The effect of transition metals oil the morphology and the yield of β-SiC whiskers has been investigated by vapor phase reaction in SiCl₄-Cl₂C = CH₂-H₂ system. The β-SiC whiskers formed on graphite substrate are mainly of straight shape with blunted tip at their top. Depending on the transition metals added, β-SiC whiskers are in various shapes such as straight, needle-like, gnarled, concentric double-layered, or hollow. The length and the yield of H-SiC whiskers increased by metal addition in the order of Ni$lt;Co$lt;Fe. The solubility of carbon in the metal-Si-C alloy droplet at the tip of the whiskers is associated with the length and the yield of the whiskers. |
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