活性炭块诱发SiC晶须生长的研究

Research on Growth of SiC Whisker Induced by Active Carbon Block

以含氢硅油为前驱体,选用3种不同的活性炭块(1cm×1cm×1cm)为基体,经交联、制粉、包埋,氩气保护下烧结制备SiC晶须(SiCw)。对含氢硅油的交联工艺进行了研究,以正交试验法研究交联温度、保温时间、催化剂含量、交联剂含量对含氢硅油交联程度的影响。结果表明,交联温度是影响含氢硅油交联度的主要因素;其次依次是保温时间、催化剂含量、交联剂含量。在不同基体的诱导研究中,石墨基体表面生成的晶须较平直,另外两种基体未见均匀分布且长直的SiC晶须生成。SiC晶须的产生是由基体的表面缺陷引发,较低温度下晶须头部液滴的存在说明其生长机制符合VLS机制。

The SiC whiskers were obtained after cross-linking, milling, embedding, and sintering under an argon atmosphere, taking three different carbon blocks as substrates and low-cost hydrogen silicone oil（H-PSO） as raw material. The cross-linking process of hydrogen silicone oil was studied through orthogonal experiment, focusing on the effects of cross-linking temperature, holding time, catalyst content, and cross-linking agent ratio on the degree of cross-linking of hydrogen silicone oil. The results showed that temperature was the major factor followed by holding time, catalyst content and the cross-linking agent ratio. In the study of the induction by different substrates, the straight SiC whiskers were generated on the surface of graphite substrate, while no long-straight whiskers uniformly distributed on the other two substrates. The generation of SiC whiskers was induced by surface defect of the substrate. The presence of droplet on whiskers head at lower temperature demonstrated that the growth of SiC whiskers conformed to Vapor-Liquid-Solid mechanism.