Microstructural development of a Cf/ZrC composite manufactured by reactive melt infiltration

The microstructural development of a carbon fibre reinforced ZrC matrix composite, Cf/ZrC, manufactured by reactive melt infiltration (RMI) was investigated. The microstructural features of the composite were revealed by optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). It was found that the carbon fibre bundles are surrounded by continuous ZrC layers, while the composite matrix is composed of island-like ZrC particles dispersed within an α-Zr–ZrC eutectic phase. Nanosized inclusions were found inside some ZrC particles and it was demonstrated that they were α-Zr or α-Zr–ZrC. A formation mechanism of the unique matrix microstructure is proposed.