Chapter 24. Sintering of Amorphous Mullite with Crystalline Inclusions

  1. John B. Wachtman Jr
  1. De-Yin Jeng and
  2. Mohamed N. Rahaman

Published Online: 28 MAR 2008

DOI: 10.1002/9780470313831.ch24

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

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

Jeng, D.-Y. and Rahaman, M. N. (2008) Sintering of Amorphous Mullite with Crystalline Inclusions, 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.ch24

Author Information

  1. Ceramic Engineering Department University of Missouri-Rolla Rolla, MO 65401

Publication History

  1. Published Online: 28 MAR 2008
  2. Published Print: 1 JAN 1991

ISBN Information

Print ISBN: 9780470375099

Online ISBN: 9780470313831

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Keywords:

  • nucleation;
  • electronic;
  • polycrystalline;
  • microstructure;
  • stoichiometric

Summary

Highly sinterable amorphous mullite powder with the stoichiometric composition (3Al2O3·2SiO2) was synthesized by a sol-gel route and used as the matrix phase in the formation of particulate composites by conventional, pressureless sintering. The compacted mullite powder sintered to nearly theoretical density below ≈1200°C and the X-ray diffraction pattern of the fully crystallized powder was almost identical to that of stoichiometric mullite. The effect of rigid, crystalline mullite or ZrO2 inclusions on the sinterability of the synthesized mullite powder was investigated. Composites containing up to 22.5 vol% ZrO2 sintered to almost full density. However, the sintered density of the composites containing mullite inclusions decreased with either increasing volume fraction or decreasing size of the inclusions. While no reaction occurred between the ZrO2 inclusions and the matrix, X-ray data indicated that the mullite inclusions enhanced the independent nucleation and growth rate of the mullite crystals in the matrix.