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Laser Waterjet Heat Treatment on Super-Hard Materials Jingnan Zhao Iowa State University

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Laser Waterjet Heat Treatment on Super-Hard Materials Jingnan Zhao Iowa State University Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2016 Laser waterjet heat treatment on super-hard materials Jingnan Zhao Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Mechanical Engineering Commons Recommended Citation Zhao, Jingnan, "Laser waterjet heat treatment on super-hard materials" (2016). Graduate Theses and Dissertations. 15854. https://lib.dr.iastate.edu/etd/15854 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Laser waterjet heat treatment on super-hard materials by Jingnan Zhao A dissertation submitted to the graduate faculty in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Major: Mechanical Engineering Program of Study Committee: Pranav Shrotriya, Major Professor Reza Montazami Ganesh Balasubramanian Scott Chumbley Jarad Niemi Iowa State University Ames, Iowa 2016 Copyright ©Jingnan Zhao, 2016. All rights reserved. ii TABLE OF CONTENTS Page ACKNOWLEDGMENTS ......................................................................................... v ABSTRACT………………………………. .............................................................. vi CHAPTER I INTRODUCTION .......................................................................... 1 1.1 Introduce to super-hard materials ........................................................................ 1 1.2 Hardness measurement ........................................................................................ 3 1.3 Hybrid Laser waterjet heat (LWH) treatment technique ..................................... 5 1.4 Hardness change mechanism ............................................................................... 8 1.5 Dissertation Organization .................................................................................... 10 1.6 References ......................................................................................................... 11 CHAPTER II ULTRAHARD BORON NITRIDE MATERIAL THROUGH A HYBRID LASER/WATERJET BASED SURFACE TREATMENT ...................... 16 Abstract ......................................................................................................... 16 2.1 Introduction ......................................................................................................... 17 2.2 Experimental approach ........................................................................................ 19 2.2.1 Sintering of dual-phase materials ................................................................ 19 2.2.2 Laser waterjet heat (LWH) treatment experiment ...................................... 20 2.2.3 Measurement of micro-hardness ................................................................. 21 2.2.4 Microstructure and phase composition characterization............................. 21 2.3 Experiment results ............................................................................................... 22 2.3.1 As-sintered material .................................................................................... 22 2.3.2 LWH processing of BN material ................................................................ 24 2.3.3 Hardness measurements .............................................................................. 27 2.4 Raman spectroscopy and X-ray diffraction characterization ............................... 28 2.4.1 Surface grazing angle XRD analysis .......................................................... 28 2.4.2 Raman analysis ........................................................................................... 29 2.5 Discussion ......................................................................................................... 31 2.6 Conclusion ......................................................................................................... 36 2.7 References ......................................................................................................... 36 iii CHAPTER III ULTRAHARD POLYCRYSTALLINE CUBIC/WURTZITE BORON NITRIDE COMPOSITE THROUGH HYBRID LASER/WATERJET HEAT (LWH) TREATMENT .................................................................................. 40 Abstract ......................................................................................................... 40 3.1 Introduction ......................................................................................................... 41 3.2 Method ......................................................................................................... 46 3.3 Result ......................................................................................................... 50 3.4 Discussion ....................................................................................................... 53 3.5 Conclusion ...................................................................................................... 59 3.6 References ....................................................................................................... 60 CHAPTER IV HYBRID CO2 LASER WATERJET HEAT (LWH) TREATMENT OF BINDER BORON NITRIDE COMPOSITES WITH HARDNESS IMPROVEMENT ................................................................................ 65 Abstract ......................................................................................................... 65 4.1 Introduction ......................................................................................................... 65 4.2 Method ......................................................................................................... 69 4.3 Result ......................................................................................................... 73 4.4 Discussion and conclusion .............................................................................. 81 4.4.1 Microstructure of the sample before LWH treatment ................................. 83 4.4.2 Microstructure of the sample after LWH treatment .................................... 85 4.4.3 Hall-Petch effect verification ...................................................................... 90 4.4.4 Wear resistance study ................................................................................. 92 4.5 Conclusion ...................................................................................................... 94 4.6 References ....................................................................................................... 94 CHAPTER V HYBRID CO2 LASER WATERJET HEAT (LWH) TREATMENT OF BINDERLESS BORON NITRIDE COMPOSITES WITH HARDNESS IMPROVEMENT ..................................................................... 100 Abstract ......................................................................................................... 100 5.1 Introduction ......................................................................................................... 100 5.2 Method ......................................................................................................... 103 iv 5.3 Results and discussion .................................................................................... 108 5.3.1 LWH treated materials hardness measurements ......................................... 108 5.3.2 LWH treated materials toughness measurements ....................................... 110 5.3.3 Wear resistance study ................................................................................. 111 5.4 Conclusion ...................................................................................................... 112 5.5 References ....................................................................................................... 113 CHAPTER VI CONCLUSIONS AND FUTURE WORKS .................................. 115 6.1 Conclusions .......................................................................................................... 115 6.2 Future work .......................................................................................................... 116 v ACKNOWLEDGMENTS I would like to express my gratitude to everyone was involved in any of the projects that make this dissertation. I would like to thank my major professor, Dr. Pranav Shrotriya, for the opportunity to work with him. He has offered his support through his knowledge, expertise, and time. The success of my projects would not have been possible without his professional experience, patient guidance, and valuable inputs. I also would like to thank all my committee members: Dr. Scott Chumbley for teaching me in the courses I took with them that prepared me with the needed knowledge for my work in these projects; Dr. Ganesh Balasubramanian and Dr. Reza Montazami for their comments and valuable suggestions on these projects; Dr. Jarad Niemi for his help on my experiment design and statistic data analysis. Special thanks to all my collaborators for their support and contributions to this work. I greatly treasure the experience of working with Dr. Pal Molian. Also, I would like to thank all the fellow students I worked with or shared thoughts with: Ammar Melaibary, Zhuoru Wu, Wong Kwang Shiong, Zhichen Zhu, Agnivo Gosai, and Abdullah Alshehri. In addition, I
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