SiC reticulated porous ceramics by 3D printing, gelcasting and liquid drying

Silicon carbide reticulated porous ceramics with a regular shape were successfully prepared by combining three-dimensional (3D) printing, gelcasting and liquid drying. A 3D reticulated structured polyvinyl alcohol (PVA) mould was first fabricated by 3D printing, and then a slurry with a high-loading of SiC was gelcast into it. The PVA mould could be removed without any damage to form the gelled SiC structure by immersion in an aqueous solution, i.e. by liquid drying. After sintering, dense SiC ceramics with reticulated structure were obtained. Zeta potentials, rheological properties, and gelling behaviors of the slurry were studied together with liquid drying technology and characteristics of the ceramics. The present method shows good potential for fabricating porous and/or complex-shaped high-quality ceramics, and could also be applied in various kinds of advanced ceramics.