聚碳硅烷先驱体转化法制备SiC涂层研究

Studies on fabrication of silicon carbide coating from polycarbosilane precursor

以自合成的聚二甲基硅烷(PDMS)为原料,常压裂解合成聚碳硅烷(PCS),通过FT-IR分析PCS的结构,用GPC测定其分子量及分布,用熔点分析仪测定其熔点.在此基础上,采用聚碳硅烷先驱体转化法在石墨基体上制备SiC涂层,通过X射线衍射对涂层进行晶相分析,用扫描电镜分析涂层表面和横断面的形貌.结果表明,在石墨基体上形成了明显的β-SiC晶相,可以获得均匀、致密的SiC涂层,其厚度可通过涂层次数的改变进行调节,单次涂层最大厚度大约为2μm.

Using polydimethylsilane, Polycarbosilane precursor is synthesized by normal pressure pyrolysis. Its structure, molecule weight and features are characterized by FT -IR,GPC and other methods. Silicon carbide coating on graphite is fabricated from PCS precursor, The phase structure and composition of SiC coating are analysized by X - ray image; Its microscopic surface and cross - section morphology are investgated by scanning electron microscopes. The results show that Uniform and dense beta SiC coating is fabricated. The maximum thickness of coating obtaines 2μm through one process, but its thickness is increased by more times.