The addition of participate carbon into oxide ceramics can significantly improve their durability and wear characteristics due to the lubricating properties of carbon. In the present work an alumina-carbon composite was prepared by pyrolytic cracking in inert atmosphere of the organic compounds added as lubricants, wetting agents and dispersants in the course of freeze granulation of an alumina powder. Carbon in the form of submicron-sized isometric graphitic inclusions was homogeneously distributed within the dense alumina matrix prepared by hot pressing. SiC was also formed by carbothermal reduction of the SiO_2-based sintering additive. The matrix consisted of submicron alumina grains. The Vickers hardness of the carbon-containing composites was higher than the hardness of their carbon-free counterparts (18 and 22 GPa respectively for carbon-free and carbon containing liquid phase sintered aluminas). The fracture toughness was not affected markedly by graphite incorporation.
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