Linear expansion coefficient of the SiC/Si biomorphic composite

Abstract

In the temperature range 100–650 K, the linear expansion coefficient β was measured for the SiC/Si biomorphic composite, a new cellular ecoceramic fabricated from a porous cellular carbon matrix prepared through pyrolysis of wood (white eucalyptus) in an argon ambient with subsequent infiltration of molten Si into the channels of the matrix and the formation of 3C-SiC. The SiC/Si samples studied had an “excess” ∼30% volume concentration of Si and a porosity of ∼13–15%. The measurements were conducted on samples cut along (β∥) and across (β⊥) the tree growth direction. The measured values of β(T) of SiC/Si are compared with literature data available for the linear expansion coefficients of Si and 3C-SiC.