【摘要】 以炭布、环氧树脂和硅粉为原料,采用温压-原位反应法制备了炭纤维增强的碳化硅复合材料(2D C/C-SiC),考察了硅粉含量对材料结构和性能的影响。实验结果表明:随着硅粉含量的增加,材料的密度和石墨化度呈明显增加的趋势,材料的相对密度却逐渐减小,材料的弯曲强度呈现下降的趋势,但对剪切强度影响不大。在2100℃硅化处理后,材料的石墨化度由未添加硅时的21.7%增大为添加35%(质量分数,下同)时的45.2%,添加的硅与炭纤维和树脂炭反应后形成了SiC,沿炭纤维分布,材料中均不再含有自由的硅单质;当硅含量达到30%以上时,在纤维周围还有一些富碳的SiC颗粒存在。更多还原

【Abstract】 Carbon fiber reinforced silicon carbide composites were fabricated by warm compaction-in situ reaction process.The effects of Si content on the structure and properties of C/C-SiC were investigated.The results showed that with the increase of silicon,the density and the graphitization degree of the C/C-SiC composites gradually increased while the relative density was getting decreased and the flexural strength was lowered.But the shear strength had no obvious changes.After siliconizing at 2100℃,the graphitization degree of the C/C-SiC materials increased from 21.7% to 45.2% when silicon added up from zero to 35%(mass fraction).Silicon carbide was formed and distributed along the carbon fiber when Si reacted with carbon fiber and resin carbon.All Si was changed into SiC in the composite.When Si was over 30%(mass fraction),there were some carbon riched SiC particles around carbon fiber.更多还原