Vapor-solid process, silicon carbide whiskers

A vapor-liquid-solid (VLS) technique (Petrovic et al, 1985 Milewski et al, 1985) can be used to grow exceptionally strong and stiff silicon carbide whiskers. The name VLS comes from the fact that the process uses vapor feed gases, a liquid catalyst, and solid crystalline whiskers are the end product. Figure... 

The formation of silicon carbide whiskers can occur through one of three general methods vapor-solid (VS), chemical vapor deposition (CVD), vapor-liquid-solid (VLS). The processes vary widely in the raw... 

Silicon carbide whiskers, usually produced from silica and carbon, are widely used for ceramic matrix composites [38]. Tbe vapor-liquid-solid (VLS) process is accepted as the mechanism for SiC whisker production (Fig. 15.1.4). This process requires formation of a liquid phase of a transition metal at the reaction sites. Elemental sources of Si and C are usually supplied in vapor phase form as SiO and CH4, respectively [39]. The vapors are deposited on the surface of the liquid metal and dissolved into the liquid metal droplets. Since the whiskers are precipitated from the dissolved components, metal droplets are often observed at the tip of the whiskers [39]. 

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