碳化锆陶瓷先驱体裂解机理及PIP法制备C/C-ZrC复合材料(英文)

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

使用有机锆先驱体,通过先驱体高温裂解工艺制备C/C—ZrC复合材料。采用热重分析仪、傅里叶转换红外光谱、X射线衍射、扫描电子显微镜等手段研究该有机锆先驱体高温裂解过程中的热失重行为、官能团的转变情况、物相转化过程及显微组织。结果表明:有机锆先驱体从室温加热至1200℃时,首先生成无机态的二氧化锆,当裂解温度升高至1600℃时,二氧化锆通过碳热还原反应生成碳化锆陶瓷。对C/C—ZrC复合材料的显微组织观察表明,所制备的复合材料具有较好的结构特征:该复合材料的外表面形成一层碳化锆陶瓷层,复合材料内部的大部分孔隙由碳化锆陶瓷基填充。

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 ℃,then reduces to ZrC at 1600 ℃ 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.