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

摘要

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 degrees C, the SiC/Si3N4 ceramic microspheres exhibited controllable size distribution in the range of 0.60-0.66 mu m 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 degrees C reached maximum value, 40.7 m(2)/kg, and it indicated that the SiC/Si3N4 ceramic microspheres were promising high-temperature thermal insulating materials. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.