The Oxidation of SiC Fiber and SiC Fiber Reinforced Boron Phenolic Resin Composite

Abstract

The SiC fiber was thermally treated in air atmosphere and the SiC fiber reinforced boron phenolic resin composite was prepared by hot molding process by introducing inorganic ceramic particles. The thermal stabilities, the surface microstructures, the diameter and oxygen mental content variations, and the crystal structures of SiC fiber heated and kept for 0.5 h and 1h at different high temperatures were investigated through TG, SEM, XRD analysis. The cross-section morphology of the composite also observed. The results showed that the SiC fiber had good thermal resistance at high temperature in N2, however it was easy to be oxidized at high temperature in air. When heated from 25 °C to 1600 °C and kept for 1 h, the fiber was oxidized to SiO2 and the fiber surface was coarse and cracked. With the temperature increasing, the diameter of the fiber decreased and the oxygen content increased. Highly different form the cross-section morphology of SiC fiber itself heated in air, the cross-section morphology of SiC fiber in composite was weakly oxidized and the cross section was smooth and there was no distinct oxidation layer existing.