Abstract:

Bamboo-based SiC ceramics were prepared by carbothermal reduction reaction between charcoal and silica that was introduced into bamboo through a sol-gel and vacuum/pressure infiltration process. The microstructure, chemical compositions and mechanical performances of the prepared ceramics were characterized. Experimental results showed that the phase compositions of the ceramics were highly dependent on the sintering temperate and time. 1 450 ℃ and 5 h could ensure almost all the SiO₂ to be transformed into SiC while lower temperature and longer or shorter time will remain or produce certain quantity of SiO₂ in the ceramics. The produced biological ceramic was actually a composite of higher proportional C and SiC, which was mainly formed and distributed on the surface of bamboo carbon. Compression strength, bending MOE and MOR of the composite ceramics were all found to increase and then decrease with the increase of SiO₂ weight gain. Optimal mechanical performances were achieved when SiO₂ weight gain was 10% and much more superior to those of bamboo carbon.

Key words: bamboo, sol-gel, SiC, biological ceramics