| Abstract | 第5-6页 |
| 摘要 | 第7-18页 |
| List of Symbols | 第18-19页 |
| 1 Introduction | 第19-44页 |
| 1.1 Chemical refinement of Al-based alloys | 第19-23页 |
| 1.1.1 Historical background | 第19-20页 |
| 1.1.2 Fundamentals of grain refinement | 第20-21页 |
| 1.1.3 Overview of commercial master alloys for Al-grain refinement | 第21-23页 |
| 1.2 Current condition in the production of Al-Ti-C refiners | 第23-27页 |
| 1.2.1 Motivation for development and optimization | 第23-25页 |
| 1.2.2 Difficulties related to the production | 第25-26页 |
| 1.2.3 State of the art | 第26-27页 |
| 1.3 Production of the TiC-containing composites and alloys by the SHS | 第27-35页 |
| 1.3.1 Basics of the SHS | 第27-28页 |
| 1.3.2 Effect of A1 additions on the formation of TiC by the SHS approach | 第28-31页 |
| 1.3.3 Evolution of TiC shape during the SHS in Al-Ti-C system | 第31-34页 |
| 1.3.4 Production of the Al-TiC MMCs by the SHS | 第34-35页 |
| 1.4 Development of theories on the mechanism of Al-grain refinement | 第35-40页 |
| 1.4.1 The nucleant paradigm | 第35-38页 |
| 1.4.2 The solute paradigm | 第38页 |
| 1.4.3 The "Ti transition zone" theory for Al-Ti-C master alloys | 第38-40页 |
| 1.5 The research purpose and content of the paper | 第40-44页 |
| 2 Materials and Methods | 第44-52页 |
| 2.1 Research sequence | 第44-45页 |
| 2.2 Starting materials and equipment | 第45-49页 |
| 2.2.1 Equipment used for the master alloy preparation and refinement tests | 第45-47页 |
| 2.2.2 Starting materials for the master alloy preparation and refinement tests | 第47-49页 |
| 2.3 Characterization methods | 第49-52页 |
| 2.3.1 Macrostructure:samples preparation and grain size measurement | 第49页 |
| 2.3.2 XRD analysis | 第49页 |
| 2.3.3 OM analysis | 第49-50页 |
| 2.3.4 SEM analysis and EDS | 第50页 |
| 2.3.5 EPMA analysis | 第50页 |
| 2.3.6 TEM analysis | 第50-52页 |
| 3 Key parameters of conventional SHS approach for Al-5Ti-0.2C production | 第52-71页 |
| 3.1 Experimental procedures | 第52-54页 |
| 3.1.1 Master alloy preparation and characterization | 第52-54页 |
| 3.1.2 Refinement tests | 第54页 |
| 3.2 A1 powder content and exposure duration | 第54-62页 |
| 3.2.1 Effect on the combustion reaction parameters | 第54-55页 |
| 3.2.2 Effect on Al-5Ti-0.2C microstructure and phase composition | 第55-59页 |
| 3.2.3 Effect on Al-5Ti-0.2C refinement performance | 第59-62页 |
| 3.3 Production temperature | 第62-66页 |
| 3.3.1 Effect on the combustion reaction parameters | 第62页 |
| 3.3.2 Effect on Al-5Ti-0.2C microstructure and phase composition | 第62-65页 |
| 3.3.3 Effect on Al-5Ti-0.2C refinement performance | 第65-66页 |
| 3.4 Discussion | 第66-69页 |
| 3.4.1 Effect of Al on the SHS of TiC | 第66-67页 |
| 3.4.2 Utilization of primary benefits from combustion reaction | 第67-69页 |
| 3.5 Summary | 第69-71页 |
| 4 Improved SHS-approach for Al-5Ti-0.2C production | 第71-100页 |
| 4.1 Thermodynamic basis for the improved SHS | 第71-76页 |
| 4.2 Experimental procedures | 第76-78页 |
| 4.2.1 Master alloy preparation and characterization | 第76-78页 |
| 4.2.2 Refinement tests | 第78页 |
| 4.3 Assessment of the proposed method | 第78-82页 |
| 4.3.1 Preparation of Al-5Ti-0.2C at 1250℃ | 第78-81页 |
| 4.3.2 Al-5Ti-0.2C performance when produced at 1050-1150℃ | 第81-82页 |
| 4.4 Optimization of improved SHS route at 1050℃ | 第82-92页 |
| 4.4.1 Effect of holding duration τ_1/τ_2 on the Al-5Ti-0.2C performance | 第82-83页 |
| 4.4.2 Effect of holding duration τ_1/τ_2 on the Al-5Ti-0.2C microstructure | 第83-87页 |
| 4.4.3 Refinement performance of Al-5Ti-0.2C produced at 1050℃ | 第87-92页 |
| 4.5 Comparison of Al-5Ti-0.2C produced via SHS_(conv.) and SHS_(impr) | 第92-98页 |
| 4.5.1 Thermochemistry of the SHS reaction | 第92-94页 |
| 4.5.2 The microstructure and refinement performance | 第94-98页 |
| 4.6 Summary | 第98-100页 |
| 5 The role of excess Ti on the growth and nucleating ability of TiC | 第100-123页 |
| 5.1 Experimental procedures | 第100-103页 |
| 5.1.1 Master alloy preparation and characterization | 第100-102页 |
| 5.1.2 Refinement tests | 第102-103页 |
| 5.2 Effect on TiC growth and its distribution within the alloy structure | 第103-107页 |
| 5.3 Effect on the refinement performance of TiC-bearing master alloys | 第107-110页 |
| 5.4 Microstructure analysis of CPA1 inoculated with TiC and solute Ti | 第110-115页 |
| 5.5 Identification of Ti-rich layer around TiC particles | 第115-122页 |
| 5.6 Summary | 第122-123页 |
| Conclusions and Outlook | 第123-126页 |
| Conclusions | 第123-125页 |
| Outlook | 第125-126页 |
| Abstract of Innovation Points | 第126-127页 |
| 创新点 | 第127-128页 |
| References | 第128-137页 |
| Published Academic Papers during PhD Period | 第137-139页 |
| Acknowledgement | 第139-140页 |
| About the Author | 第140-142页 |
