Chapter 12. Sol-Gel Coating of Fiber Tows
- John B. Wachtman Jr
Published Online: 28 MAR 2008
Copyright © 1991 The American Ceramic Society, Inc.
Proceedings of the 15th Annual Conference on Composites and Advanced Ceramic Materials, Part 1 of 2: Ceramic Engineering and Science Proceedings, Volume 12, Issue 7/8
How to Cite
Hay, R. S. (1991) Sol-Gel Coating of Fiber Tows, in Proceedings of the 15th Annual Conference on Composites and Advanced Ceramic Materials, Part 1 of 2: Ceramic Engineering and Science Proceedings, Volume 12, Issue 7/8 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470313831.ch12
- Published Online: 28 MAR 2008
- Published Print: 1 JAN 1991
Print ISBN: 9780470375099
Online ISBN: 9780470313831
The filaments of alumina fiber tows were continuously coated with many different oxides by passing them upward through a water-based sol with hexane floating on top, and then through a heat-treatment furnace. The sol wets the alumina-hexane interface and hexane probably wets the sol-air interface, which causes displacement of excess sol between the filaments. Therefore there was little bridging of coating between filaments and the tows were not cemented together. The coatings were characterized by optical microscopy, SEM, and TEM. Coating thicknesses ranged from 0.005 to 0.1 m̈m per pass, and 0.5 to 2.5 m̈m thicknesses were observed when thirteen coatings were applied sequentially. The major flaws in the coatings appeared to be caused by peeling and subsequent overcoating on later passes; this could probably be controlled by using sols that gel with higher green strength.