Interfacial properties of SiCf/SiC minicomposites with a scheelite coating

Unidirectional SiCf/SiC minicomposite with a scheelite (CaWO4) interphase coating was fabricated through the precursor infiltration and pyrolysis method. Fractography of the SiCf/SiC minicomposites indicated that weak fiber/matrix bonding can be provided by the CaWO4 interphase. Furthermore, interfacial debonding stress of SiCf/CaWO4/SiC minicomposite was evaluated through the fiber push-out test, and estimated to be 80.7 +/- 4.6 MPa. In-situ tensile SEM observation of SiCf/CaWO4/SiC minicomposite after oxidation at 1000-1100 degrees C was carried out, and thermal compatibility between CaWO4 interphase coating and SiC fiber or matrix after heat treatment at 1300 degrees C was investigated.

Automated summary

A unidirectional SiCf/SiC minicomposite with a scheelite (CaWO4) interphase coating was fabricated through the precursor infiltration and pyrolysis method. The CaWO4 interphase was found to provide weak fiber/matrix bonding and the interfacial debonding stress was estimated. In-situ tensile SEM observation and investigation of thermal compatibility after heat treatment were conducted.