Biomorphic Hierarchical Porous SIC Prepared from Carbonized Broomcorn Millet

Biomorphic silicon carbide (bioSiC) with hierarchical porous structures was prepared by biotemplating technology from broomcorn millet. Broomcorn millet was firstly carbonized at 800 degrees C into carbon template and then converted into biomorphic porous SiC ceramics by liquid silicon infiltration at 1600 degrees C in an inert atmosphere. The carbonization process of broomcorn millet was investigated by thermogravimetric analysis. The microstructures and phase of carbon template and biomorphic SiC were analyzed by X-ray diffractometer (XRD) and scanning electron microscope (SEM), respectively. The results suggest that carbon template has a mass loss of about 82% compared to dried broomcorn millet and possesses an alveolate cellular structures. Resulted SiC is mainly composed of beta-SiC and principally replicates the alveolate cellular microstructure of carbon template.