Macroporous silicate ceramics prepared by freeze casting combined with polymer sponge method

A combined processing route using freeze casting and a polymer sponge has been introduced for preparing macroporous silicate materials with controlled “designer” pore structures. Water/ceramic slurry systems were used in this work. The typical processing characteristics resulting from freeze casting and the polymer sponge were carried through to the sintered microstructure. A reticulated structure consisted of the struts with highly interconnected, large open pores together the inner walls with fine dendritic pores were developed and both types of characteristic pores were aligned along the ice growth direction. The pore structure developed was relatively independent of the concentration of the starting slurry and the sintering temperature.