Chapter 32. Microstructure and Viscosity of Hot Pressed Silicon Oxycarbide Glasses

  1. John B. Wachtman Jr.
  1. Michael Hammond,
  2. Else Breval and
  3. Carlo G. Pantano

Published Online: 26 MAR 2008

DOI: 10.1002/9780470314234.ch32

Proceedings of the 17th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 14, Issue 9/10

Proceedings of the 17th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 14, Issue 9/10

How to Cite

Hammond, M., Breval, E. and Pantano, C. G. (1993) Microstructure and Viscosity of Hot Pressed Silicon Oxycarbide Glasses, in Proceedings of the 17th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 14, Issue 9/10 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470314234.ch32

Author Information

  1. Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pa 16802

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 1993

ISBN Information

Print ISBN: 9780470375273

Online ISBN: 9780470314234

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Keywords:

  • microstructure;
  • amorphous;
  • viscosity;
  • crystallization;
  • oxycarbide

Summary

The microstructural evolution of silicon oxycarbide glasses has been studied as a function of hot pressing temperature up to 1650°C. The silicon oxycarbide glasses were synthesized using a sol/gel process. Due to the metastable nature of the oxycarbide glass precursor, the temperature and pressure used to process these materials was expected to influence their final microstructure and properties. The materials were characterized by chemical analysis, x-ray diffraction, TEM and29Si MAS NMR. It was found that the hot pressed oxycarbide glasses contained 5–20nm SiC microcrystals homogeneously distributed within an amorphous matrix of silica, silicon oxycarbide, and carbon; i. e., a silicon oxycarbide glass-ceramic. The viscosity of the oxycarbide glass-ceramics was found to be approximately 10–103times greater than that of fused silica.