Solution based processing and properties of carbon fiber reinforced SiC+ZrO2 composites

Abstract Uni-directional carbon fiber (C f ) reinforced SiC + ZrO 2 composites were prepared by a solution approach in which the matrix was prepared using water-soluble precursors of colloidal silica, sucrose and zirconium oxychloride as sources of silica, carbon and zirconia respectively. After suitable heat treatment, the precursors convert into fine SiC + ZrO 2 particles with a uniform dispersion. In C f /SiC + ZrO 2 composites, in situ formation of SiC + ZrO 2 provides an effective way for uniform dispersion of SiC and ZrO 2 in the matrix. Analysis indicates complete reaction of the precursors to yield SiC + ZrO 2 as the composite matrix. The room temperature mechanical properties and the fracture behaviour of the composites were examined. A tensile strength of 617 ± 54 MPa and fracture energy of 2.69 ± 0.9 MJ/m 3 were obtained. The tensile strength of C f /SiC + ZrO 2 composites was twice that of C f /SiC composites produced by same approach. This is attributed to stabilization of the zirconia phase in the presence of the SiC phase by tailoring the starting materials and their composition.