The role of carbon biotemplate density in mechanical properties of biomorphic SiC

Biomorphic SiC was prepared from four types of Mediterranean wood as carbon precursor. Carbon biotemplates were obtained by pyrolysis and carbonization up to 1400 °C and they were infiltrated with liquid silicon in two different directions. A linear correlation between bending strength and bioSiC density for different types of softwood and hardwood has been found. Mechanical properties were modelled according to the MSA (minimum solid area) approach. Fairly good correlation was found when biomorphic SiC is treated as porous solid. Moreover, the fabrication of bioSiC from carbon biotemplates heat-treated up to 2500 °C has been additionally studied. An improvement up to 56% in flexural strength has been reached by densification of bioC at such high temperature.