Alumina grain boundary migration

Figure 10.27 Reprinted from Farrer, J.K., Carter, C.B., and Ravishankar, N. (2006) The Effects of Crystallography on Grain Boundary Migration in Alumina J. Mater. Sci., 41(3), 661-674. Reproduced by permission of Springer.

Plot of grain boundary displacement versus anneal time for growth of a-plane sapphire seeds into 500 ppm Ti-doped and undoped aluminas at 1600°C. In comparison to results obtained previously with a lower purity powder, mobilities in undoped material are increased. However, the most striking feature is the increased migration rate for the Ti-doped material. 

Figure 24.22 Reprinted from Kaysser, W.A., Sprissler, M., Handworker, C.A., and Blendell, J.E. (1987) Effect of a liquid phase on the morphology of grain growth in alumina, J. Am. Ceram. Soc. 70 339. With permission from Blackwell Publishing and the American Ceramic Society. See also R. D. Monahan, R.D. and Halloran, J.W. (1979) Single-crystal boundary migration in hot-pressed aluminum oxide, J. Am. Ceram. Soc. 62, 564.

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