Manufacturing, analysis and modelling of porous Si-SiC ceramics derived by oxidation from C/C-Si-SiC composites

Abstract

Novel porous Si-SiC ceramics are derived by the oxidation of C/C-Si-SiC fibre matrix composites. The correlated mass loss and obtained open porosity depend on the temperature and holding times of the oxidation process. Microstructure and phase analyses of the Si-SiC composites are performed and supplemented with experimental determinations of the open porosity, the pore size distributionandsurface area. These macroscopic properties are influenced by the parameters of the oxidation process. Material parameters like the fibre alignment (weave style resp. fibre length) and phenolic resin type (resol and novolac) are considered as well. The experimental findings serve as a basis for modelling the open porosity. The open porosity and its pore size distribution are determined theoretically on this model basis and validated with the experimental results. © 2011 Göller Verlag.