Chapter 4. Reactant Compact and Product Microstructures for TiC, TiB2, and TiC/TiB2 from SPS Processing
- John B. Wachtman Jr.
Published Online: 26 MAR 2008
Copyright © 1990 The American Ceramic Society, Inc.
14th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 11, Issue 9/10
How to Cite
Rice, R. W. (1990) Reactant Compact and Product Microstructures for TiC, TiB2, and TiC/TiB2 from SPS Processing, in 14th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 11, Issue 9/10 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470313053.ch4
- Published Online: 26 MAR 2008
- Published Print: 1 JAN 1990
Print ISBN: 9780470374931
Online ISBN: 9780470313053
Microstructures of TiC, TiB2, and TiC/TiB2 mixtures produced by self-propagating synthesis (SPS) were examined. Porosity levels were determined mainly by other process parameters, e.g., whether the part was unconstrained, constrained, or hot-pressed during the reaction. Pore sizes were determined mainly by outgassing in the former two. Grain sizes were mainly a function of the composition, and secondarily of fine residual porosity between grains. Thus, TiB2 yielded larger grains for comparable densities than TiC because of higher reaction temperatures, while TiC/TiB2 mixtures had finer grain sizes due to mutual inhibition of grain growth. However, these SPS-produced grain sizes tend to be somewhat greater than those commonly achievable by conventional hot-pressing. Considerable evidence of molten Ti is seen in these SPS products, including internal extrusion of Ti filaments. Evidence of thermal etching is seen on grains of TiC/TiB2, and especially TiB2.