臺灣博碩士論文加值系統

A systematic study has been conducted to understand the colloidal behaviors of alumina and zirconia in aqueous suspensions and their corresponding EPD processes. The suspension stability of Al2O3/H2O and ZrO2/H2O can be achieved via either electrostatic or electrosteric effects. A homogeneous deposit can be obtained, and the hydrolysis can be inhibited by polyelectrolyte addition during EPD process.
For constant-current EPD process, the deposition rate of charged particle decreases with increasing polyelectrolyte concentration, increases with increasing current density, and is independent of solid loading. A kinetic equation has been derived from Faraday’s law and compared reasonably with the deposition rate data. Microstructure of sintered deposit shows that the highest density can be achieved of ~98% T.D. for Al2O3 and ~99% T.D. for ZrO2 respectively.

TABLE OF CONTENTS

ABSTRACT………………………………………………………Ⅰ
TABLE OF CONTENTS……………………………………………Ⅱ
LIST OF TABLES……………………………………………………Ⅳ
LIST OF FIGURES…………………………………………………Ⅴ
CHAPTER

1. INTRODUCTION AND OBJECTIVE……………………1
1.1 A Brief Summary of Ceramic Processing…………………1
1.2 Purpose of the Study………………………………………2

2. BACKGROUND………………………………………………4
2.1 Introduction…………………………………………4
2.1.1 Principle of Electrophoretic Deposition
2.2 Application of EPD……………………………………………5
2.3 Suspension System for EPD…………………………………6

3. EXPERIMENTAL METHODS AND PROCEDURE………9
3.1 Raw Materials…………………………………………………9
3.2 Suspension Preparation…………………………………10
3.3 Suspension Stability Measurement……………………11
3.4 Adsorption Measurement of Polyelectrolyte…………11
3.5 Powder Characterization……………………………………13
3.6 Ni/YSZ Cermet Preparation…………………………………14
3.7 Electrophoretic Deposition Process………………15
3.8 Sintering and Microstructure Characterization………16

4. RESULTS AND DISCUSSION……………………………26
4.1 Colloidal Stability of Suspension………………………26
4.2.1 The Effect of pH Value
4.2.2 The Effect of Polyelectrolyte Addition
4.2 Electrophoretic Deposition Process……………………28
4.2.1 The Effect of pH Value
4.2.2 The Effect of Polyelectrolyte Addition
4.3 Kinetics of Electrophoretic Deposition………………31
4.3.1 Adsorption of Polyelectrolyte
4.3.2 Deposition Rate- Effect of Polyelectrolyte
Addition
4.3.3 Deposition Rate- Effect of Current Density
4.3.4 Deposition Rate- Effect of Solid Loading
4.3.5 Faraday’s Law
4.4 Characterization of Deposits………………………………43
4.4.1 Scanning Electron Microscopy Observation
4.5 Application of EPD to SOFC…………………………………46
4.5.1 Fabrication of Ni/YSZ Cermet
4.5.2 EPD of Zirconia Coating
4.5.3 Microstructure Characterization
5. CONCLUSIONS……………………………………………104
BIBLOGRAPHY…………………107

BIBLIOGRAPHY

CHAPTER 2
1. Omer O. Van der Biest and Luc J. Vandeperre, “Electrophoretic Deposition of Materials”, Annu. Rev. Mater. Sci., 29, 327-52, 1999.
2. Partho Sarkar and Patrick S. Nicholson, “Electrophoretic Deposition（EPD）: Mechanism, Kinetics, and Application to Ceramics,” J. Am. Ceram. Soc. 79, [8] 1987-2002（1996）.
3. Faramarz Hosseinbabaei, Babak Raissidehkordi, “Electrophoretic deposition of MgO thick films from an acetone suspension,” J. Eur. Ceram. Soc., 20,（2000）2165-2168.
4. B. Ferrari, R. Moreno, P. Sarkar, P. S. Nicholson, “Electrophoretic deposition of MgO thick films from organic suspensions,” J. Eur. Ceram. Soc., 20,（2000）99-106.
5. R. Moreno, B. Ferrari, “Effect of the slurry properties on the homogeneity of alumina deposits obtained by aqueous electrophoretic deposition,” Materials Research Bulletin 35（2000）887-897.
6. Begoña Ferrari, Juan Carlos Fariñas, and Rodrigo Moreno, “Determination and Control of Metallic Impurities in Alumina Deposits Obtained by Aqueous Electrophoretic Deposition,” J. Am. Ceram. Soc., 84 [4] 733-39（2001）.
7. Z. Wang, P. Xiao, J. Shemilt, “Fabrication of composite coating using a combination of electrochemical methods and reaction bonding process,” J. Eur. Ceram. Soc., 20,（2000）1469-1473.
8. B. Ferrari, R. Moreno, “The conductivity of aqueous Al2O3 slips for electrophoretic deposition,” Materials Letters 28（1996）353-355.
9. C. –Y. Chen, S. –Y. Chen and D. M. Liu, “Electrophoretic Deposition Forming of Porous Alumina Membranes,” Acta matter. 47 [9] pp. 2717- 2726, 1999.
10. B. Ferrari, R. Moreno, “Electrophoretic Deposition of Aqueous Alumina Slips,” J. Eur. Ceram. Soc., 17,（1997）549-556.
11. Friedrich Harbach, Hans Nienburg, “Homogeneous Functional Ceramic Components through Electrophoretic Deposition from Stable Colloidal Suspensions－Ⅱ. Beta-Alumina and Concepts for Industrial Production,” J. Eur. Ceram. Soc., 18,（1998）685-692.
12. Rajendra N. Basu, Clive A. Randall, and Merrilea J. Mayo, “Fabrication of Dense Zirconia Electrolyte Films for Tubular Solid Oxide Fuel Cells by Electrophoretic Deposition,” J. Am. Ceram. Soc., 84 [1] 33-40（2001）.
13. Tatsumi Ishihara, Kuninobu Shimose, Takanari Kudo, Hiroyasu Nishiguchi, Taner Akbay, and Yusaku Takita, “Preparation of Yttria-Stablized Zirconia Thin Films on Stronium-Doped LaMnO3 Cathode Substrates via Electrophoretic Deposition for Solid Oxide Fuel Cells,” J. Am. Ceram. Soc., 83 [8] 1921-27（2000）.
14. Tatsumi Ishihara, Keiji Sato, and Yusaku Takita, “Electrophoretic Deposition of Y2O3-Stablized ZrO2 Electrolyte Films in Solid Oxide Fuel Cells,” J. Am. Ceram. Soc., 79 [4] 913-19（1996）.
15. Tatsumi Ishihara, Keiji Sato, Yukako Mizuhara, and Yusaku Takita, “Preparation of Yttria-Stablized Zirconia Films for Solid Oxide Fuel Cells by Electrophoretic Deposition Method,” Chemistry Letters, pp. 943-946, 1992.
16. Benjamin D. Hatton and Yoshio Sakka, “Influence of Washing on Zirconia Powder for Electrophoretic Deposition,” J. Am. Ceram. Soc., 84 [3] 666-68（2001）.
17. Masaharu Nagai, Kimihiro, Takao Umegaki, and Yasuhisa Takuma, “Electrophoretic Deposition of Ferroelectric Barium Titanate Thick Films and Their Dielectric Properties,” J. Am. Ceram. Soc., 76 [1]253-55（1996）.
18. Soichiro Okamura, Takeyo Tsukamoto and Nobuyuki Koura, “Fabrication of Ferroelectric BaTiO3 Films by Electrophoretic Deposition,” Jpn. J. Appl. Phys., 32（1993）pp. 4182-4185.
19. Partho Sarkar, Xuening Haung, and Patrick S. Nicholson, “Structural Ceramic Microlaminates by Electrophoretic Deposition,” J. Am. Ceram. Soc., 84 [3] 2907-2909（1992）.
20. B. Ferrari, A. J. Sánchez-Herencia, R. Moreno, “Aqueous electrophoretic deposition of Al2O3/Y2O3 layered ceramics,” Materials Letters 35（1998）370-374.
21. B. Ferrari, A. J. Sánchez-Herencia, R. Moreno, “Electrophoretic Forming of Al2O3/Y-TZP layered ceramics,” Materials Research Bulletin, 33, pp. 487-499, 1998.
22. Benjamin Hatton and Patrick S. Nicholson,, “Design and Fracture of Layered Al2O3/TZ3Y Composites Produced by Electrophoretic Deposition,” J. Am. Ceram. Soc., 84 [3] 571-76（2001）.
23. Rajenda N. Basu, Merrilea J. Mayo and Clive A. Randall, “Free Standing Sintered Ceramic Films from Electrophoretic Deposition,” Jpn. J. Appl. Phys., 38（1999）pp. 6462-6465.
24. Jau-Ho Jean, “Electrophoretic deposition of Al2O3-SiC composite,” Materials Chemstry and Physics 40（1995）285-290.
25. C. Zhao, L. Vandeperre, J. Vleugels, and O. Van Der Biest, “Cylindrical Al2O3/Y-TZPfunctionally graded materials by EPD,” British Ceramic Transactions 2000, 99 [6] pp. 284-87.
26. A. M. Affoune, B. L. V. Prasad, Hirohiko Sato, and Toshiaki Enoki, “Electrophoretic Deposition of Nanosized Diamond Particles,” Langmuir 2001, 17, 547-551.

27. Zhitomirsky, “Electrophoretic and Electrolytic Deposition of Ceramic Coating on Carbon Fibers,” J. Eur. Ceram. Soc., 18,（1998）849-856.
28. J. Van Tassel and C. A. Randall, “Electrophoretic Deposition and Sintering of Thin/Thick PZT Films,” J. Eur. Ceram. Soc., 19,（1999）955-958.
29. Sun-Li Huang, David Dew-Hughes, “Comprehensive investigation on microstructural and transport properties of electrophoretically deposited Bi2Sr2CaCu2O8＋δ/silver composite tapes with various heat treatment conditions,” Physica C 319（1999）104-126.
30. Partho Sarkar, Xuening Haung, and Patrick S. Nicholson, “Structural Ceramic Microlaminates by Electrophoretic Deposition,” J. Am. Ceram. Soc., 84 [3] 2907-2909（1992）.

CHAPTER3
1. J. Cesarano III, I. A. Aksay, "Stability of Aqueous α-Al2O3 Suspensions with Poly(methacrylic acid) Polyelectrolyte, " J. Am. Ceram. Soc., 71 [4] 250-255 (1988).

CHAPTER4
1. I. Zhitomirsky, A. Petric, “Electrophoretic deposition of ceramic materials for fuel cell applications,” J. Eur. Ceram. Soc., 20 (2000) 2055-61.
2. Y. Hirata, A. Nishimoto, and Y. Ishihara, “Forming of Alumina Powder by Electrophoretic Deposition,” J. Ceram. Soc. Jpn., Int. Ed., 99, 108-13 (1991).
3. H. C. Hamaker, “Formation of Deposition by Electrophoresis,” Trans. Faraday Soc., 36, 279-87 (1940).
4. Z. Zhang, Y. Huang, and Z. Jiang, “Electrophoretic Deposition Forming of SiC-TZP Composites in Nonaqueous Sol Media,” J. Am. Ceram. Soc., 77, 1946-49 (1994).
5. J. H. Jean and H. R. Wang, “Stabilization of Aqueous BaTiO3 suspensions with Ammonium Salt of Poly(acrylic acid) at various pH Values,” J. Mater. Res., 13, 2245-50 (1998).