Chapter 73. Titanium Effects on Sintering and Grain Boundary Mobility of Alumina

  1. J. P. Singh
  1. J. D. Powers and
  2. A. M. Glaeser

Published Online: 26 MAR 2008

DOI: 10.1002/9780470294444.ch73

Proceedings of the 21st Annual Conference on Composites, Advanced Ceramics, Materials, and Structures - B: Ceramic Engineering and Science Proceedings, Volume 18, Issue 4

Proceedings of the 21st Annual Conference on Composites, Advanced Ceramics, Materials, and Structures - B: Ceramic Engineering and Science Proceedings, Volume 18, Issue 4

How to Cite

Powers, J. D. and Glaeser, A. M. (1997) Titanium Effects on Sintering and Grain Boundary Mobility of Alumina, in Proceedings of the 21st Annual Conference on Composites, Advanced Ceramics, Materials, and Structures - B: Ceramic Engineering and Science Proceedings, Volume 18, Issue 4 (ed J. P. Singh), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470294444.ch73

Author Information

  1. Department Materials Science and Mineral Engineering, University of California, Berkeley, CA 94720–1760

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 1997

ISBN Information

Print ISBN: 9780470375532

Online ISBN: 9780470294444

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Keywords:

  • microstructure;
  • magnitude;
  • sintering;
  • mobility;
  • agglomerates

Summary

The effects of titanium additions on sintering, grain growth, and grain boundary migration in ultra-high-purity alumina have been studied. Titanium dopant, in amounts greater than a threshold value (between 0.05 cation% and 0.2 cation%) causes a dramatic enhancement in sintering rate in air at 1400°C. Sintering studies in vacuum indicate that microstructure development varies with the dopant valence: Ti4+ promotes facetted grain growth, while Ti3+ yields a more equiaxed microstructure. Titanium also increases grain boundary migration rates in alumina. Boundary mobility enhancements of nearly two orders of magnitude over previous results for undoped alumina have been observed.