Abnormal Grain Growth Mechanism of Calcium Hexaluminate Phase

  • Song, Jun-Ho (Department of Ceramic Engineering, Kangnung National University,) ;
  • Jo, Young-Jin (Department of Ceramic Engineering, Kangnung National University,) ;
  • Bang, Hee-Gon (Department of Ceramic Engineering, Kangnung National University,) ;
  • Park, Sang-Yeup (Department of Ceramic Engineering, Kangnung National University,)
  • Published : 2006.09.24

Abstract

Calcium-hexaluminate phase $(CA_6)$ is known to be effective for the crack shielding due to the spinel block crystal structure. In this study, we focused to the control of $CA_6$ morphology for good damage tolerance behavior in alumina and zirconia/calcium-hexaluminate $(CA_6)$ composites. Calcium-hexaluminate $(CA_6)$ composites were prepared from zirconia, alumina and calcium carbornate powders. Calcium-hexaluminate $(CA_6)$ phase was obtained by the solid reaction through the formation of intermediate phase $(CA_2)$. $CA_6$ phase showed the column type abnormal grain grown behavior composed of small blocks. Due to the typical microstructure of $CA_6$, alumina and zirconia/calcium-hexaluminate composites provide a well controlled crack propagation behavior.

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