 Materials | 第51页 |
| 3.1.2 Experiment | 第51-53页 |
| 3.1.3 Observation of microstructures and hardness | 第53页 |
| 3.2 Results | 第53-61页 |
| 3.2.1 Microstructure and bulk hardness | 第53-56页 |
| 3.2.2 Wear behavior | 第56-57页 |
| 3.2.3 Subsurface microstructure | 第57-59页 |
| 3.2.4 Strain hardening behavior | 第59-61页 |
| 3.3 Discussions | 第61-67页 |
| 3.3.1 Strengthened mechanisms, microstructure and bulk hardness | 第61-64页 |
| 3.3.2 Worn surface hardness and wear resistance | 第64-66页 |
| 3.3.3 Strengthened mechanisms and worn surface hardness | 第66-67页 |
| 3.4 Conclusions | 第67-68页 |
| Chapter 4 Investigation on surface initiated and thermally induced RCF for HiSi wheel steel | 第68-89页 |
| 4.1 Materials | 第69页 |
| 4.2 WEL reproduction | 第69-77页 |
| 4.2.1 Test method | 第69-71页 |
| 4.2.2 Results and discussions | 第71-74页 |
| 4.2.3 Effect of materials on WEL formation | 第74-77页 |
| 4.3 RCF behaviors | 第77-84页 |
| 4.3.1 Test method | 第77页 |
| 4.3.2 Results | 第77-84页 |
| 4.4 Elastic-plastic analyses | 第84-85页 |
| 4.5 Results and discussions | 第85-88页 |
| 4.5.1 Crack initiation at WEL surface | 第85-87页 |
| 4.5.2 Crack propagation along the deformed material | 第87-88页 |
| 4.6 Conclusions | 第88-89页 |
| Chapter 5 Influence of laser dispersed treatment on resistance to wear and surface initiated rolling contact fatigue of railway wheel steel | 第89-101页 |
| 5.1 Experimental procedure | 第89-91页 |
| 5.1.1 Materials | 第89-90页 |
| 5.1.2 Wear tests | 第90页 |
| 5.1.3 RCF tests | 第90-91页 |
| 5.2 Results | 第91-99页 |
| 5.2.1 Microstructures and hardness | 第91-93页 |
| 5.2.2 Wear test result | 第93-96页 |
| 5.2.3 RCF test result | 第96-99页 |
| 5.3 Discussion | 第99-100页 |
| 5.3.1 Influence of LDT on wear resistance | 第99-100页 |
| 5.3.2 Influence of LDT on RCF resistance | 第100页 |
| 5.4 Conclusions | 第100-101页 |
| Chapter 6 Effect of micro-inclusion on RCF initiated at subsurface and deep defects forrailway wheel | 第101-119页 |
| 6.1 Evaluation method and experiment | 第102-104页 |
| 6.1.1 Method | 第102页 |
| 6.1.2 Experiment | 第102-104页 |
| 6.2 Results | 第104-109页 |
| 6.2.1 Microstructure and microhardness of pre-treated fatigue specimen | 第104-105页 |
| 6.2.2 Risk volume of fatigue specimen | 第105-106页 |
| 6.2.3 Inclusion sizes | 第106-109页 |
| 6.3 Discussions | 第109-113页 |
| 6.3.1 Effect of pre-treatment on fracture behaviors of fatigue specimen | 第109-110页 |
| 6.3.2 Effect of pre-treatment on the inclusion size | 第110-111页 |
| 6.3.3 Comparison of the inclusion sizes obtained by different methods | 第111页 |
| 6.3.4 Validation of the fatigue method | 第111-113页 |
| 6.4 Application | 第113-118页 |
| 6.4.1 Prediction of the maximum micro-inclusion size in full-scale wheel | 第113-114页 |
| 6.4.2 Effect of micro-inclusions on subsurface initiated RCF | 第114-118页 |
| 6.5 Conclusions | 第118-119页 |
| Conclusions | 第119-122页 |
| Acknowledgements | 第122-123页 |
| References | 第123-137页 |
| Publications and research results | 第137-138页 |
