Biomorphic Cellular Ceramics

Biotemplating—a new concept for preparation of ceramic composite materials with biomorphic microstructures will be described. Biological carbon preforms (CB-templates) were derived from different wood structures by high-temperature pyrolysis at temperatures between 800 and 1800 °C and used as templates for infiltration with gaseous or liquid Si to form SiC- and SiSiC-ceramics. During high-temperature processing, the microstructural details of the bioorganic preforms were retained. Cellular ceramic composites with unidirectional porous morphologies and anisotrophic mechanical properties were obtained. The cellular composites show low density, but high specific strength and excellent high temperature stability.