Effects of nitridation on properties of SiC fiber and interface of Ti matrix composite

The prenitridation of the TiBx coating surface of the Sigma SM1240 SiC fiber can form more stable compounds at the surface and obstruct the release of boron atoms into the Ti-based alloy matrix. The effect of nitridation on the tensile strength of the fiber was investigated in this work. Nitridation could degrade the tensile strength of the SiC fiber if the treating temperature and time were not optimized. The chemical reaction between the W core and SiC and the modification of the fiber microstructure during the nitridation are responsible for the degradation of the tensile strength. The strength can be maintained by the further optimization of the treating temperature and time. Therefore, stabilizing the surface of the TiBx coating and hence the interface of the SiCf/Ti composite by the nitridation of the SiC fiber is a feasible technique for practical applications. Ti-6Al-4V foil is used as the raw material of the matrix in the Ti-matrix composite.