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Micro-Porous Ceramics Using directionally $MgAl_2O_4/MgO$ eutectic crystals  

Lee, Jong-Ho (Gwangju Research Center, Korea Institute of Industrial Technology)
Publication Information
Journal of the Korean Crystal Growth and Crystal Technology / v.15, no.6, 2005 , pp. 229-233 More about this Journal
Abstract
Novel process was tried to obtain micro-porous ceramic body containing continuous pore channel. $MgAl_2O_4/MgO$ eutectic fibers and rods have been grown successfully by the micro-pulling-down method, and the microstructures and optical characterizations of grown crystals were performed. $MgAl_2O_4/MgO$ eutectic fibers of $0.3{\sim}1mm$ in diameter and about 500 mm in length, and the rods having 5 mm in diameter with approximately 60 mm in length have been grown with the $6{\sim}120mm/hr$ of growth speed. The eutectic fibers showed homogeneous microstructure in which MgO fiber aligned to the growth direction in the $MgAl_2O_4$ (spinel) matrix. The grown crystals looked semitransparency under naked eyes. Optical and orientational characterizations were performed. The second phase of MgO (periclase) was easily removed by selective etching with hydrochloric acid, and then porous bodies were obtained.
Keywords
$MgAl_2O_4/MgO$ eutectic crystal; Rod; Micro-pulling-down method; Directional solidification; micro-porous body;
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