SiSiC-ceramic composites from biocarbon powder

The reactive infiltration of carbonaceous materials derived from biological tissues with liquid Si (LSI-process) represents an interesting processing scheme for manufacturing of ceramic matrix composites (CMC). The LSI-processing of porous biocarbon preforms prepared from pressed powders results in nearly dense SiSiC- or SiSiC/C-materials. The microstructure and material properties of the final CMC's depend on the morphology of the biocarbon powders and preforms, e.g. density, specific surface area, pore size, wetting as well as reaction behaviour with the Si-melt. SiC-based ceramics were prepared by spontaneous Si-melt infiltration at 1600°C of different carbon powder preforms. As the biocarbon source, a waste carbon powder from the bio-fuel production was used. The phase distribution and interface morphology of the resulting biocarbon derived SiC-based ceramics were compared with SiSiC/C-materials prepared from conventionally available carbon powder materials (carbon black, graphite powder).