We have succeeded in developing a novel method for preparation of porous alumina using egg yolk both as consolidating and foaming agents. This strategy allows the control of porosity not only by the varied concentration of yolk but also by managing the foaming process. Slurries of alumina powders and yolk was prepared by stirring the mixture with an alumina-to-yolk ratio of  1.0  for 3 h and the resulting slip was poured into cylindrical shaped molds. The slurries show a slight shear thinning behavior for a lower range of shear rates, and it changed to shear thickening at higher shear rates. Their viscosities are in the range of 0.6 - 1.1 Pa.s at 1000 s^-1 shear rate, thus indicating that the slurries are pourable under shear. Subsequently, they were subjected to drying at 110, 150,  and 180 °C with the varied time of 8, 12, and 60 min for foaming and/or consolidation. Foaming process condition determined mean pore size and pore distribution. The dried green bodies of the samples were then burned to remove the pore creating agent at 600 ºC for 1 h accordingly, followed by sintering at 1550°C for 2 h. Pore size distribution measurement showed that macropores of the sintered alumina porous bodies increased with the increased time and temperature of the drying process and were found in the range 50 – 800 μm. SEM measurement also confirmed this observation. Less foamed samples show lower shrinkage but higher compressive strength. A shrinkage of as low as 7.8% was observed for the sample dried at 110ºC but it increased significantly to 29.3% when dried at 180ºC. The compressive strength of the 110ºC's sample was 5.72 MPa at 43.6% porosity and it decreased to 4.57 MPa at 50.4% porosity when foamed at 180ºC.  These results have opened a novel preparative way for porous ceramics especially alumina-based porous materials designed for biomedical applications.

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