C/C复合材料表面原位生长SiC_w的工艺

以三氯甲基硅烷(CH3SiCl3,MTS)为先驱体原料,采用化学气相沉积法在C/C复合材料基体上原位生长碳化硅晶须,研究稀释气体流量、催化剂以及沉积温度对碳化硅晶须生长的影响。结果表明:有催化剂存在时可以制备具有较高长径比的SiCw,无催化剂制备的SiC主要以短棒状或球状SiC为主;随着稀释气体流量或者沉积温度的增加,SiCw的产率是先增加、后减少,在1 100℃、载气和稀释气体流量均为100 mL/min时,制备的碳化硅晶须的产率最高,晶须质量最好。

Technology of in-situ growing SiC_w on surface of C/C composites

The silicon carbide whiskers were deposited on C/C composites by chemical vapor deposition(CVD) with methyltrichlorosilane(MTS) as the precursor.The effects of dilute gas flow,catalyst and deposition temperature on the growth of silicon carbide whiskers were investigated.The results show that silicon carbide whiskers(SiCw) with high length-diameter ratio are obtained when there is catalyst,but cosh-like or globular-like silicon carbides are got without catalyst,and with the increase of deposition temperature or the dilute gas flow,the yield of SiCw firstly increases and then decreases,and the highest yield and high quality of silicon carbide whiskers are obtained under the conditions as: deposition temperature of 1 100 ℃ and flow of carry gas and dilute gas both for 100 mL/min.