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by Siu Wing Hon. / On t.p. T"c", "2", "3", and "7-x" are subscripts following "superconducting" in the title. / Parallel title in Chinese characters. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves [79]-[80]). / Acknowledgement --- p.i / Abstract --- p.ii / Table of Content --- p.iii / Chapter Chapter 1 : --- Introduction / Chapter Chapter 2 : --- Growth of YBCO on Spinel / Chapter 2-1. --- Why Spinel --- p.2-1 / Chapter 2-2. --- Film Deposition Technique --- p.2-3 / Chapter 2-2.1 --- Magnetron Sputtering Technique --- p.2-3 / Chapter 2-2.2 --- Pulsed Laser Ablation --- p.2-4 / Chapter Chapter 3 : --- Composition Analysis by XRF / Chapter 3-1. --- Introduction --- p.3-1 / Chapter 3-2. --- Minimum Penetration Depth of EDX for YBCO film --- p.3-5 / Chapter 3-3. --- Thin Film Method and Thin Film Limit --- p.3-9 / Chapter 3-4. --- XRF Setup --- p.3-14 / Chapter 3-5. --- Calibration --- p.3-14 / Chapter 3-5.1 --- Chemical method --- p.3-18 / Chapter 3-5.2 --- Absorption Factor --- p.3-18 / Chapter 3-5.3 --- Diffusion Rate --- p.3-22 / Chapter 3-5.4 --- Justification of Thin Film Method --- p.3-22 / Chapter 3-5.5 --- Result of Calibration by Chemical Method --- p.3-24 / Chapter 3-5.6 --- Calibration by Rutherford Backscattering --- p.3-28 / Chapter 3-6. --- Discussion on XRF --- p.3-31 / Chapter 3-6.1 --- Effect of diffraction line by substrate on X-ray spectrum --- p.3-31 / Chapter 3-6.2 --- Stability of X-ray power supply and its influence on spectrum --- p.3-34 / Chapter Chapter 4 : --- Structural Analysis and Rapid Thermal Annealing / Chapter 4-1. --- XRD Setup --- p.4-1 / Chapter 4-2. --- XRD Analysis --- p.4-2 / Chapter 4-2.1 --- θ-2θ Scan --- p.4-1 / Chapter 4-2.2 --- Phi Scan --- p.4-3 / Chapter 4-2.3 --- Study of Diffraction Peak --- p.4-9 / Chapter 4-3. --- RTA and its influence on structure --- p.4-11 / Chapter 4-3.1 --- RTA Setup --- p.4-13 / Chapter 4-3.2 --- Structural Improvement by RTA --- p.4-13 / Chapter Chapter 5 : --- Conclusion --- p.5-1 / Chapter Appendix : A. --- Mathematical Derivation of Thin Film Limit / Chapter B. --- Powder Diffraction Patterns of YBCO system / Reference

Ling Siu-hing. / Title also in Chinese characters. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 220-227). / ACKNOWLEDGEMENT --- p.i / ABSTRACT --- p.ii / Chapter Chapter 1 --- Ceramic thin film --- p.1 / Chapter 1. 1 --- """New stone era""---the importance of ceramics" --- p.1 / Chapter 1.2 --- The importance of epitaxial growth of YBCO films --- p.4 / Chapter 1.3 --- The importance of epitaxial growth of PZT films --- p.9 / Chapter 1.4 --- The similar structures of YBCO and PZT --- p.10 / Chapter Chapter 2 --- Epitaxy --- p.12 / Chapter 2. 1 --- Introduction --- p.12 / Chapter 2.2 --- Basic principle --- p.13 / Chapter Chapter 3 --- Sample preparation Techniques --- p.25 / Chapter 3.1 --- A glimpse at epitaxial film deposition --- p.25 / Chapter 3.2 --- Magnetron sputtering --- p.28 / Chapter 3.2.1 --- Principle --- p.28 / Chapter 3.2.2 --- Set-ups --- p.30 / Chapter 3.2.3 --- High pressure magnetron sputter gun --- p.33 / Chapter 3.2.4 --- Type II unbalanced magnetron gun modification --- p.42 / Chapter 3.3 --- Pulsed Laser Deposition (PLD) --- p.54 / Chapter 3.4 --- Rapid thermal annealing (RTA) --- p.62 / Chapter Chapter 4 --- Characterizations-principles and setups --- p.66 / Chapter 4.1 --- Structure-X-ray diffractometer --- p.66 / Chapter 4.1.1 --- Setup --- p.57 / Chapter 4.1.2 --- Characterization --- p.71 / Chapter 4.1.3 --- High temperature X-ray diffractometer (HTXRD) --- p.83 / Chapter 4.2 --- Surface morphology --- p.86 / Chapter 4.2.1 --- Scanning electron microscopy (SEM) --- p.86 / Chapter 4. 3 --- Composition --- p.89 / Chapter 4.3.1 --- Energy dispersive X-ray spectroscopy --- p.89 / Chapter 4.3.2 --- Rutherford backscattering spectrometry (RBS) --- p.91 / Chapter 4.4 --- Other characterization techniques --- p.93 / Chapter 4.4.1 --- Thickness measurement --- p.93 / Chapter 4.4.2 --- Measurement of Tc in YBCO --- p.93 / Chapter 4.4.3 --- Thermomechanical analysis system (TMS) --- p.95 / Chapter 4.4.4 --- Differential scanning calorimeter (DSC) --- p.98 / Chapter Chapter 5 --- Epitaxial films --- p.99 / Chapter 5. 1 --- YBCO films --- p.99 / Chapter 5.1.1 --- YBCO on sapphire --- p.99 / Chapter 5.1.2 --- YBCO on spinel (MgAl2O4) --- p.115 / Chapter 5.1.3 --- YBC0//SrTi〇3//spinel --- p.130 / Chapter 5.1.4. --- YBCO on Mg〇 --- p.134 / Chapter 5.1.5 --- YBCO on SrTi〇3(110) --- p.143 / Chapter 5.2 --- PZT films --- p.182 / Chapter 5.2.1 --- PZT on MgO --- p.182 / Chapter 5.2.2 --- PZT on spinel --- p.188 / Chapter 5.2.3 --- High temperature structural transition of PZT films --- p.195 / Chapter Chapter 6 --- Conclusion --- p.218 / REFERENCES --- p.220

by Yu-Kit Lam =鉍系超導體在各製備階段之機械及超導特性 / 林宇傑. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / by Yu-Kit Lam = Bi xi chao dao ti zai ge zhi bei jie duan zhi ji xie ji chao dao te xing / Lin Yujie. / Table of Contents --- p.i / Acknowledgments --- p.iv / Abstract --- p.v / Chapter Chapter 1 --- Related Work on Bulk Bi-based High Tc Superconductor --- p.1 / Chapter 1.1 --- Historical Background of Superconductivity --- p.1 / Chapter 1.2 --- Basic Properties of Superconductivity --- p.4 / Chapter 1.3 --- Basic Properties of Bi-based Superconductor --- p.7 / Chapter 1.4 --- Fabrication Methods of Bi-based Superconductor --- p.12 / Chapter 1.4.1 --- Precursor Preparation --- p.12 / Chapter 1.4.1.1 --- Solid State Reaction Method --- p.12 / Chapter 1.4.1.2 --- Sol-gel Method --- p.15 / Chapter 1.4.1.3 --- Co-decomposition Method --- p.17 / Chapter 1.4.1.4 --- Freeze-drying and Spray-drying Methods --- p.17 / Chapter 1.4.1.5 --- Comparison for precursor preparation methods --- p.18 / Chapter 1.4.2 --- Pelletization and Sintering --- p.20 / Chapter 1.5 --- Potential applications of Bi-based superconductors --- p.22 / Chapter 1.5.1 --- Criteria for practical applications --- p.22 / Chapter 1.5.2 --- Superconducting tapes --- p.23 / Chapter 1.5.3 --- Current leads --- p.26 / Chapter 1.6 --- Objectives of the Project --- p.27 / Chapter 1.7 --- References --- p.28 / Chapter Chapter 2 --- Fabrication of Bulk Bi(Pb)-2223 Superconductor --- p.33 / Chapter 2.1 --- Introduction --- p.33 / Chapter 2.2 --- Precursor Preparation --- p.33 / Chapter 2.3 --- Grinding Process --- p.34 / Chapter 2.4 --- Pelletization Process --- p.35 / Chapter 2.5 --- The Sintering --- p.37 / Chapter 2.6 --- Characterizations --- p.38 / Chapter 2.7 --- References --- p.40 / Chapter Chapter 3 --- Principles and Instruments of Characterizations --- p.41 / Chapter 3.1 --- Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy --- p.41 / Chapter 3.1.1 --- Basic Principle --- p.41 / Chapter 3.1.2 --- Sample Preparation --- p.42 / Chapter 3.2 --- Crystal Structure Determination Using X-ray Diffraction Spectroscopy --- p.44 / Chapter 3.3 --- Vibrating Sample Magnetometer --- p.48 / Chapter 3.3.1 --- Basic Principle --- p.48 / Chapter 3.3.2 --- Sample Preparation --- p.49 / Chapter 3.4 --- Standard Four-Probe Method for Electrical Measurement --- p.51 / Chapter 3.5 --- Density Measurement of Sintered Samples --- p.52 / Chapter 3.6 --- Hardness Tests --- p.54 / Chapter 3.7 --- Determination of Flexural Strength of Sintered Samples --- p.56 / Chapter 3.8 --- References --- p.57 / Chapter Chapter 4 --- Results and Discussions / Chapter 4.1 --- Results from X-Ray Diffraction Spectroscopy --- p.58 / Chapter 4.1.1 --- Green Pellet --- p.58 / Chapter 4.1.2 --- 50-Hour Sintered Pellet --- p.58 / Chapter 4.1.3 --- "100-Hour, 150-Hour, and 200-Hour Sintered Pellets" --- p.59 / Chapter 4.1.4 --- Volume Fraction of the High Tc Phase --- p.59 / Chapter 4.2 --- Microstructure Observed by Scanning Electron Microscopy --- p.63 / Chapter 4.2.1 --- Green Pellet --- p.63 / Chapter 4.2.2 --- 50-Hour Sintered Pellet --- p.64 / Chapter 4.2.3 --- "100-Hour, 150-Hour, and 200-Hour Sintered Pellets" --- p.64 / Chapter 4.3 --- Chemical Composition Using Energy Dispersive X-ray Spectroscopy --- p.68 / Chapter 4.4 --- Results from Vibrating Sample Magnetometer --- p.71 / Chapter 4.5 --- Densification of Sintered Samples --- p.75 / Chapter 4.6 --- Hardness at Various Stages of Processing --- p.77 / Chapter 4.7 --- Flexural Strength at Various Stages of Processing --- p.79 / Chapter 4.8 --- I-V Characterization Using Standard Four-Probe Method --- p.82 / Chapter 4.9 --- Weibull Modulii of Sintered Samples --- p.85 / Chapter 4.10 --- Future Oultlook --- p.86 / Chapter 4.11 --- References --- p.87 / Chapter Chapter 5 --- Summary --- p.89 / Appendix A Polishing of Pelletizing Mold / Chapter A.1 --- Introduction --- p.92 / Chapter A.2 --- Grinding Process --- p.92 / Chapter A.3 --- Final Polishing Process --- p.93

Aluminum-zirconium alloys exhibit superior strength at elevated temperature in comparison to traditional aluminum casting alloys. These alloys are heat-treatable and their strength depends to a large extent on the quenching and aging steps of the heat treatment process. However, measurements show that the critical cooling rate necessary to retain 0.6 wt. pct. zirconium(the minimum amount necessary for significant strengthening) in a super-saturated solid solution with aluminum is 90ºC/s, which is un-attainable with traditional casting processes. On the other hand, the critical cooling rate necessary to retain 0.4 wt. pct vanadium and 0.1 wt. pct. zirconium in a super- saturated solidsolution with aluminum is only 40ºC/s; which suggests that substituting vanadium for zirconium significantly decreases the critical cooling rate of the alloy. This is an important finding as it means that, unlike the Al-0.6Zr alloy, the Al-0.4V-0.1Zr alloy may be processed into useful components by traditional high pressure die-casting. Moreover, measurements show that the hardness of the Al-0.4V-0.1Zr alloy increases upon aging at 400ºC and does not degrade even after holding the alloy at 300ºC for 100 hours. Also, measurements of the tensile yield strength of the Al-0.4V-0.1Zr alloy at 300ºC show that it is about 3 times higher than that of pure aluminum. This increase in hardness and strength is attributed to precipitation of Al3(Zr,V) particles. Examination of these particles with high resolution transmission electron microscopy (HRTEM) and conventional TEM show that vanadium co-precipitates with zirconium and aluminum and forms spherical particles that have the L12 crystal structure. It also shows that the crystallographic misfit between the precipitate particles and the aluminum matrix is almost eliminated by introducing vanadium into the Al3Zr precipitate and thatthe mean radius of the Al3(Zr,V) particles is in the range from 1nm to 7nm depending on the alloy composition and aging practice. Finally, it is found that adding small amounts of silicon to the Al-0.4V-0.1Zr alloy effectively accelerates formation of the Al3(Zr,V) precipitate.

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Zhao Kun. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese. / Zhao Kun.