Alumina gel-cast foams manufactured by using agarose as gelling agent were examined in terms of microstructural, mechanical and thermal properties. The microstructural SEM measurements of alumina foams were compared with X-ray micro tomography investigations also on the pore network. Young's modulus of alumina foams was determined by impulse excitation and ultrasonic sound velocity measurements. These two independent techniques showed similar results. Gibson and Ashby's model of completely open-cell and closed-cell foams was compared with experimental data from compression tests. The thermal conductivity measurements using laser-flash analysis were correlated with the pore network in the alumina foam structure.

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The influence of graphitization and composition of carbide-derived carbon (CDC) monoliths on the electrical and thermal conductivity was investigated. Carbon monoliths with varying porosities were synthesized employing biomorphous macroporous TiC and SiC as precursors. Graphitization was carried out in situ during high-temperature chlorination with and without addition of nickel, iron, and cobalt chloride to the carbide. The graphitized monoliths showed improved properties. The results demonstrate that despite graphitic carbon also glass-like carbon, stemming from the carbide synthesis, increases the thermal and electrical conductivity significantly.