用化学气相反应法在石墨基体上制备SiC涂层

  • 摘要: 石墨是建造高温气冷堆的主要材料,提高其抗氧化性能可以进一步改善高温气冷堆安全性。本文对利用化学气相反应法(CVR)在高温气冷堆燃料元件基体石墨上制备SiC涂层的工艺进行了探讨,利用XRD、Raman谱及SEM对制备的SiC涂层进行了分析。结果表明,可以获得单一βSiC相的SiC涂层,涂层与基体之间具有良好的梯度过渡;但由于在涂层中存在一定的孔隙,仅用CVR制备的SiC涂层不能很好地改善石墨的抗氧化性能,将此方法和其他方法结合起来可以获得低成本的、均匀的SiC抗氧化涂层。

     

    Abstract: The improvement of the oxidation resistance of graphite, which is the key materials for construction of high temperature gas-cooled reactor(HTR), can further improve the safety of HTR. SiC coatings were fabricated by chemical vapor reaction (CVR) on HTR fuel element matrix graphite, and the structure characteristics of SiC coatings were analyzed with XRD, Raman spectra and SEM. The coatings with only β-SiC was obtained and the ideal gradual transition layers existed at the interface between the coatings and substrates. There existed some small pore in SiC coatings fabricated by CVR, which made the coatings only by CVR obtaining poor oxidation resistance; but uniform SiC coatings with excellent oxidation resistance at low cost could be obtained by combining CVR and other fabrication methods.

     

/

返回文章
返回