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High Temperature Volatility and Oxidation Measurements of Titanium and Silicon Containing Ceramic Materials QUYNHGIAO N. NGUYEN Cleveland State University – Chemistry Department National Aeronautics and Space Administration (NASA) HIGH TEMPERATURE VOLATILITY AND OXIDATION MEASUREMENTS OF TITANIUM AND SILICON CONTAINING CERAMIC MATERIALS QUYNHGIAO N. NGUYEN Bachelor of Science in Chemistry Notre Dame College May, 1996 Master of Science in Chemistry Cleveland State University August, 1998 submitted in partial fulfillment of requirement for the degree DOCTORAL OF PHILOSOPHY IN CLINICAL/BIOANALYTICAL CHEMISTRY at Cleveland State University May, 2008 This dissertation has been approved for the Department of Chemistry and the College of Graduate Studies by ___________________________________ Lily M. Ng, Ph.D. Dissertation Committee Chairperson Department/Date ___________________________________ James L. Smialek, Ph.D. Dissertation Research Advisor Department/Date ___________________________________ Kang N. Lee, Ph.D. Department/Date ___________________________________ John F. Turner II, Ph.D. Department/Date ___________________________________ Mary V. Zeller, Ph.D. Department/Date ACKNOWLEDGEMENTS Dissertation Advisor: Lily M. Ng, Ph.D. Cleveland State University and Research Advisor: James L. Smialek, Ph.D. National Aeronautics and Space Administration (NASA) Dissertation Committee Members also Cleveland State University – Chemistry Department Dereck F. Johnson, Elizabeth J. Opila and Nathan S. Jacobson NASA Glenn Research Center - Structures and Materials Division NASA Glenn Graduate Studies and the Independent Research and Development Programs Finally HOPE HIGH TEMPERATURE VOLATILITY AND OXIDATION MEASUREMENTS OF TITANIUM AND SILICON CONTAINING CERAMIC MATERIALS QUYNHGIAO N. NGUYEN ABSTRACT Titanium (Ti) containing materials are of high interest to the aerospace industry due to its high temperature capability, strength, and light weight. As with most metals an exterior oxide layer naturally exists in environments that contain oxygen (i.e. air). At high temperatures, water vapor plays a key role in the volatility of materials including oxide surfaces. This study first evaluates several hot-pressed Ti-containing compositions at high temperatures as a function of oxidation resistance. This study will also evaluate cold pressed titanium dioxide (TiO2) powder pellets at a temperature range of 1400°C - 1200°C in water containing environments to determine the volatile hydoxyl species using the transpiration method. The water content ranged from 0-76 mole % and the oxygen content range was 0-100 mole % during the 20-250 hour exposure times. Preliminary results indicate that oxygen is not a key contributor at these temperatures and the following reaction is the primary volatile equation at all three temperatures: TiO2 (s) + H2O (g) = TiO(OH)2 (g). iv TABLE OF CONTENTS Page ABSTRACT……………………………………………………. IV TABLE OF CONTENTS………………………………………. V LIST OF TABLES……………………………………………… VIII LIST OF FIGURES…………………………………………….. XI LIST OF EQUATIONS…………………………........................ XV CHAPTER I. INTRODUCTION………………………….. 1 1.1 Objectives…………………………………… 1 1.2 History of ceramics…………………………. 3 1.3 Aerospace requirements……………………. 5 1.4 Areas of interest……………………………. 5 1.5 Background and literature search…………… 6 1.6 Aim…………………………………………. 10 II. PRELIMINARY FINDINGS………………. 14 III. PROPOSED RESEARCH AND EXPERIMENT 16 3.1 Oxidation of Ti-containing composites……. 17 3.2 Modified horizontal furnace……………….. 25 3.2.1 Experimental set-up……………. 26 v 3.2.2 Analytical lab analysis………….. 27 3.2.3 Preliminary results ……………… 28 IV. TRANSPIRATION METHOD……………... 32 4.1 Experimental set-up………………………… 35 4.2 Materials……………………………………. 37 4.3 Furnace set-up………………………………. 38 4.4 Transpiration cell set-up……………………. 46 4.5 Analytical lab analysis……………………… 46 4.6 Data calculations……………………………. 49 4.7 TiO2 Results and discussions……………….. 52 V. SUMMARY AND CONCLUSION………………… 79 REFERENCES…………………………………………….. 82 WORKS CONSULTED…………………………………… 85 ADDITIONAL ACKNOWLEDGEMENTS………………. 86 APPENDICES……………………………………………… 87 A. Typical results obtained from the analytical lab 88 B. Justification for eliminated data points……... 89 C. 95% confidence interval calculations for 1400°C 90 D. 95% confidence interval calculations for 1300°C 91 E. Independent Research & Development Program vi 2007 Annual Report………………………… 92 F. Independent Research & Development Program 2006 New Research Proposal………………. 94 G. Independent Research & Development Program 2005 Annual Report………………………… 97 H. Independent Research & Development Program 2005 Proposal Summary……………………. 99 I. Independent Research & Development Program 2004 Annual Report………………………… 102 J. Independent Research & Development Program 2003 New Research Proposal………………… 104 Curriculum Vitae………………………………………….. 107 vii LIST OF TABLES Table Page I. Gas flow calibration data from the Tylan RO-28 flowmeter……………………………………………… 42 II. Comprehensive Ti-O-H results at 1400°C that includes run numbers, temperatures, time, test gas flow rates, monitored room pressure display, analytically measured Ti deposits, calculated cell gas flow rates, calculated partial pressure of Ti-O-H and log of the partial pressures of Ti-O-H and test gases………………………………. 55 III. Comprehensive Ti-O-H results at 1300°C that includes run numbers, temperatures, time, test gas flow rates, monitored room pressure display, analytically measured Ti deposits, calculated cell gas flow rates, calculated partial pressure of Ti-O-H and log of the partial pressures of Ti-O-H and test gases……………………………… 60 IV. Comprehensive Ti-O-H results at 1200°C that includes run numbers, temperatures, time, test gas flow rates, monitored room pressure display, analytically measured viii Ti deposits, calculated cell gas flow rates, calculated partial pressure of Ti-O-H and log of the partial pressures of Ti-O-H and test gases……………………………… 64 V. Additional 1200°C comprehensive Ti-O-H results that includes run numbers, temperatures, time, test gas flow rates, monitored room pressure display, analytically measured Ti deposits, calculated cell gas flow rates, calculated partial pressure of Ti-O-H and log of the partial pressures of Ti-O-H and test gases……………. 66 VI. Calculated equilibrium constant (Keq) for 1400°C results that includes run numbers, temperatures, time, test gas flow rates, monitored room pressure display, analytically measured Ti deposits, calculated cell gas flow rates, calculated partial pressure of Ti-O-H and log of the partial pressures of Ti-O-H, the inverse of temperature and the calculated lnKeq………………………………………. 72 VII. Calculated equilibrium constant (Keq) for 1300°C results that includes run numbers, temperatures, time, test gas flow rates, monitored room pressure display, analytically measured Ti deposits, calculated cell gas flow rates, ix calculated partial pressure of Ti-O-H and log of the partial pressures of Ti-O-H, the inverse of temperature and the calculated lnKeq……………………………………….. 73 VIII. Calculated equilibrium constant (Keq) for 1200’s°C results that includes run numbers, temperatures, time, test gas flow rates, monitored room pressure display, analytically measured Ti deposits, calculated cell gas flow rates, calculated partial pressure of Ti-O-H and log of the partial pressures of Ti-O-H, the inverse of temperature and the calculated lnKeq…………………. 74 IX. Calculated equilibrium constant (Keq) for 1200°C results that includes run numbers, temperatures, time, test gas flow rates, monitored room pressure display, analytically measured Ti deposits, calculated cell gas flow rates, calculated partial pressure of Ti-O-H and log of the partial pressures of Ti-O-H, the inverse of temperature and the calculated lnKeq……………………………………….. 75 x LIST OF FIGURES Figure Page 1(a). Model illustration and parabolic curve of SiC reaction in an O2(g) containing environment........................... 9 1(b). Model illustration and paralinear curve of SiO2 reaction in a H2O(g) containing environment ……… 9 2. Representative SEM image of a plasma-sprayed EBC cross-section with three coating layers …………….. 12 3. Chart of diffusion coefficient in some common ceramics with respect to temperature………………. 19 4. The Ellingham diagram of free energies of formation 20 5. Phase Diagram System for SiO2-TiO2……………… 21 v 6. Box furnace oxidation results for 50 /o SiC-TiC at four temperatures for 100 hours……………………. 22 v 7. SEM images of 50 /o SiC-TiC in the HPBR at 1000°C for 60 hours…………………………………………. 23 v 8. SEM images of 50 /o SiC-TiC in the HPBR at 1330°C for 7.5 hours………………………………………… 24 9. Schematic of the modified horizontal furnace used to xi determine potential TiO2(s) interaction with H2O(g) at 1500°C Modified horizontal furnace…………….. 30 10(a). Photograph of fused quartz tube post-modified horizontal furnace exposure. The dotted lines indicate the position of the fused quartz ampoule (collection tube) during the test…………………….. 31 10(b). Close-up photograph of both the fused quartz furnace tube and ampoule…………………………………… 31 11. Model curve of the anticipated data from transpiration measurements……………………………………….. 34 12. Schematic of the transpiration furnace, transpiration cell and fused quartz collection tubes………………. 41 13. Gas flow calibration chart measured with a Tylan RO-28 flowmeter…………………………….. 42 14. Typical representative H2O flow calibration of the Rainin Dynamax® peristaltic pump………………... 43 15. Photograph of heating tape used to warm up the gas and water lines prior to the introduction into the furnace 44 16(a). Photograph
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