A novel polymer-derived high-temperature SiC/SiAlCN nanocrystalline glass ceramic

► Polymer alloy (CA) of polycarbosilane and polyaluminasilazane is used as precursor. ► Crystallization behavior of different domains in the CA is different. ► A novel SiC/SiAlCN microcrystal glass is prepared via pyrolysis of the CA at 1300 °C. ► Nano-crystalline SiC is uniformly dispersed in amorphous SiAlCN phase. ► Microstructure of the SiC/SiAlCN microcrystal glass can be kept up to 1500 °C.