含铁碳化硅复合材料的制备

Preparation of Iron-containing Silicon Carbide Composites

以聚碳硅烷(PCS)、羰基铁(Fe(CO)_5)、二乙烯基苯(DVB)和碳化硅(SiC)纤维为原料,采用先驱浸渍裂解工艺制备含铁碳化硅纤维增强碳化硅基(SiC_f/SiC)复合材料,研究了原料配比对交联反应的影响,以及浸渍次数对复合材料致密度及陶瓷产率的影响。研究表明:当羰基铁添加量为20%(质量分数),二乙烯基苯为5%(质量分数)时有利于基体交联的进行;经1100℃裂解后基体中可明显观察到β-SiC晶体的生成;经5次浸渍裂解,制得的复合材料密度为1.72g/cm^3,孔隙率为20.43%,陶瓷产率得到提高,达到82.67%。

Silicon carbide(SiC) continuous fiber-reinforced silicon carbide composites were fabricated by precursor infiltration and pyrolysis process(PIP), in which composite liquid of divinylbenzene(DVB) and carbonyl iron(Fe(CO)5) with polycarbosilane(PCS) powder added was the infiltrate and SiC fibers were the reinforcement. The cross-linking properties of PCS was investigated by changing the mass ratios of Fe(CO)5 and DVB. The effect of the cycle of pyrolysis on the densification of the composites and ceramic yield were investigated. The results indicate that the pyrolysis product β-SiC is observable at 1100℃ in the matrix when the addition of carbonyl iron is 20 wt% and DVB is 5 wt%. After five infiltration-pyrolysis cycles ceramic yield of the SiC composites can reach 82.67% with the density of 1.72 g/cm3 and the porosity of 20.43%, Ceramic yield is relatively high.