【摘要】 对碳化硅粉体在硫酸铝-硫酸钠复合熔盐反应转化成莫来石晶须的过程进行了研究。借助X射线粉末衍射仪(XRD)、红外光谱仪(IR)、高分辨透射电镜(TEM)、扫描电镜(SEM)和能谱仪(EDS),研究碳化硅与熔盐反应后的物相和微观形貌的变化。XRD和IR的结果表明,碳化硅在高温熔盐体系中可完全转化成莫来石晶须;SEM分析结果表明,莫来石沿[111]晶面优先生长形成晶须。并提出了循环的氧化-溶解机理,对碳化硅陶瓷粉体在复合熔盐中的反应过程进行了解释。更多还原

【Abstract】 The reactive process of silicon carbide in Al2(SO4)3-Na2SO4 molten salts system was studied.The surface morphology and phase transition were studied by X-ray diffraction(XRD),infrared spectroscopy(IR),transmission electron microscope(TEM),scanning electronic microscope(SEM),and energy dispersive spectrometer(EDS),respectively.XRD and IR results show that silicon carbide could be completely transform into mullite whiskers.TEM result showed that the mullite crystals grew along crystal plane firstly and developed into fibrous microstructure.An oxidation-dissolution mechanism was proposed for the explanation of the reaction of SiC powders in mixture molten salts.更多还原