Fabrication of size-controlled SiC/Si3N4 ceramic microspheres with enhanced extinction property

SiC/Si3N4 ceramic microspheres with good spherical structure were fabricated via a simple emulsion technique combined with the polymer-derived ceramics (PDCs) method. After pyrolyzed at 1400 °C, the SiC/Si3N4 ceramic microspheres exhibited controllable size distribution in the range of 0.60–0.66 µm and stable spherical morphology. The size and surface morphology of the ceramic microspheres were tuned by adjusting the operation conditions, such as O/W mass ratio, emulsifier amount, cross-linking time, cross-linking temperature and pyrolysis temperature. The effective specific extinction, e*, was used to evaluate the extinction performance of ceramic microspheres. e* of the ceramic microspheres pyrolyzed at 1400 °C reached maximum value, 40.7 m2/kg, and it indicated that the SiC/Si3N4 ceramic microspheres were promising high-temperature thermal insulating materials.