Microstructure of Tubular Sic Ceramics Made from Bamboo-Charcoal
Hiromi NAKANO, Takayuki NAGASE, Takeshi SHIONO and Toshihiko NISHIDA
Abstract:Recently, SiC ceramic was synthesized from bamboo-charcoal and melted Si in an Ar atmosphere. The SiC formed around the inside pore of the bamboo-charcoal as a tubular ceramic. As a result, yield of the SiC ceramic reached about 30 %. The product heated for various time (0.1 h - 5 h) was analyzed by scanning- and transmission- electron microscopes with energy-dispersive spectroscopy. For 0.1 hour heating time, the product was composed of SiO2 as an amorphous state or SiC-SiO2 with complex structure. The SiO2 was formed easily because of residual oxygen in a furnace. The SiO2 was existed as a liquid phase at high temperature and accordingly the product shape was like a surface structure of bamboo-charcoal. Increasing the heating time, the SiO2 was reacted with C under Ar atmosphere and became SiC, and increased the SiC thickness < about 14 mm. The SiC ceramic possessed 3C structure, and the tendency to decrease by heating was seen as for the stacking disorders in interguranular. Key Words:Bamboo-charcoal, SiC, Transmission electron microscope, Microstructure, Biocast ceramics