SILICON CARBIDE FORMATION FROM NATURAL WOODS

Abstract

Processing of cellular ceramics with anisotropic pore structure by using silicon infiltration into carbonized template was investigated. Biomorphic silicon carbide (bioSiC) was produced by using two different types of natural woods which are Kapur and Dark Red Meranti. Carbon template was produced from a pyrolysis process followed by an infiltration process of melting silicon to produce bioSiC. The samples were dried in an oven in order to remove the moisture of the samples. The pyrolysis was done in two stages at a temperature of 500°C followed by 850°C. This study was to investigate the effect of infiltration temperature in the formation of SiC composites. Two different infiltration temperatures of 1500°C and 1600°C were used with constant holding time of 1 hour. The characteristic of the biomorphic silicon carbide was analyzed using the TGA, FESEM and EDX analysis. A wide variety of microstructures, densities and porosities were found depending on the type of wood used. Instead of carbon, it was found that both woods also reacted with nitrogen gas, which reduced the formation of SiC. The density of samples was increased as the working temperature increased.  Dark Red Meranti was found to be denser and exhibit higher porosity than Kapur due to the higher formation of SiC.