Preparation of porous Al2O3-Ceramics by biotemplating of wood

A new approach for preparing of microcellular ceramic materials is the reproduction of wood morphologies by biotemplating, where the structural features of the native wood are maintained in the ceramic product. Biomorphic Al2O3-ceramics were manufactured via the sol-gel route by repeated infiltration of low viscous alumina sols into wood preforms and subsequently sintered in air at 1550degreesC. The microstructure and phase formation during processing were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), density and porosimetry measurements. In contrast to conventional processed, highly-porous Al2O3-ceramics, the microstructure of the biomorphic Al2O3-ceramics is characterized by an uniaxial pore morphology with pore diameters in the micrometer range, depending on the initially used wood template.