Biomorphous SiC-ceramics through gas-phase siliconizing

Wood exhibits a hierarchically built anatomy with a directed and at most open pore structure on the micro- and macrometer level. This open porous system makes wood an interesting raw material for conversion into ceramic materials by different infiltration reaction techniques. The present study was concentrated on the conversion of different kinds of wood into biocarbon templates following by conversion of biocarbon templates via different vapor phase infiltration methods (SiO-vapor, Si-vapor or H2/CH3SiCl3-gas mixture) into highly porous single phase, biomorphous SiC-ceramics. The mechanisms and kinetics of the silicon carbide formation during different vapor phase infiltration of porous biocarbon templates as well as the mechanical properties (bending and compression strength) were analyzed with respect of orientation, fractional density and strut microstructure in order to design the microstructure of the biomorphous silicon carbide ceramics.