Porous YSZ ceramics by water-based gelcasting

Gelcasting, as a novel method to form ceramic bodies, has been successfully developed to fabricate porous YSZ ceramics with an open porosity of 33.1-5 0.3%, mean pore size of 0.66-0.98 mu m and the nitrogen permeability of 215 -438 m(3)/m(2).bar.h. In order to further illustrate the features of this w ater-based gelcasting process to prepare porous ceramics, the same YSZ powd ers were blended with the same additives, and then cold pressed and sintere d at the same conditions employed for gelcasting process. Compared with the cold pressed samples, the gelcast bodies exhibit higher open porosity, low er closed porosity, relatively larger pore size and thus higher gas permeab ility. Therefore, the developed gelcasting process is a very effective meth od to fabricate porous ceramics for filters or supports. (C) 1999 Elsevier Science Ltd and Techna S.r.l. All rights reserved.