Preparation of Zirconia-Alumina Fine Powders by Hydrothermal Oxidation of Zr-A1 Alloys
Fine powders of pure metal oxides can be prepared by hydrothermal oxidation method. This technique can provide the fine powders of homogeneous ZrO2-Al2O 3 mixtures from Zr-Al alloys at temperatures 600-700 °C under 100 MPa pressure for 3 h, according to the reactions,
2 ZrAl3 + 13 H2O = 3 A12O3 + 2 ZrO2 + 13 H2, and
2 Zr5Al3 + 29 H2O = 10 ZrO2 + 3 Al2O3 + 29 H2.
The average crystallite sizes were 27–35 nm for a-Al2O3, 13–24 nm for nonoclinic ZrO2 and 9–12 nm for tetragonal ZrO2 in the products.
KeywordsAverage Crystallite Size Boron Carbide Alloy Oxidation Zirconium Hydride Hydrothermal Oxidation
Unable to display preview. Download preview PDF.
- 1.D. W. Johnson, Jr., Am. Ceram. Soc. Bull., 60 , 221–24, 243 (1981).Google Scholar
- 2.C. R. Veale, Fine Powders, Preparation, Properties and Uses, Halsted Press Div., Wiley & Sons, NY, 1972.Google Scholar
- 3.J. L. Pentecost, pp. 1–14 in Ceramic Fabrication Processes, edited by F. F. Y. Wang, Academic Press, NY, 1976.Google Scholar
- 4.M. Hoch, pp. 13–28 in Science of Ceramics, 9, edited by K. J. DeVries, Nederlandse Keramische Verenging, Noordwijkerhout, The Netherlands, 1977.Google Scholar
- 6.E. Tani, M. Yoshimura, and S. Somiya, J. Am. Ceram. Soc., 66 , in press (1983).Google Scholar
- 7.T. Shibuya, Yogyo Kyokai Shi, 90 , 603–609 (1982).Google Scholar
- 8.M. Yoshimura and S. Somiya, Am. Ceram. Soc. Bull., 59 , 246 (1980).Google Scholar
- 9.M. Yoshimura and S. Somiya, pp. 453–63 in Science and Technology of Zirconia, Advances in Ceramics, Vol. 3, edited by A. H. Heuer and L. W. Hobbs, The American Ceramics Society, Columbus, 1981.Google Scholar
- 10.M. Yoshimura and S. Somiya, in Proc. of 5th Int. Round Table Conf. on Sintering, Sept. 7–10, 1981, Portoroz, Yugoslavia, in press.Google Scholar
- 11.H. Toraya, M. Yoshimura, and S. Somiya, J. Am. Ceram. Cos., 65 , C-72 (1982).Google Scholar
- 12.H. Toraya, M. Yoshimura, and S. Somiya, J. Am. Ceram. Soc., 66 , in press (1983).Google Scholar
- 13.M. Yoshimura, S. Kikugawa, and S. Somiya, submitted to Funtaioyobi Funmatsu Yakin (J. Japan Soc. Powder Metallurgy).Google Scholar
- 14.P. E. D. Morgan, pp. 67–76 in Processing of Crystalline Ceramics, edited by H. Palmour III, R. F. Davis, and T. M. Hare, Plenum Press, NY, 1978.Google Scholar
- 16.C. Sheer, S. Korman, D. J. Angier, and R. P. Cahn, pp. 133–52 in Fine Particles, 2nd International Conference, edited by W. E. Kuhn, Electrochemical Society, Princeton, NJ, 1974.Google Scholar
- 17.M. Yoshimura and S. Somiya, pp. 23–26 in Proc. of the 4th Int.Conf. on Rapidly Quenched Metals, Vol. I, edited by T. Masumoto and K. Suzuki, Japan Institute of Metals, Sendai, 1982.Google Scholar
- 18.A. M. Alper, pp. 339 in Science of Ceramics, 3, edited by G. H. Steward, Academic Press Inc., London, 1967.Google Scholar
- 19.A. Krath and H. Meyer, Ber. Deut. Keram. Ges., UU, 61–72 (1965).Google Scholar