Chapter 60. Sintering of Silica Gels at a Constant Rate of Heating

  1. John B. Wachtman Jr.
  1. B. F. Zhu and
  2. L. L. Hench

Published Online: 28 MAR 2008

DOI: 10.1002/9780470314500.ch60

Proceedings of the 18th Annual Conference on Composites and Advanced Ceramic Materials - A: Ceramic Engineering and Science Proceedings, Volume 15, Issue 4

Proceedings of the 18th Annual Conference on Composites and Advanced Ceramic Materials - A: Ceramic Engineering and Science Proceedings, Volume 15, Issue 4

How to Cite

Zhu, B. F. and Hench, L. L. (1994) Sintering of Silica Gels at a Constant Rate of Heating, in Proceedings of the 18th Annual Conference on Composites and Advanced Ceramic Materials - A: Ceramic Engineering and Science Proceedings, Volume 15, Issue 4 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470314500.ch60

Author Information

  1. University of Florida Advanced Materials Research Center Alachua, FL 32615

Publication History

  1. Published Online: 28 MAR 2008
  2. Published Print: 1 JAN 1994

ISBN Information

Print ISBN: 9780470375327

Online ISBN: 9780470314500

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Keywords:

  • silica gel;
  • dried gel;
  • isothermal;
  • nonisothermal;
  • rate-controlling

Summary

An alkoxide-derived amorphous silica gel is thermodynamically unstable due to its excess surface energy and free volume. Compared with the conventional isothermal method, the constant-rate-heating (CRH) technique is faster, and provides more details in studying the initial-stage of sintering for thermally unstable materials like a dried gel. The sinterability of porous silica gels was investigated using nonisothermal techniques and dilatometry. It was found that generally only one rate-controlling mechanism of sintering was predominant at a certain temperature region. Results from this CRH study are compared to the sintering kinetics predicted from a cylindrical model.