化学液相气化沉积制备的炭/炭复合材料组织均匀性研究

采用化学液相气化沉积快速致密化工艺制备了C/C复合材料,分析了发热体尺寸和放置方式对材料组织均匀性的影响。通过排水法测量了材料轴向密度和孔隙率分布,采用偏光显微镜观察了材料的组织均匀性。结果表明,发热体尺寸越大,材料的组织均匀性增加,孔隙率降低,并能够缩短沉积时间;沉积过程中预制体内的温度分布是决定材料组织均匀性的主要因素。

Study on microstructure uniformity of carbon/carbon composites prepared by chemical liquid-vaporized infiltration

Carbon/carbon(C/C) composites were prepared by chemical liquid-vaporized infiltration(CLVI) method.The influences of size and position of graphite heater on microstructure uniformity of C/C composites were briefly analyzed.Density and porosity of C/C composites along axial direction were measured by penetration technique,and microstructure uniformity of the composites was observed by polarized light microscopy(PLM).The results show that microstructure uniformity is increased,porosity is decreased,and deposition time is reduced with the increase of graphite heater size.The temperature distribution inside the preforms plays an important role in microstructure uniformity of C/C composites.