竹炭及SiC陶瓷材料的结构与性能研究

Two types of bamboo, i.e. Phyllostachys heterocycla, Bambusa arundinacea, were selected as the raw materials to produce charcoal and SiC ceramics. First, biological carbon preforms were derived from bamboo by pyrolysis under N2 atmosphere, and then used as templates for molten silicon infiltration at 1450℃ in an argon atmosphere to form SiC ceramics. The pyrolysis process was studied by TGA, SEM, energy dispersive analysis of Xrays and XRD was used to characterize the microstructure, phases and physicochemical structure changes during the wood toceramic conversion. The compressive mechanical behavior of the bambooderived SiC materials was measured by a universal testing machine. Results show that the carbon preforms and the final SiC ceramics both inherit the anisotropic microstructure of bamboo. The SiC ceramics prepared by this technique are multiphase solids composed of SiC, freesilicon and C. The SiC ceramic materials produced from these two bamboo species show differences in fracture, phasecomposition and compressive strength.