Chapter 26. A New Process of Manufacturing α-Alumina
- John B. Wachtman Jr.
Published Online: 28 MAR 2008
Copyright © 1993 The American Ceramic Society
A Collection of Papers Presented at the 94th Annual Meeting and the 1992 Fall Meeting of the Materials & Equipment/Whitewares Manufacturing: Ceramic Engineering and Science Proceedings, Volume 14, Issue 1/2
How to Cite
Wu, B. and Zha, C. (1993) A New Process of Manufacturing α-Alumina, in A Collection of Papers Presented at the 94th Annual Meeting and the 1992 Fall Meeting of the Materials & Equipment/Whitewares Manufacturing: Ceramic Engineering and Science Proceedings, Volume 14, Issue 1/2 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470314050.ch26
- Published Online: 28 MAR 2008
- Published Print: 1 JAN 1993
Print ISBN: 9780470375235
Online ISBN: 9780470314050
- alpha alumina;
- multiphase reaction principle;
- optical microscope observation;
- hexagonal bipyramid
A special process of manufacturing a-alumina was successfully developed. The advantage of this process is that the a-alumina obtained is in transparent dispersed powdered single crystal form, and need not be ground into powder when used as abradant, so the manufacturing cost can be reduced to very low levels. The particle size of the a-alumina is almost the same and its crystals are dodecahedrons or hexagonal bipyramids, which have not been observed in artificial a-alumina before. It is surprising that the hardness of the new type of a-alumina is 2500-2900 kg/mm2, but the hardness of currently available alumina is only 1900-2500 kg/mm2 (Japan) and 1400-1500 kg/mm2 (Zhengzhou, China), according to our test The sample with particle sizes from 2 to 100 an has been successfully produced by the new process.