Shape forming of ceramics with controllable microstructure by drying-free colloidal casting

Abstract

A new drying-free colloidal casting method was developed for shape forming of ceramics with controllable microstructure. A polymerizable solvent such as furfuryl alcohol (FA) was employed to disperse ceramic particles to form a colloidal ceramic suspension with good fluidity. After casting, the solvent was polymerized into a polymer, resulting in solidification of the colloidal suspension. For the purpose of demonstrating this casting method, three types of ceramic powders (NiO/YSZ, Al₂O₃ and YSZ) were used to fabricate a NiO/YSZ ceramic tube, an Al₂O₃ ceramic part with a hexagonal screw nut shape, and a YSZ thin film. Our study shows that the microstructure (pore size and porosity) of ceramics can be readily tuned by adjusting the amount of FA, and the drying-free casting method offers better controllability over the shape forming of a wide variety of ceramic materials.