Pyrolysis mechanism of ZrC precursor and fabrication of C/C-ZrC composites by precursor infiltration and pyrolysis

C/C-ZrC composites were prepared by precursor infiltration and pyrolysis using the organic zirconium as precursor. The conversion mechanisms of the precursors such as the thermal behavior, structural evolution, phase composition, microstructure, composition of the precursors and products were analyzed by thermal gravimetric analyzer, Fourier transform infrared spectrometer, X-ray diffraction and scanning electron microscope. The results indicate that the ZrC precursor transforms to inorganic ZrO₂ from room temperature to 1200 °C, then reduces to ZrC at 1600 °C through the carbothermal reduction reaction. The microstructure of the C/C-ZrC composites was also investigated. The composites exhibit an interesting structure, a coating composed of ZrC ceramic covers the exterior of the composite, and the ZrC ceramic is embedded in the pores of the matrix inside the composite.