Mullite-zirconia fibres produced by internal crystallization method: Microstructure and strength properties

Mullite-zirconia ceramics produced by powder metallurgy methods or directional solidification are well-known materials that combine the high creep resistance of mullite and the enhanced fracture toughness of a composite microstructure. These features provide a potential for the use of the material as a fibrous reinforcement for metal and ceramic matrices to obtain high-temperature fibrous composites. In this study, the microstructure and room- and high-temperature strength of mullite-ZrO2 fibres produced by the internal crystallisation method (ICM) were evaluated. The ICM provides a high productivity rate of fabrication technologies and, therefore, a potential to produce fibres suitable for structural applications. The room- and high-temperature strengths of the ICM fibres were comparable to those of the corresponding ceramics obtained by melt crystallization.