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A Study on the Consolidation of Sulfide-Based Infrared Optical Ceramics by Yiyu Li a Thesis Submitted to the Faculty of Alfred U

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A Study on the Consolidation of Sulfide-Based Infrared Optical Ceramics by Yiyu Li a Thesis Submitted to the Faculty of Alfred U A STUDY ON THE CONSOLIDATION OF SULFIDE-BASED INFRARED OPTICAL CERAMICS BY YIYU LI A THESIS SUBMITTED TO THE FACULTY OF ALFRED UNIVERSITY IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN CERAMIC ENGINEERING ALFRED, NEW YORK DECEMBER, 2018 A STUDY ON THE CONSOLIDATION OF SULFIDE-BASED INFRARED OPTICAL CERAMICS BY YIYU LI B.S. CENTRAL SOUTH UNIVERSITY (2010) M.S. ALFRED UNIVERSITY (2015) SIGNATURE OF AUTHOR _____________________________________ APPROVED BY ______________________________________________ YIQUAN WU, ADVISOR _______________________________________________ S.K. SUNDARAM, ADVISORY COMMITTEE _______________________________________________ STEVEN C. TIDROW, ADVISORY COMMITTEE _______________________________________________ JUNJUN DING, ADVISORY COMMITTEE _______________________________________________ WILLIAM M. CARTY, CHAIR ORAL THESIS DEFENSE ACCEPTED BY _______________________________________________ ALASTAIR N. CORMACK, DEAN KAZUO INAMORI SCHOOL OF ENGINEERING ACCEPTED BY _______________________________________________ DR. W. RICHARD STEPHENS, JR PROVOST AND VP FOR ACADEMIC AFFAIRS ALFRED UNIVERSITY Alfred University theses are copyright protected and may be used for education or personal research only. Reproduction or distribution in part or whole is prohibited without written permission from the author. Signature page may be viewed at Scholes Library, New York State College of Ceramics, Alfred University, Alfred, New York. ACKNOWLEDGEMENTS Two roads diverged in a wood, and I— I took the one less traveled by, And that has made all the difference. — Robert Frost One’s life is usually created by making choices, so is mine. I am lucky to have made the choice to pursue my graduate studies in Ceramic Engineering at Alfred University I have benefited so much from so many people, who have so generously offered their precious help of various kinds. First, I would like to express my sincere gratitude to my adviser, Prof. Yiquan Wu, for his longstanding guidance, support and insightful suggestions during my graduate study and research. Over the past years he has not only taught me how to acquire those fundamentals of scientific research, but has also given a lot of opportunities for me to attend multiple sorts of academic conferences. His well-informed knowledge of science and technology, his great enthusiasm for research, and his industriousness and science rigorousness set me a very good example, which will be quite fairly valuable for my future life career. I am greatly indebted to my committee members, Prof. S.K. Sundaram, Prof. Steven Tidrow, and Prof. Junjun Ding, for their valuable and sagacious suggestions on my thesis work. From them I learned a lot on how to effectively perform a comprehensive study. Special gratitude goes to both Prof. Scott Misture and Prof. William Carty, for their instructions on characterization and ceramic processing, when I was a teaching assistant in their classes. Thanks are due to Swavek Zdzieszynski, Gerald Wynick, Francis Williams, and James Thiebaud, for their patience and technical guidance on how to make best use of the instruments at Alfred University. Thanks to Prof. Ivar Reimanis, Michael Knight, Prof. Do Kyung Kim, Dr. Wook Ki Jung, Dr. Jiang Li, Dr. Chaoyu Li, Dr. Jian Zhang, Dr. Peng Liu, Hao Lu, Prof. Sergey Mirov, Dr. Vladimir Fedorov, Dr. Lihua Zhang and Dr. Kim Kisslinger, for their timely help on off-campus pressure-assisted sintering experiments and characterizations. I gratefully acknowledge the Office of Naval Research (Grant N00014- 16-1-2404) for funding this research work under the guidance of Program Director Dr. Antti Makinen. I should also thank my friends and colleagues, Dr. Yin Liu, Yan Yang, Dr. Wei Zhang, Dr. Yuxuan Gong, Dr. Peng Gao, Dr. Jie Yin, Dr. Xianqiang Chen, Dr. Wenxia Tan, Guangran Zhang, Iva Milisavljevic, Chao Liu, Dr. Shengquan Yu, Dr. Liaoyuan Wang, Thomas Olson, Dr. Dimple Pradhan, Sarah Whipkey, Sean Locker, Dr. Peter Metz, Trevyn Hey, Hyojin Lee, Max Modugno, Alec Ladonis, and Michael Alberga for their friendship and help on my research. Thanks are due to Laura Grove, Samantha Dannick, and Pat LaCourse as well, for the help in reviewing format and references of my thesis. Last but not the least, I am so thankful to my dear wife, Dr. Yiming Li, who has rendered me constant love, care, encouragements, and considerateness. I am also grateful to my parents, my parents-in-law, and my grandparents, for their support, understanding, encouragement and love. This thesis is dedicated to them. All these people have helped making my life so rich and different. I will remember them for good, so long as I can breathe or my life lasts. Thank you all! iii TABLE OF CONTENTS Page Acknowledgements .................................................................................................. iii Table of Contents ..................................................................................................... iv List of Tables ............................................................................................................ vi List of Figures ......................................................................................................... vii Abstract .................................................................................................................. xiv I. INTRODUCTION ................................................................................................... 1 A. Infrared Optical Ceramics .................................................................................... 1 1. Background on Infrared Optical Ceramics ...................................................... 1 2. Research and Development of Infrared Optical Ceramics .............................. 3 B. Sulfide-Based Infrared Optical Ceramics ........................................................... 15 1. ZnS Infrared Optical Ceramics ...................................................................... 15 2. CaLa2S4 Infrared Optical Ceramics ............................................................... 29 3. Sulfide-Based Composite Infrared Optical Ceramics .................................... 38 C. Goals and Organization of the Thesis ................................................................ 41 II. PHASE TRANSITION BETWEEN SPHALERITE AND WURTZITE IN ZnS OPTICAL CERAMIC MATERIALS ............................ 44 A. Introduction ........................................................................................................ 44 B. Experimental Procedures .................................................................................... 46 C. Results and Discussion ....................................................................................... 48 D. Conclusions ........................................................................................................ 66 III. HOT-PRESSED Cr2+ DOPED ZnS INFRARED TRANSPARENT CERAMICS ........................................................................................................... 68 A. Introduction ........................................................................................................ 68 B. Experimental Procedures .................................................................................... 70 C. Results and Discussion ....................................................................................... 71 D. Conclusions ........................................................................................................ 77 iv IV. SYNTHESIS AND CHARACTERIZATION OF CaLa2S4 NANOPOWDER ................................................................................................... 79 A. Introduction ........................................................................................................ 79 B. Experimental Procedures .................................................................................... 80 C. Results and Discussion ....................................................................................... 85 1. Synthesis with High-Temperature Sulfurization ........................................... 85 2. Synthesis without High-Temperature Sulfurization ...................................... 90 D. Conclusions ...................................................................................................... 103 V. CONSOLIDATION OF CaLa2S4 INFRARED OPTICAL CERAMICS ......................................................................................................... 105 A. Introduction ...................................................................................................... 105 B. Experimental Procedures .................................................................................. 107 C. Results and Discussion ..................................................................................... 109 D. Conclusions ...................................................................................................... 125 VI. PRESSURE-ASSISTED CONSOLIDATION OF ZnS-CaLa2S4 COMPOSITE CERAMICS ................................................................................ 126 A. Introduction ...................................................................................................... 126 B. Experimental Procedures .................................................................................. 127 C. Results and Discussion ..................................................................................... 129 D. Conclusions .....................................................................................................
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