Molten Salt Synthesis of Mullite Whiskers from Silicon Carbide Precursor

Mullite whiskers were prepared from SiC powders in molten Al2(SO4)3-Na2SO4 mixture salts at different temperatures. The morphology and phase composition of resulting whiskers were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) techniques. Mullite tiny fiber clusters with diameter about 50 nanometers and lengths of over several microns were obtained in 900°C mixture molten salts system. A new oxidation-dissolution mechanism was proposed for explanation mullite whiskers growth.